The Thermax system allows the complete unit charge to be available during heat. Truck units with TherMax have had some components of the standard 3-way…

Purpose: To test the heat exchanger for an internal high side to low side leak. NOTE: To prevent refrigerant loss to the atmosphere, recovery equipment…

Purpose: This check confirms the expansion valve setting and operation and enables the technician to make adjustments if required. NOTE: Perform low side pumpdown, compressor…

1. Momentarily energize the pilot solenoid to shift the 3 way valve. NOTE: On late 1989 and newer units the pilot solenoid must remain energized…

1. Front seat the condenser pressure bypass check valve. 2. Operate the unit in high speed cool and cover the condenser coil to build discharge…

Purpose: To test the condenser check valve, the condenser side of the 3-way valve and the condenser pressure bypass check valve on units with heat…

Check compressor oil condition by observing its color during each major service or system repair. Test a sample of compressor oil for acid contamination. If…

Purpose: To check compressor oil level, oil condition and oil pressure. Oil Level Check Procedure 1. Warm the unit evaporator by operating the unit with…

Purpose: To test compressor piston reed condition, piston to cylinder clearance, piston and cylinder condition, and compressor performance capability. Preparations Before the Test 1. Ambient…

Pump down the compressor and adjust pressures slightly positive (1 to 2 psig) to perform the following service: 1. Add or remove compressor oil. 2.…