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Trane LO - page 1
Installation Operation Maintenance UniT rane ® Fan-Coil Room Conditioners Force Flo™ Cabinet Heaters Sizes 02-12 Low V ertical Fan-Coils Sizes 03-06 UNT -IOM-6 Supercedes UNT -IOM-5 April 2000 Models “LO” Design Sequence and Later ...
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Trane LO - page 2
2 UNT -IOM-6 T able of Contents General Information3 Cabinet Styles4 Model Number Description6 Receiving and Handling9 Jobsite Storage10 Installation Considerations1 1 Service Access12 Installation Checklist13 V ertical Units15 Installing the Unit15 Horizontal Units16 External Insulating Require- ments20 Startup ...
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Trane LO - page 3
UNT -IOM-6 3 UniTrane ® fan-coil and Force Flo cabinet heaters units are single room units with load capabilities of 200 to 1200 cfm. See Figure 1 for unit components. Fan-coil units are available as 2-pipe with or without electric heat (one hydronic circuit) or 4-pipe (two hydronic circuits). Force Flo units feature 2-pipe hydronic coils, e ...
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Trane LO - page 4
4 UNT -IOM-6 Model F Wall Hung Cabinet** Model B V ertical Cabinet Model A V ertical Concealed Cabinet Styles Model C Horizontal Concealed Model D Horizontal Cabinet Model E Horizontal Recessed ...
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Trane LO - page 5
UNT -IOM-6 5 Model K Low V ertical Concealed* Model L Low V ertical Cabinet* Model M Inverted V ertical Cabinet** Model N Inverted V ertical Recessed** *Fan-coil only **Force Flo cabinet heater only Model J V ertical Slope T op Cabinet Model H V ertical Recessed ...
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Trane LO - page 6
6 UNT -IOM-6 Figure 2. The unit nameplate is on the fan scroll. Model Number Description Each UniTrane ® fan-coil and Force Flo cabinet heater has a multiple character model number unique to that particular unit. T o determine a units specific options, reference the model number on the unit nameplate on the fan scroll. The unit nameplate al ...
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Trane LO - page 7
UNT -IOM-6 7 Model Number Description J With piping, RH K With piping, LH L With piping, RH, ext. end pocket M With piping, RH, ext. end pocket Digits 10 & 11 Design Sequence LO Digit 12 Inlet A Front toe space B Front bar grille C Front stamped louver D Bottom stamped louver E Bottom toe space F Back duct collar G Open return H Back stamped lo ...
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Trane LO - page 8
8 UNT -IOM-6 R 7 falseback T 8 falseback Digit 40 Main Auto Circuit Setter GPM 0 None A 0 . 5 B 0.75 C 1 . 0 D 1 . 5 E 2 . 0 F 2 . 5 G 3 . 0 H 3 . 5 J 4 . 0 Digit 41 Auxiliary Auto Circuit Setter GPM 0 None A 0 . 5 B 0.75 C 1 . 0 D 1 . 5 E 2 . 0 F 2 . 5 G 3 . 0 H 3 . 5 J 4 . 0 Digit 42 Subbase 0 None A 2 height B 3 height C 4 height ...
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Trane LO - page 9
UNT -IOM-6 9 Receiving and Handling UniTrane ® fan-coil and Force Flo cabinet heaters ship in individual cartons for maximum protection during shipment and for handling and storage ease. Each carton has tagging information such as the model number , sales order number , serial number , unit size, piping connections, and unit style to help prope ...
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Trane LO - page 10
10 UNT -IOM-6 This unit is intended for indoor use only . T o protect the unit from damage due to the elements and prevent it from possibly becoming a contaminant source for IAQ problems, store the unit indoors. If indoor storage is not possible, the Trane Company makes the following provisions for outdoor storage: 1. Place the unit(s) on a dry sur ...
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Trane LO - page 11
UNT -IOM-6 11 Complete the following checklist before installing the unit. o 1. Clearances Allow adequate space for free air circulation, service clearances, piping and electrical connections, and any necessary ductwork. For specific unit dimensions, refer to the submittals. Allow clearances according to local and national electric codes. See the f ...
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Trane LO - page 12
12 UNT -IOM-6 Service access is available from the front on vertical units and from the bottom on horizontal units. Cabinet and recessed units have removable front or bottom panels to allow access into the unit. See Figure 3 for recommended service and operating clearances. Units have either right or left hand piping. Reference piping locations by ...
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Trane LO - page 13
UNT -IOM-6 13 The following checklist is only an abbreviated guide to the detailed installation procedures given in this manual. Use this list to ensure all necessary procedures are complete. For more detailed information, refer to the appropriate sections in this manual. WARNING: Allow rotating fan to stop before servicing equipment. Failure to do ...
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Trane LO - page 14
14 UNT -IOM-6 o 9. Complete condensate drain line connections on fan-coil units. o 10. Install automatic changeover sensor option on the supply water line. o 11 . Install automatic electric heat lockout switch option on the supply water line. o 12. Install condensate overflow switch option correctly on the auxiliary drain pan. o 13. Install the low ...
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Trane LO - page 15
UNT -IOM-6 15 Size L (in.) 02 21 1/4 03 21 1/4 04 26 1/4 06 35 3/4 08 44 1/4 10 63 1/4 12 63 1/4 Floor Level 15.5 in. 7.5 in. L L 12.19 in. Floor Level V ertical Units Figure 4. Keyslot Hanger Hole Locations Installing the Unit Before beginning installation, refer to T able 1 on page 17 for unit weights and Figure 3 on page 12 for service and opera ...
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Trane LO - page 16
16 UNT -IOM-6 4. Insert the threaded rods or lag screws in the wall before setting the unit in place. 5. Remove the front panel (cabinet unit only) by lifting it upward. 6. Position the hanger holes, located on the back of the unit, over the rod or lag screw heads, pushing the unit downward to properly position. 7. Complete piping and wiring connec ...
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Trane LO - page 17
UNT -IOM-6 17 2. Position and install the suspension rods or a suspension device (supplied by installer) according to the unit size dimensions in Figure 4 on page 15. Also refer to the weight range chart given in T a ble 1. 3 . On cabinet units, remove the bottom panel by using a 5/32 inch Al l e n wrench to unscrew fasteners. Swing the panel down ...
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Trane LO - page 18
18 UNT -IOM-6 Cabinet units: Install the bottom panel by placing the hinged end on the units hinged end (always at the return end of the unit). See Figure 4 on page 15 for keyslot hanger hole locations. Swing the panel upward into position. Tighten the panel to the unit with the fasteners provided. Do not over- tighten the fasteners. Recessed un ...
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Trane LO - page 19
UNT -IOM-6 19 Figure 5. T rim ring assembly installation. ...
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Trane LO - page 20
20 UNT -IOM-6 o 1. Ensure all panels are in place. o 2 . Tighten unions adequately if unit has a factory deluxe piping package. o 3. Properly vent the hydronic coil to allow water flow through the unit. o 4. Set water flow to the unit properly if unit piping has the circuit setter valve. o 5. Check strainers (if supplied) for debris after applying ...
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Trane LO - page 21
UNT -IOM-6 21 Before installing field piping to the coil, consider the following . · All coil connections are 5/8 inch O.D. (or 1/2 inch nominal) female copper connections. · The supply and return piping should not interfere with the auxiliary drain pan or condensate line. See Connecting the Condensate Drain section on page 25 for more deta ...
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Trane LO - page 22
22 UNT -IOM-6 Note: For vertical fan-coil units, push the main condensate drain hose and overflow condensate drain hose through to the inside of the chassis end panel to prevent them from being burned when making sweat connections. Be sure to pull the hoses back through and route to the auxiliary drain pan when the end panel has cooled. 3. Solder t ...
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Trane LO - page 23
UNT -IOM-6 23 4. V ent the vacuum breaker line to atmosphere or connect it into the return main at the discharge side of the steam trap. 5. Pitch all steam supply and return mains down a minimum of 1 inch per 10 feet in the direction of flow . 6. Do not drain the steam mains or take-off through the coils. Drain the mains ahead of the coils through ...
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Trane LO - page 24
24 UNT -IOM-6 Before installing water piping supply and return lines to factory piping package, note the following items. · All piping connections are 5/8 inch O.D. (1/2 inch nominal) female copper connections. · The fan-coil supply and return piping should not interfere with the auxiliary drain pan or condensate line. See Connecting the Conde ...
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Trane LO - page 25
UNT -IOM-6 25 Connecting the Condensate Drain The auxiliary drain pan ships loose with a fan-coil unit with factory piping. T o install the auxiliary drain pan, insert the t abs, located on the side of the drain pan, into the slots located in the chassis end panel. Slide the pan into the narrow groove section to lock into place. See Figures 10 and ...
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Trane LO - page 26
26 UNT -IOM-6 inch inside diameter flexible plastic tube over the nipple and secure with a field supplied hose clamp. Note: The installer is responsible for adequately insulating field piping. See the External Insulating Requirements section on page 20 for more information. The condensate overflow detection device is an option on fan-coil units ...
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Trane LO - page 27
UNT -IOM-6 27 When using field supplied 3-way valves, position the changeover sensor upstream of the valve on the supply water pipe. Recommendation: When using field supplied 2-way control valves, attach the changeover sensor in a location that will detect an active water temperature. The unit must always be able to sense the correct system water t ...
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Trane LO - page 28
28 UNT -IOM-6 The hydronic coil contains a vent, either manual or automatic, to release air from the unit. This vent is not sufficient for venting the water piping system in the building. Locate the coil air vent on the piping side, above the coil connections on the unit. Perform the following steps to vent the coil after installing the unit. See F ...
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Trane LO - page 29
UNT -IOM-6 29 The manual circuit setter valve is an optional end valve supplied on the return pipe of the factory piping package. The valve allows the operator to regulate water flow through the hydronic coil, balance the water flow through the unit with other units in the piping system, and serves as a shutoff or end valve. See Figure 17. Follow t ...
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Trane LO - page 30
30 UNT -IOM-6 securely set the open memory position. The memory stop indicates the last set open position. 7. If using a 3-way valve: close the control valve to the coil, with the differential pressure meter still connected. This will divert flow to the bypass side of a 3-way valve. Adjust the balancing fitting to obtain the same pressure drop acro ...
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Trane LO - page 31
UNT -IOM-6 31 The automatic flow valve is an optional end valve on the return of the factory piping package. See Figure 20. The valve regu- lates water flow through the coil to a specific (gpm) flow rate, as ordered by the customer . The automatic flow valve controls to the specified flow rate, pro- vided that the pressure drop across the valve is ...
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Trane LO - page 32
32 UNT -IOM-6 The units airflow configuration varies dependent on the model and options ordered. A one-inch duct collar is provided on units with a ducted return and/or discharge to attach ductwork to the unit. The Trane Company recommends using galvanized sheet metal ductwork with fan-coil and cabinet heater units. Slide the sheetmetal duct ove ...
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Trane LO - page 33
UNT -IOM-6 33 Electrical Connections Supply Power Wiring Refer to the unit nameplate to obtain the minimum circuit ampacity (MCA) and maximum fuse size (MFS) or maximum circuit breaker (MCB) to properly size field supply wiring and fuses or circuit break- ers. See Figure 2 on page 6 to reference the nameplate location. Refer to the unit operating v ...
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Trane LO - page 34
34 UNT -IOM-6 Figure 23. The terminal unit control (TUC) board pivots downward to provide service access. ! All field wiring should conform to NEC and all applicable state and local code require- ments. The control panel box is always on the end opposite the piping connections. Access the control box by removing the two screws that secure the front ...
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Trane LO - page 35
UNT -IOM-6 35 T able 3. Maximum Wiring Distances, ft (m) Device Wire Size Range Max. Wiring Distance Fan Mode Switch 14 - 2 2 A WG 500 (152.4) Zone Sensor Module 16 - 22 AWG 200 (60.96) All sensor and input circuits are normally at or near ground (common) potential. When wiring sensors and other input devices to the Tracer ® ZN.010, ZN.510, ZN.520 ...
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Trane LO - page 36
36 UNT -IOM-6 Installing Wall Mounted Controls Wall mounted controls, which include the fan mode switch and the zone sensor module, ship loose inside the unit accessory bag. Position the controller on an inside wall 3 to 5 feet above the floor and and at least 18 inches from the nearest outside wall. Installing the controller at a lower height may ...
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Trane LO - page 37
UNT -IOM-6 37 Follow the procedure below to install the zone sensor module. Reference Figure 25 on page 38 when installing the wall mounted zone sensor . 1. Note the position of the setpoint adjustment knob and gently pry the adjustment knob from the cover using the blade of a small screwdriver . 2. Insert the screwdriver blade behind the cover at ...
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Trane LO - page 38
38 UNT -IOM-6 Figure 26. Resistance temperature curve for the zone sensor , entering water temperature sensor , and discharge air sensor . Wall mounted zone sensor Model # Digit 31 = W Split-mounted option: Wall mounted setpoint dial with unit mounted fan mode switch Model # Digit 31 = X Figure 25. Wall mounted zone sensor dimensions. ...
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Trane LO - page 39
UNT -IOM-6 39 Fan Mode Switch Manual Fan Mode Switch The manual fan mode switch is available for fan-coil units that do not have Trane factory-mounted control packages. This four-position switch (off-hi-med-lo) allows manual fan mode selection and is available unit or wall mounted. The unit-mounted option (Digit 31 = D) operates on line voltage. Th ...
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Trane LO - page 40
T racer ® ZN.010 and ZN.510 40 UNT -IOM-6 T racer ® ZN.010 and ZN.510 The Tracer ® ZN.010 is a stand-alone device that controls fan-coils and cabinet heaters. The Tracer ® ZN.510 can be stand-alone or utilize peer-to-peer commu- nications. The controller is easily accessible in the control end panel for service. The control end panel is on the ...
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Trane LO - page 41
UNT -IOM-6 41 T racer ® ZN.010 and ZN.510 Operating Information Power -Up Sequence Entering Water T emperature Sampling Function When 24 V AC power is initially applied to the T racer ® ZN.010 or ZN.510, the following sequence occurs: 1. All outputs are controlled off. 2. Tracer ® ZN.010 and ZN.510 reads all input values to detemine initial valu ...
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Trane LO - page 42
T racer ® ZN.010 and ZN.510 42 UNT -IOM-6 BIP3: Occupancy Sensor Binary input #3 (BIP3) on Tracer ® ZN.010 and ZN.510 is available for field- wiring an occupancy sensor , such as a binary switch or a timeclock, to detect occupancy . The sensor can be either normally open or normally closed. Reference T able 5 on page 43. The factory hard wires th ...
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Trane LO - page 43
UNT -IOM-6 43 T racer ® ZN.010 and ZN.510 T able 6. Binary Outputs Binary Output D escription Pi n BOP1 Fan high speed J1-1 BOP2 Fan medium speed J1-2 BOP3 Fan low speed J1-4 BOP4 Main valve J1-5 BOP5 Auxiliary valve/electric heat J1-6 BOP6 2-position fresh air damper J1-7 Notes: 1. In a four-pipe application, BOP4 is used for cooling and BOP5 is ...
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Trane LO - page 44
T racer ® ZN.010 and ZN.510 44 UNT -IOM-6 The zone sensors available with the Tracer ® ZN.010 and ZN.510 provide up to three different inputs 1. Space temperature measurement (10K thermistor) 2. Local setpoint 3. Fan mode switch Wall mounted zone sensors include a thermistor as a component of the internal printed circuit board. Unit mounted zone ...
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Trane LO - page 45
UNT -IOM-6 45 T racer ® ZN.010 and ZN.510 T able 9. V alid Operating Range and Factory Default Setpoints Setpoint/Parameter D efault Setting V alid Operating Range Unoccupied cooling setpoint 85 ° F 40 to 1 15 ° F Occupied cooling setpoint 74 ° F 40 to 1 15 ° F Occupied Heating setpoint 71 ° F 40 to 1 15 ° F Unoccupied heating setpoint 60 ° ...
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Trane LO - page 46
T racer ® ZN.010 and ZN.510 46 UNT -IOM-6 T roubleshooting Figure 28. The T racer ZN.010 board. T able 10. Red Service LED Activity Red LED Blink Activity LED off continuously when power is applied to the controller LED on continuously , even when power is applied to the controller LED flashes once every second LED Activity Red SERVICE LED Red Ser ...
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Trane LO - page 47
UNT -IOM-6 47 T racer ® ZN.010 and ZN.510 T able 12. Y ellow COMM LED Activity Y ellow LED Blink Activity Description LED off continuously The controller is not detecting any communication. (Normal for units in standalone applications) LED blinks The controller detects communication. LED on continuously Abnormal condition T able 1 1. Green ST A TU ...
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Trane LO - page 48
T racer ® ZN.010 and ZN.510 48 UNT -IOM-6 The outputs are not subject to minimum times during the test se- quence. However, the test sequence only permits one step per second which limits minimum output time. The green LED is turned off when the T est button is pressed. T o begin the manual output test mode, press and hold the T est button (turnin ...
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Trane LO - page 49
UNT -IOM-6 49 T racer ® ZN.010 and ZN.510 T able 13. T est Sequence for 1-Heat /1-Cool Configurations St ep s F an Cool Output Heat Output Damper BOP1-3 BOP4 (1) BOP5 BOP6 1. Of f O ff O ff O ff Closed 2. Fan High High O ff O ff C losed 3. Fan Medium Medium Off Of f C losed 4. Fa n Low L ow O ff Off C losed 5. Cool Hi gh On Off C losed 6. Heat H i ...
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Trane LO - page 50
T racer ® ZN.010 and ZN.510 50 UNT -IOM-6 Notes: Priority Level: Diagnostics are listed in order from highest to lowest priority . The controller senses and records each diagnostic independently of other diagnostics. It is possible to have multiple diagnostics present simultaneously . The diagnostics affect unit operation according to priority lev ...
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Trane LO - page 51
UNT -IOM-6 51 T racer ® ZN.010 and ZN.510 Cycling Power to the Controller There are four ways in which diagnostics are reset: 1. Automatic reset by the controller 2. By initiating a manual output test at the controller 3. By cycling power to the controller 4. Through Rover, Tranes service tool The controller includes an automatic diagnostic ...
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Trane LO - page 52
T racer ® ZN.010 and ZN.510 52 UNT -IOM-6 T rane’ s Service T ool, Rover™ Alarm Reset Rover, Tranes service tool, can reset diagnostics present in the controller . For complete information about Rover, refer to Trane publication EMTX-IOP-2 Rover Installation, Operation and Program- ming Guide . Any device that can communicate alarm re ...
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Trane LO - page 53
UNT -IOM-6 53 T racer ® ZN.010 and ZN.510 T able 15. Fan Outputs do not Energize Probable Cause Explanation Random start After power-up, the controller always observes a random start that varies observed between 0 and 25 seconds. The controller remains off until the random start time expires. Power-up control wait When power-up control wait is ena ...
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Trane LO - page 54
T racer ® ZN.010 and ZN.510 54 UNT -IOM-6 T able 16. V alves St ay Closed Probable Cause Explanation Normal operation The controller opens and closes the valves to meet the unit capacity require- ments. Requested mode: off It is possible to communicate the operating mode (such as off, heat, and cool) to the controller . When of f is communicated t ...
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Trane LO - page 55
UNT -IOM-6 55 T racer ® ZN.010 and ZN.510 T able 17. V alves St ay Open Probable Cause Explanation Normal operation The controller opens and closes the valves to meet the unit capacity require- ments. V alve override The controller can communicate a valve override request to affect the valve operation. Manual output test The controller includes a ...
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Trane LO - page 56
T racer ® ZN.010 and ZN.510 56 UNT -IOM-6 T able 18. Electric Heat Not Operating Probable Cause Explanation Normal operation The controller cycles electric heat on and off to meet the unit capacity require- ments. Requested mode: off It is possible to communicate the operating mode (such as off, heat, cool) to the controller . When off is communic ...
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Trane LO - page 57
UNT -IOM-6 57 T racer ® ZN.010 and ZN.510 T able 19. Fresh Air Damper St ays Closed Probable Cause Explanation Normal operation The controller opens and closes the fresh air damper based on the controllers occupancy mode and fan status. Normally , the fresh air damper is open during occupied mode when the fan is running and closed during unoccu ...
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Trane LO - page 58
T racer ® ZN.010 and ZN.510 58 UNT -IOM-6 T able 20. Fresh Air Damper Stays Open Probable Cause Explanation Normal Operation The controller opens and closes the fresh air damper based on the controllers occupancy mode and fan status. Normally , the fresh air damper is open during occupied mode when the fan is running and closed during unoccupie ...
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Trane LO - page 59
UNT -IOM-6 59 T racer ® ZN.520 Tracer ® ZN.520 is a communicating or standalone device. It is easily accessible in the control end panel for service. The control end panel is on the end opposite the piping. Sequence of Operations OFF: Fan is off; control valve options and fresh air damper options close. The low air temperature detection option is ...
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Trane LO - page 60
T racer ® ZN.520 60 UNT -IOM-6 Follow these general guidelines when installing communication wiring: 1 ) Maintain a maximum 5000 ft. aggregate run 2 ) Install all communication wiring in accordance with the NEC and all local codes. 3 ) Solder the conductors and insulate (tape) the joint sufficiently when splicing communication wire. Do not use wir ...
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Trane LO - page 61
UNT -IOM-6 61 T racer ® ZN.520 T racer ® ZN.520 Unit Start-Up Refer to the Trane publication, CNT-IOP-2 Installation Operation and Programming Guide , to operate the Tracer ® ZN.520 with Trane Integrated Comfort System (ICS). The factory pre-programs the Tracer ® ZN.520 with default values to control the temperature and unit airflow . Use Tr ...
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Trane LO - page 62
T racer ® ZN.520 62 UNT -IOM-6 When the controller is in the occupied mode, the unit attempts to maintain the space temperature at the active occupied heating or cooling setpoint, based on the measured space temperature, the discharge air temperature, the active setpoint, and the proportional/ integral control algorithm. The modulating control alg ...
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Trane LO - page 63
UNT -IOM-6 63 T racer ® ZN.520 standby cooling and heating setpoints. Because the occupied standby setpoints typically cover a wider range than the occupied setpoints, the Tracer ® ZN.520 controller reduces the demand for heating and cooling the space. Also, the outdoor air economizer damper uses the economizer standby minimum position to reduce ...
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Trane LO - page 64
T racer ® ZN.520 64 UNT -IOM-6 refer to the product-specific literature from that manufacturer . If the unit is communicating with Tracer Summit and the supply fan control programming point is configured for Tracer (the factory config- ures as local), then Tracer Summit will control the fan regardless of the fan mode switch position. All Tracer ® ...
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Trane LO - page 65
UNT -IOM-6 65 T racer ® ZN.520 The Tracer ® ZN.520 controller operates the supply fan continuously when the controller is in the occupied and occupied standby modes, for either heating or cooling. The controller only cycles the fan off with heating and cooling capacity in the unoccupied mode. The economizer is used for cooling purposes whenever t ...
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Trane LO - page 66
T racer ® ZN.520 66 UNT -IOM-6 Unit diagnostics can affect the Tracer ® ZN.520 controller operation, causing unit operation to be defined as abnormal. Refer to the Troubleshooting section for more information about abnormal unit operation. The heating output is controlled based on the heating capacity . At 0% capacity , the heating output is of f ...
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Trane LO - page 67
UNT -IOM-6 67 T racer ® ZN.520 switch depending on the error . Fan speed increases as the space temperature rises above the active cooling setpoint. T able 21. Fan Configuration Auto fan operation Fan speed default Heating Continuous O f f Low Medium High CoolingContinuous O f f Low Medium High Additional flexibility built into the controller allo ...
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Trane LO - page 68
T racer ® ZN.520 68 UNT -IOM-6 Hea tin g Cooling Fan mode Occ. Unocc. Occ. Unocc. O f f Of f Off Off O ff L o w Low Off/High Low O ff/High Medium Me d Off/High M ed O ff/High High Hi gh O ff/High Hig h O ff/High Auto (continuous) Default Off/High Default Off/High fan sp. fan sp. During occupied and occupied standby modes, the fan normally is on. F ...
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Trane LO - page 69
UNT -IOM-6 69 T racer ® ZN.520 On a transition from off to any other fan speed, the Tracer ® ZN.520 controller automatically starts the fan on high speed and runs the fan at high speed for 0.5 seconds. This provides the ample torque required to start all fan motors from the off position. Tracer ® ZN.520 can sample the entering water temperature ...
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Trane LO - page 70
T racer ® ZN.520 70 UNT -IOM-6 warm enough to heat when it is five degrees above the measured space temperature. When the controller invokes the entering water temperature sampling function, the unit opens the main hydronic valve for no more than three minutes before considering the measured entering water temperature. An initial stabilization per ...
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Trane LO - page 71
UNT -IOM-6 71 T racer ® ZN.520 to expose the damper stop screw on the control panel end. Relocate the stop screw to the appropriate position. Then loosen the stop screw wingnut and adjust the linkage. Economizer Damper With a valid outdoor air temperature (either hardwired or communi- cated), Tracer ® ZN.520 uses the modulating economizer damper ...
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Trane LO - page 72
T racer ® ZN.520 72 UNT -IOM-6 Dehumidification is possible when mechanical cooling is available, the heating capacity is located in the reheat position, and the space relative humidity setpoint is valid.The controller starts dehumidifying the space when the space humidity exceeds the humidity setpoint. The controller continues to dehumidify until ...
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Trane LO - page 73
UNT -IOM-6 73 T racer ® ZN.520 input as not used. BIP Description F an V alve Electric heat D am pe r BI 1 Low temperature detection O f f Open O ff C losed BI 2 Condensate overflow O ff Closed O f f Closed BI 4 Fan status Of f Cl osed Off Cl osed T able 26. Binary Input Configurations B in ar y Controller operation Input Description Configuration ...
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Trane LO - page 74
T racer ® ZN.520 74 UNT -IOM-6 Binary outputs are configured to support the following: Three fan stages (when one or two fan stages are present, medium fan speed can be configured as exhaust fan) One hydronic cooling stage One hydronic heating stage (dehumidification requires this to be in the reheat position) One DX cooling stage ...
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Trane LO - page 75
UNT -IOM-6 75 T racer ® ZN.520 T able 28. Analog Inputs Description T erminals Function Range Zone TB 3- 1 Space temperature input 5° to 122°F (-15° to 50°C) Ground TB3-2 Analog ground NA Set T B 3 - 3 Setpoint input 40° to 1 15°F (4.4° to 46.1°C) F an T B 3 - 4 Fan switch input 4821 to 4919 W (Off) 2297 to 2342 W (Auto) 10593 to 10807 W ( ...
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Trane LO - page 76
T racer ® ZN.520 76 UNT -IOM-6 The Tracer ® ZN.520 controller accepts the following zone sensor module inputs: S pace temperature measurement (10kW thermistor) Local setpoint (either internal or external on the zone sensor module) Fan switch Timed override (On) and Cancel timed override Communication jack Trane zone sensors us ...
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Trane LO - page 77
UNT -IOM-6 77 T racer ® ZN.520 These setpoint limits only apply to the occupied and occupied standby heating and cooling setpoints. These setpoint limits do not apply to the unoccupied heating and cooling setpoints stored in the controllers configuration. When the controller is in unoccupied mode, it always uses the stored unoccupied heating an ...
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Trane LO - page 78
T racer ® ZN.520 78 UNT -IOM-6 T able 29. Zone sensor wiring connections T B1 Description 1 Space temperature 2 Common 3 Setpoint 4 Fan mode 5 Communications 6 Communications The Tracer ® ZN.520 controller communicates via Tranes Comm5 protocol. T ypically , a communication link is applied between unit controllers and a building automation sys ...
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Trane LO - page 79
UNT -IOM-6 79 T racer ® ZN.520 T able 30. T racer ® ZN.520 Diagnostics Diagnostic F a n Other Outputs (Note 1) Condensate overflow O f f V alves Closed, Fresh air damper Closed, electric heat Off, Baseboard heat Off Low temperature detection O f f V alves Open, Fresh air damper Closed, electric heat Off, Baseboard heat Off Low air flow - fan fail ...
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Trane LO - page 80
T racer ® ZN.520 80 UNT -IOM-6 Note 3: When the outdoor air temperature sensor has failed or is not present, the T racer ® ZN.520 controller generates a diagnostic to indicate the sensor loss condition. The controller automatically clears the diagnostic once a valid outdoor air temperature value is present (non-latching diagnostic). When the outd ...
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Trane LO - page 81
UNT -IOM-6 81 T racer ® ZN.520 If a Low T emperature Detection diagnostic recurs within 24 hours after an automatic diagnostic reset, you must manually reset the diagnos- tic. See other possible methods for resetting diagnostics in this section. Manual output test: Y ou can use the T est button on the controller either during installation to verif ...
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Trane LO - page 82
T racer ® ZN.520 82 UNT -IOM-6 LED Operation Red Service LED T able 31. Red Service LED Activity LED Activity Description Off continuously after Normal operation power is applied to the controller . On continuously , even when Someone is pressing the Service power is first applied to the button or the controller has failed. controller . LED flashe ...
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Trane LO - page 83
UNT -IOM-6 83 T racer ® ZN.520 T able 32. Green St atus LED activity Green LED activity D escription On continuously Power on (normal operation) Blinks (one blink) The controller is in manual output test mode. No diagnostics present. Blinks (2 blinks) The controller is in manual output test mode. One or more diagnostics are present. LED blinks (1/ ...
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Trane LO - page 84
T racer ® ZN.520 84 UNT -IOM-6 LED Operation The green status LED is off when you press the T est button.T o begin the manual output test mode, press and hold the T est button (which causes the green LED to go off) for at least two seconds, then release the button.The green LED blinks, indicating the controller is in manual test mode. The procedur ...
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Trane LO - page 85
UNT -IOM-6 85 T racer ® ZN.520 T able 35. Fan outputs do not energize Probable Cause Explanation Random start observed After power up, the controller always observes a random start from zero to 25 seconds.The controller remains off until the random start time expires. Power up control wait When power up control wait is enabled (non-zero time), the ...
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Trane LO - page 86
T racer ® ZN.520 86 UNT -IOM-6 T able 36. V alves St ay Closed Probable Cause Explanation Requested mode off Y ou can communicate a desired operating mode (such as off, heat, and cool) to the controller . When off is communicated to the controller , the unit controls the fan off. There is no heating or cooling (valves are closed). Power up control ...
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Trane LO - page 87
UNT -IOM-6 87 T erminal Unit Control (TUC) The TUC is capable of operating in either a standalone application or interfacing with a Trane Tracer ® system. In addition, Trane EveryWare ä software is available to edit the configuration of the TUC. The TUC board is easily access- ible on an isolation panel in the control panel. The TUC board will pi ...
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Trane LO - page 88
T erminal Unit Control (TUC) 88 UNT -IOM-6 For TUC controlled units that will interface with the Trane Tracer ® system or Tracer Summit ® building management system, terminate the communication wiring in the control box at the designated terminals on the low voltage terminal strip. Reference the unit wiring schematic or submittals. T ake care to ...
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Trane LO - page 89
UNT -IOM-6 89 T erminal Unit Control (TUC) Establish service communication to the TUC by connecting a twisted wire pair to one of the following connection points. · Remote zone sensor module · Low voltage terminal strip inside the control panel This will allow the technician to view and edit the TUC configuration and troubleshoot the unit. Howeve ...
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Trane LO - page 90
T erminal Unit Control (TUC) 90 UNT -IOM-6 3. Rotate the setpoint dial on the zone sensor module to 55 ° F fo r cooling or 85 ° F for heating. The appropriate control valve will actuate assuming the following conditions: · Room temperature should be greater than 55 ° F and less than 85 ° F · For a 2-pipe fan-coil unit with an automatic change ...
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Trane LO - page 91
UNT -IOM-6 91 T erminal Unit Control (TUC) T able 37. V alid TUC Addresses DI P S wi tc h P os it io n D IP Sw it ch Position Address 1 2 3 4 5 6 7 8 Ad dress 1 2 3 4 5 6 7 8 3 3 X X 6 5 X X 3 4 X X 6 6 X X 3 5 X X X 6 7 X X X 3 6 X X 6 8 X X 3 7 X X X 6 9 X X X 3 8 X X X 7 0 X X X 3 9 X X X X 7 1 X X X X 4 0 X X 72 X X 4 1 X X X 7 3 X X X 4 2 X X ...
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Trane LO - page 92
T erminal Unit Control (TUC) 92 UNT -IOM-6 · Occupied · Unoccupied · Tracer ® with supply fan control Occupied In the occupied mode, the factory configures the TUC for continuous occupied fan cycle. With the fan control set to auto, the fan operates at the required speed to meet the cooling or heating capacity . However , the fan will run at on ...
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Trane LO - page 93
UNT -IOM-6 93 T erminal Unit Control (TUC) high or low temperatures. In addition, the TUC calculates the heating setpoint equal to the cooling setpoint minus an adjustable heating offset. Furthermore, the heating setpoint cannot exceed a value less than or equal to the cooling setpoint. The TUC is in the cooling mode when the space temperature rise ...
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Trane LO - page 94
T erminal Unit Control (TUC) 94 UNT -IOM-6 The entering water temperature sampling function allows water to circulate in an attempt to sense water cold enough to provide cooling. The function uses a timer to permit the controller and the valve to fully open while the water circulates for 3 minutes. The fan continues to run at the selected speed. If ...
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Trane LO - page 95
UNT -IOM-6 95 T erminal Unit Control (TUC) Note: The auxiliary electric heat option is not available with a four-pipe fan-coil unit. Units with manual fresh air dampers ship with the damper in the closed position, which is adjustable from zero to 100 percent in 25 percent incre- ments. T o adjust the position, first remove the air filter to expose ...
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Trane LO - page 96
T erminal Unit Control (TUC) 96 UNT -IOM-6 the outside air temperature falls to 10 ° F or more below the zone temperature. The TUC will control the damper to a position to produce optimal cooling during economizing. If power is interrupted or the TUC is turned off, the damper will spring back to the closed position. If the occupied preheat damper ...
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Trane LO - page 97
UNT -IOM-6 97 T erminal Unit Control (TUC) The low temperature detection option protects the unit from freezing conditions by using a capillary line in the coil fins to detect freezing conditions. The TUC uses the low temperature sensor with a normally open valve. When the sensor detects temperatures below 36 ° F , a binary input turns the fan off ...
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Trane LO - page 98
T erminal Unit Control (TUC) 98 UNT -IOM-6 BIP4: Smoke Input BIP3: Occupied/ Unoccupied Mode BIP1: External Interlock and the electric heat to disable. This creates an immediate shutdown latching diagnostic, which requires a manual or Tracer â reset to resume normal operation. However , normal operation cannot resume until the water level recedes ...
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Trane LO - page 99
UNT -IOM-6 99 T erminal Unit Control (TUC) Autocycle T est The autocycle test is an operating mode that activates the TUC outputs in a defined series of steps. This function allows the techni- cian to to manually exercise each TUC output by sequentially stepping through the 16 stages of the autocycle test Note: Do not leave unit unattended while in ...
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Trane LO - page 100
T erminal Unit Control (TUC) 100 UNT -IOM-6 T able 39. Autocycle T est St aging Stage LEDs (1) F a n - C oil Output Exercised 1 2 3 4 0 Off 1 l Fan low speed 2 l Fan medium speed 3 ll Fan high speed 4 ¡l Economizer/damper 5 ¡l ¡l Cooling valve 6 ¡l l ¡ Heating valve 7 ¡l l l Electric heat stage 1 8 l¡ ¡ ¡ Electric heat stage 2 9 l¡ ¡ l N ...
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Trane LO - page 101
UNT -IOM-6 101 T erminal Unit Control (TUC) Use the TUC human interface to read the current unit diagnostic. If no diagnostics are present, the last diagnostic appears. Perform the following steps. Refer to T able 23 on page 72 for staging details. 1. Read and record the initial TUC address. 2. Set the TUC DIP switch #5 to ON (address = 8). 3. Shor ...
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Trane LO - page 102
T erminal Unit Control (TUC) 102 UNT -IOM-6 Use the human interface to read the unit operating machine state. 1. Read and record the initial TUC address. 2. Set the TUC DIP switch #5 and #8 to ON (address = 9). The remaining switches will be off. 3. Short and hold the test input. 4. The LEDs will blink to define an operating machine state. The oper ...
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Trane LO - page 103
UNT -IOM-6 103 T erminal Unit Control (TUC) T able 41. Operating Machine St ate LED Sequences and Codes S eq ue n ce 1 S e qu en c e 2 Se q ue nc e 3 1 2 3 4 1 2 3 4 1 2 3 4 Code M achine State ¡¡¡¡¡¡¡¡¡¡¡¡ 0 0 Manufacturing T est ¡¡¡¡¡¡¡¡¡¡l 2 Bad Configuration ¡¡¡¡¡¡¡¡¡l ¡¡ 4 Auto Cycle T est ¡¡¡¡¡¡¡¡¡l l ...
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Trane LO - page 104
T erminal Unit Control (TUC) 104 UNT -IOM-6 Using the human interface, read the operating control mode. 1. Read and record the initial TUC address. 2. Set the TUC DIP switch #5 and #7 to ON (address = 10). The remaining switches will be off. 3. Short and hold the test input. 4. The LEDs will blink to define an operating control mode. The operating ...
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Trane LO - page 105
UNT -IOM-6 105 T erminal Unit Control (TUC) Sequence 1 Sequence 2 Sequence 3 Sequence 1 Sequence 2 Sequence 3 1 2 3 4 1 2 3 4 1 2 3 4 ¡¡¡¡ ¡¡¡¡ ¡¡l ¡ ¡ ¡¡l ¡¡¡ l ¡ 5 6 7 5 6 7 5 6 7 T able 42. Operating Control Mode LED Sequences and Codes Sequence 1 Sequence 2 Sequence 3 1 2 3 4 1 2 3 4 1 2 3 4 Co de Control Definition Mode ¡¡? ...
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Trane LO - page 106
T erminal Unit Control (TUC) 106 UNT -IOM-6 T able 42Continued. Operating Control Mode LED Sequences and Codes Sequence 1 Sequence 2 Sequence 3 1 2 3 4 1 2 3 4 1 2 3 4 Code Control Definition Mode ¡¡¡ ¡ ¡¡¡ l ¡¡ l ¡ 1 8 Cool Occupied cooling with the water coil ¡ ¡ ¡ ¡ ¡ ¡ ¡l ¡l ¡ ¡ 20 Cool Occupied cooling with water econo- ...
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Trane LO - page 107
UNT -IOM-6 107 T erminal Unit Control (TUC) T able 43. TUC Controller Diagnostics Diagnostic Latching? F an V alves Elect. Heat Damper Di rt y f il te r Y es No Ac tio n No Action No A ction No Action Condensate Y es Off Closed Off Cl osed overflow Su pp ly f an Y es Of f Closed Of f Cl osed failure (if configured as alarm = yes) Su pp ly fan Y es ...
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Trane LO - page 108
T erminal Unit Control (TUC) 108 UNT -IOM-6 Remove the 24 V AC power from the board and then reapply it to cycle the unit through a power-up sequence. By default, the controller attempts to reset all diagnostics at power-up. The TUC editors reset failure point allows the user to reset controller diagnostics. Also, Tracer ® versions 14.4 and hig ...
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Trane LO - page 109
UNT -IOM-6 109 T erminal Unit Control (TUC) More detailed information about programming and operating the TUC board can be found in Trane publication, EMTX-IOP-1 TUC Installa- tion Operation and Programming Guide. T roubleshooting T able 44. TUC Does Not Communicate Probable Cause Explanation TUC is not addressed correctly V erify the ICS address a ...
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Trane LO - page 110
T erminal Unit Control (TUC) 110 UNT -IOM-6 T able 45Continued. Fan Outputs not Energizing Probable Cause Explanation No power to the TUC The TUC requires 24 V AC power for the unit to operate properly . Autocycle test The controller includes an auto cycle test sequence that verifies analog and binary output operation and associated output wirin ...
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Trane LO - page 111
UNT -IOM-6 111 T erminal Unit Control (TUC) T able 47. V alves Open Probable Cause Explanation Normal Operation The valves open and close to meet unit capacity requirements. Override Present The valves may be overridden to the open position by either the Tracer ® system or by Everyware software. Whenever any override is active, the TUC drives t ...
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Trane LO - page 112
T erminal Unit Control (TUC) 112 UNT -IOM-6 T able 48. Electric Heat Not Operating Probable Cause Explanation Normal Operation The controller cycles electric heat on and off to meet the unit capacity requirements. Unit Disabled The TUC may be disabled via the shutdown mode on a Tracer ® system or if BIP1 is configured as external interlock. Electr ...
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Trane LO - page 113
UNT -IOM-6 113 T erminal Unit Control (TUC) T able 49. Fresh Air Damper Closed Probable Cause Explanation Normal Operation · The two-position fresh air damper opens under normal unit operation during occupied mode and closes during unoccupied mode. · Modulating analog and 3-wire floating point economizers open to the minimum position (configurabl ...
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Trane LO - page 114
T erminal Unit Control (TUC) 114 UNT -IOM-6 T able 50. Fresh Air Damper Open Probable Cause Explanation Normal Operation · The two-position fresh air damper opens under normal unit opera tion during occupied mode and closes during unoccupied mode. · Modulating analog and 3-wire floating point economizers open to the minimum position (configurable ...
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Trane LO - page 115
UNT -IOM-6 115 T able 52. Zone T emperature T oo Cool Probable Cause Explanation Active Heating/Cooling Setpoints V erify that the active heating/cooling setpoints are reasonable. It is possible for either the zone sensor or for the Tracer ® system to send heating and cooling setpoints to the TUC. Use the Tracer ® system or Everyware software ...
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Trane LO - page 116
116 UNT -IOM-6 Listed below are the recommended maintenance schedules. Instruc- tions for specific maintenance procedures are given in the sections following the checklist. WARNING: Allow rotating fan to stop before servicing equipment. Failure to do so may cause severe personal injury or death. Monthly 1. Inspect the unit air filters. Clean or rep ...
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Trane LO - page 117
UNT -IOM-6 117 02 1 x 8.875 x 19.125 1 x 5.5 x 19.13 (2.54 x 23 x 49) (2.54 x 13.97 x 48.59) 03 1 x 8.875 x 19.125 1 x 5.5 x 19.13 (2.54 x 23 x 49) (2.54 x 13.97 x 48.59) Low Vertical 1 x 8.875 x 24.125 (2.54 x 23 x 61) 04 1 x 8.875 x 24.125 1 x 5.5 x 24.13 (2.54 x 23 x 61) (2.54 x 13.97 x 61.29) Low Vertical 1 x 8.875 x 33.625 (2.54 x 23 x 85) 06 ...
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Trane LO - page 118
118 UNT -IOM-6 Clean the fan-coil units main and auxiliary drain pans to ensure the unit drains condensate properly . Check the condensate drain pan and drain line to assure the conden- sate drains properly at least every six months or as dictated by operating experience. If evidence of standing water or condensate overflow exists, immedi- ately ...
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Trane LO - page 119
UNT -IOM-6 119 1 . T o remove the auxiliary drain pan, loosen the hose clamp (inst aller supplied) around the drain con- nection collar and disconnect the drain line. 2. Remove the overflow drain line to the auxiliary drain pan if it was installed. 3. Remove the condensate over- flow switch option from the auxiliary drain pan. 4. Slide the pan hori ...
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Trane LO - page 120
120 UNT -IOM-6 V ertical units : T o remove the main drain pan on vertical fan-coil units, disconnect the clips holding the pan to the fanboard. Disconnect the main and overflow drain hoses and slide pan forward to remove. See Figure 33. Horizontal units: T o remove the main drain pan on a horizontal fan-coil unit, peel the insulation from the edge ...
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Trane LO - page 121
UNT -IOM-6 121 Coils become externally fouled as a result of normal operation. Dirt on the coil surface reduces its heat transfer ability that can result in comfort problems, increased airflow resistance, and thus increased operating energy costs. If the coil surface dirt becomes wet, which commonly occurs with cooling coils, microbial growth (m ...
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Trane LO - page 122
122 UNT -IOM-6 0 2 1 .05 2 .10 3 .14 4 .20 0 3 1 .06 2 .12 3 .18 4 .24 0 4 1 .08 2 .15 3 .23 4 .30 06 1 . 1 1 2 .22 3 .33 4 .44 0 8 1 .14 2 .28 3 .42 4 .56 1 0 1 .18 2 .35 3 .53 4 .71 1 2 1 .21 2 .42 3 .62 4 .83 Note: 1-row coil refers only to the 1-row heating coil in some 4-pipe configurations. Unit Size T otal # Rows V ol um e T able 54. Factory ...
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Trane LO - page 123
UNT -IOM-6 123 The process of cooling and dehumidification produces condensate (water) which must be continuously removed from the air handling unit. The entering air side of the cooling coil to the leaving edge of the drain pan is considered to be the wet section of the unit. Other potentially wet sections are immediately downstream of ...
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Trane LO - page 124
124 UNT -IOM-6 4. Rinse the affected surfaces thoroughly with fresh water and a fresh sponge to prevent potential corrosion of the drain pan and drain line. 5. Ensure the drain line remains open following the cleaning process. 6. Replace all panels and parts and restore electrical power to the unit. 7. Allow the unit to dry completely before puttin ...
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Trane LO - page 125
UNT -IOM-6 125 7. Allow the unit to dry completely before putting it back into service. 8. Do not allow any contaminated material to contact other areas of the unit or building. Properly dispose of all contaminated materials and cleaning solution. If microbial growth (mold) is present, determine the cause of the contamination and take action to pre ...
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Trane LO - page 126
126 UNT -IOM-6 Fan Board Assembly Removal Follow the procedure below when replacing the coil or making repairs to the fan or motor . WARNING: Allow rotating fan to stop before servicing equipment. Failure to do so may cause severe personal injury or death. V ertical Unit s 1. Remove the front panel of cabinet and recessed units. 2. Pull the main an ...
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Trane LO - page 127
UNT -IOM-6 127 After removing the fanboard assembly from the unit, disconnect the fan wheel/wheels from the motor shaft by loosening the Allen head setscrew on the fan wheel hub collar . Next, remove the mounting bolts holding the fan motor plate to the mounting bracket of the fanboard. Then remove the motor by sliding the fan shaft from the fan wh ...
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Trane LO - page 128
128 UNT -IOM-6 Appendix Factory Piping Packages Automatic Circuit Setter (C) ...
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Trane LO - page 129
UNT -IOM-6 129 For reference only: This schematic show typical wiring of a fan-coil. It is not intended for a basis of design or for equipment installation purposes in the field. For an as-built schematic specific to a particular unit, please see the ship-with schematic for that specific unit. Fan Mode Switch T ypical Wiring Diagram For Reference O ...
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Trane LO - page 130
130 UNT -IOM-6 NOTES: 1. UNLESS OTHERWISE NOTED, ALL SWITCHES ARE SHOWN A T 25 C (77 F), AT ATMOSPHERIC PRESSURE, A T 50% RELA TIVE HUMIDITY , WITH ALL UTILITIES TURNED OFF , AND AFTER A NORMAL SHUTDOWN HAS OCCURRED. 2. DASHED LINES INDICA TE RECOMMENDED FIELD WIRING BY OTHERS. DASHED LINE ENCLOSURES AND/OR DASHED DEVICE OUTLINES INDICA TE COMPONEN ...
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Trane LO - page 131
UNT -IOM-6 131 T racer ® ZN.010 T ypical Wiring Diagram For Reference Only: This schematic shows typical wiring of a fan-coil. It is not intended for a basis of design or for equipment installation purposes in the field. For an as-built schematic specific to a particular unit, please see the ship-with schematic for that specific unit or contact yo ...
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Trane LO - page 132
132 UNT -IOM-6 For Reference Only: This schematic shows typical wiring of a fan-coil. It is not intended for a basis of design or for equipment installation purposes in the field. For an as-built schematic specific to a particular unit, please see the ship-with schematic for that specific unit or contact your local T rane representative. Four-pipe ...
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Trane LO - page 133
UNT -IOM-6 133 TUC T ypical Wiring Diagram For Reference Only: This schematic shows typical wiring of a fan-coil. It is not intended for a basis of design or for equipment installation purposes in the field. For an as-built schematic specific to a particular unit, please see the ship-with schematic for that specific unit or contact your local T ran ...
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Trane LO - page 134
134 UNT -IOM-6 TUC T ypical Wiring Diagram For Reference Only: This schematic shows typical wiring of a fan-coil. It is not intended for a basis of design or for equipment installation purposes in the field. For an as-built schematic specific to a particular unit, please see the ship-with schematic for that specific unit or contact your local T ran ...
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Trane LO - page 135
UNT -IOM-6 135 ...
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Trane LO - page 136
The T rane Company Worldwide Applied Systems Group 3600 Pammel Creek Rd. LaCrosse, WI 54601-7599 www.trane.com An American Standard Company Literature Order Number UNT - IOM-6 File Number PL-TD- UNT -IOM-6-4-00 Supersedes UNT -IOM-5 Stocking Location LaCrosse Since The T rane Company has a policy of continuous product improvement, it reserves the r ...
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