Trane Service Facts

Important Information & Warnings

❗ CAUTION: UNIT CONTAINS R-410A REFRIGERANT! R-410A OPERATING PRESSURE EXCEEDS THE LIMIT OF R-22. PROPER SERVICE EQUIPMENT IS REQUIRED. FAILURE TO USE PROPER SERVICE TOOLS MAY RESULT IN EQUIPMENT DAMAGE OR PERSONAL INJURY.

SERVICE: USE ONLY R-410A REFRIGERANT AND APPROVED POE COMPRESSOR OIL.

IMPORTANT: This document contains a wiring diagram, a parts list, and service information. This is customer property and is to remain with this unit. Please return to service information pack upon completion of work.

⚠️ WARNING: HAZARDOUS VOLTAGE - DISCONNECT POWER AND DISCHARGE CAPACITORS BEFORE SERVICING.

Product Specifications

Notes:

• ¹ Certified in accordance with the Air-Source Unitary Air-conditioner Equipment certification program, which is based on AHRI standard 210/240.
• ² Rated in accordance with AHRI standard 270.
• ³ Calculated in accordance with Natl. Elec. Codes. Use only HACR circuit breakers or fuses.
• ⁴ Standard Air -- Dry Coil -- Outdoor
• ⁵ This value is approximate. For more precise value see unit nameplate.
• ⁶ Max. linear length 60 ft.; Max. lift - Suction 60 ft.; Max lift - Liquid 60 ft. For greater length consult refrigerant piping software Pub. No. 32-3312-0* (* denotes latest revision).
• ⁷ This value shown for compressor RLA on the unit nameplate and on this specification sheet is used to compute minimum branch circuit ampacity and max. fuse size. The value shown is the branch circuit selection current.
• ⁸ No means no start components. Yes means quick start kit components. PTC means positive temperature coefficient starter.

Tubing Information

Tubing lengths in excess of sixty (60) feet see application software.

Service Information

❗ CAUTION: HOT SURFACE! DO NOT TOUCH TOP OF COMPRESSOR. May cause minor to severe burning.

❗ CAUTION: CONTAINS REFRIGERANT! SYSTEM CONTAINS OIL AND REFRIGERANT UNDER HIGH PRESSURE. RECOVER REFRIGERANT TO RELIEVE PRESSURE BEFORE OPENING SYSTEM. Failure to follow proper procedures can result in personal illness or injury or severe equipment damage.

⚠️ WARNING: THIS INFORMATION IS INTENDED FOR USE BY INDIVIDUALS POSSESSING ADEQUATE BACKGROUNDS OF ELECTRICAL AND MECHANICAL EXPERIENCE. ANY ATTEMPT TO REPAIR A CENTRAL AIR CONDITIONING PRODUCT MAY RESULT IN PERSONAL INJURY AND OR PROPERTY DAMAGE. THE MANUFACTURER OR SELLER CANNOT BE RESPONSIBLE FOR THE INTERPRETATION OF THIS INFORMATION, NOR CAN IT ASSUME ANY LIABILITY IN CONNECTION WITH ITS USE.

❗ CAUTION: RECONNECT ALL GROUNDING DEVICES. ALL PARTS OF THIS PRODUCT CAPABLE OF CONDUCTING ELECTRICAL CURRENT ARE GROUNDED. IF GROUNDING WIRES, SCREWS, STRAPS, CLIPS, NUTS OR WASHERS USED TO COMPLETE A PATH TO GROUND ARE REMOVED FOR SERVICE, THEY MUST BE RETURNED TO THEIR ORIGINAL POSITION AND PROPERLY FASTENED.

NOTICE: Trane has a policy of continuous product and product data improvement and it reserves the right to change design and specifications without notice. © 2010 Trane

Schematic Diagram Description

The schematic diagram illustrates the electrical connections and components of the split system. Key components include the compressor, outdoor fan motor, capacitors, contactors, relays, and various safety switches and sensors (e.g., High Pressure Cutout - HPCO, Outdoor Fan Thermostat - OFT, Outdoor Temperature Sensor - ODS, Outdoor Thermostat - ODT). It shows connections from the power supply to the unit's main components and control circuits, including low voltage wiring for thermostat control.

Subcooling Charging in Cooling Above 55°F OD Ambient

Trane recommends installing matched indoor and outdoor systems for optimal efficiency and reliability. For split systems with indoor TXVs (Thermostatic Expansion Valves), subcooling is the recommended charging method when the outdoor ambient temperature is above 55°F.

Procedure:

1. Maintain indoor temperature between 70°F to 80°F. Add system heat if necessary.
2. Ensure the system operates for a minimum of 20 minutes to stabilize before taking measurements.
3. Measure Liquid Line Temperature and Refrigerant Pressure at the service valves.
4. Determine the total refrigerant line length and any vertical height difference (lift) if the indoor section is above the condenser.
5. Identify the Design Subcool Charging Temperature from the unit's nameplate.
6. Locate the appropriate column in the Subcooling Charging Table corresponding to the Design Subcool value.
7. Find the measured Liquid Line Temperature in the left column of the table. The intersecting value under the Design Subcool column indicates the target Liquid Gage Pressure.
8. Add refrigerant to increase pressure or remove refrigerant to decrease pressure until the target pressure is reached. Wait 20 minutes for system conditions to stabilize after adjustments.
9. Refer to the System Pressure Curves for performance verification once the system is correctly charged.

Subcooling Charging Chart Corrections Table (for Line Length and Rise)

This table is used to determine corrections to the target subcool value based on refrigerant line length and vertical rise. It features columns for total refrigerant line length (ranging from 0 to 80 feet) and rows for refrigerant line lift (ranging from 0 to 60 feet). The values within the table specify the amount (in °F) to add to the design subcool value based on the specific line length and lift conditions.

Wiring Diagram

The wiring diagram details the electrical connections for the unit. It includes a legend for various symbols representing components like capacitors, relays, switches, motors, and wiring types (factory vs. field). The diagram shows the main power input, the connections to the compressor contactor (MS), compressor motor, fan motor, and control circuits, including connections for optional remote sensors like ODT-A and ODT-B.

Legend Symbols:

• [24V Factory Wiring]
• [24V Field Wiring]
• [Factory Wiring]
• [Field Installed Wiring]
• [Magnetic Coil]
• [Ground]
• [Junction]
• [Capacitor]
• [Wire Nut or Terminal]
• [Transformer]
• [Fuse]
• [Terminal Block/Board]
• [Relay Contact (N.O.)] - Normally Open
• [Relay Contact (N.C.)] - Normally Closed
• [Thermistor]
• [Temp Actuated Switch]
• [Internal Overload Protection]
• [Pressure Actuated Switch]
• [Resistor or Heating Element]
• [Motor Winding]
• [Plug/Socket]

R-410A Refrigerant Charging Chart

This chart provides target Liquid Gage Pressure (PSI) based on Liquid Temperature (°F) for different Design Subcoolings (°F).

Refer to Service Facts or Installer's Guide for charging method.

Troubleshooting

Compressor Fails to Start

Follow these steps if the compressor does not start:

• Check Contactor: Verify if the contactor is energized (contacts closed).
• If YES: Go to "Compressor won't run" section.
• If NO: Check for 24 volts AC across the contactor coil.
• If voltage is present: Replace the contactor.
• If voltage is NOT present: Check the control transformer and control fuse.
• If control transformer and fuse are good: Jumper R to Y low voltage terminals at the thermostat sub-base.
• If the contactor energizes after jumper: Replace the room thermostat.
• If the control transformer or fuse is faulty: Repair or replace the transformer or fuse. Investigate the cause for failure (possible short in field wiring).
• If the contactor does not energize after jumper: Repair or replace connecting wiring.

Compressor Won't Run (Contactor is Closed)

Follow these steps if the compressor does not run but the contactor is closed:

• Check for high voltage to the contactor at terminals T1 and T2.
• If high voltage is present: Check for an open IOL (Internal Overload). Measure resistance from C to S and C to R. If the resistance check shows an open circuit from C to S or C to R, replace the compressor.
• If high voltage is NOT present: Check power supply from the disconnect and/or breaker panel.
• If the resistance check shows an open circuit between R and S: Check for open windings. Replace the compressor.
• If no open windings are found: Check for a locked rotor. Measure voltage at C to S and C to R with locked rotor amps on C.
• If voltage is present with locked rotor amps: Check the Start Capacitor and Relay (if present) and the Run Capacitor. If start components and run capacitor check good, replace the compressor. If they do not check good, replace start components and/or run capacitor.
• If voltage is NOT present with locked rotor amps: Check wiring to compressor C, S, and R.

Contactor Types:

Single Pole Contactor (MS)*

Terminals: IN, OUT, T2, T1. Coil: 24 VAC. High Voltage connection.

Double Pole Contactor (MS)*

Terminals: IN, OUT, T2, T1. Coil: 24 VAC. High Voltage connection.

*Refer to Wiring Diagram to determine if a single pole or double pole contactor is used.

Refrigerant Circuit

The refrigerant circuit diagram illustrates the flow of refrigerant through the system. It includes the indoor section with the indoor coil, check valve, and expansion valve (or FCCV), and the outdoor section with the compressor, dryer, and outdoor coil. The interconnecting tubing consists of the suction line and the liquid line. Pressure taps are located on the suction and liquid lines for service measurements. Refrigerant flows from the indoor coil, through the expansion device, to the compressor suction, then through the compressor, to the discharge line, through the dryer, and finally to the outdoor coil.

Pressure Curves for Cooling Performance

These curves help in checking cooling performance when the outdoor temperature is above 65°F.

How to Use the Plots:

1. Select the proper indoor CFM.
2. Allow system pressures to stabilize.
3. Measure the Indoor Wet Bulb Temperature, Outdoor Temperature, Liquid Pressure, and Suction Pressure.
4. On the plots:
   • Locate the Outdoor Temperature on the horizontal axis (1).
   • Locate the Indoor Wet Bulb Temperature on the vertical axis (2).
   • Find the intersection point of the Outdoor Temperature and Indoor Wet Bulb Temperature curves (3).
   • Read the corresponding Liquid Pressure (4) or Suction Pressure (5) from the left vertical axis.

Example:

• Outdoor Temp: 82°F (1)
• Indoor Wet Bulb: 67°F (2)
• Intersection Point (3)
• Liquid Pressure @ 825 CFM: 303 PSIG (4)
• Suction Pressure @ 825 CFM: 137 PSIG (5)

Actual Performance Check:

• Actual Liquid Pressure should be within +/- 10 PSI of the chart value.
• Actual Suction Pressure should be within +/- 3 PSIG of the chart value.

Interconnecting Lines:

• Gas Line: 5/8" O.D.
• Liquid Line: 3/8" O.D.