Service & Parts Manual (2019, 2020, 2021, 2022)
Table Of Contents
- INTRODUCTION
- SPECIFICATIONS
- OPERATION
- ROUTINE MAINTENANCE
- REMOVE AND INSTALL THE CHASSIS
- R-410A SEALED SYSTEM REPAIR
- COMPONENT TESTING
- Hermetic Components Check
- Reversing Valve Description And Operation
- Testing The Reversing Valve Solenoid Coil
- Checking The Reversing Valve
- Replace The Reversing Valve
- Touch Test Chart : To Service Reversing Valves
- Compressor Checks
- Compressor Replacement
- Fan Motor
- Capacitors
- Heating Element
- Drain Pan Valve
- Testing the User Interface and Electronic Control Board
- Thermistors Description
- Electronic Control Board Identification
- Replace the Electronic Control Board
- Replace the User Interface
- TROUBLESHOOTING
- WIRING DIAGRAMS
- PARTS CATALOG
- Available Accessories
34 PB
OPERATION
Unit Cooling Mode
Once the ambient temperature rises past the cool demand threshold (Cool Set Point + 1.5 ˚F) (see gure below),
and the compressor is not locked out, the cooling cycle begins. As shown in the gure below, the fan is started 5
seconds prior to the compressor. Once the ambient temperature has been lowered to the cool set point (Cool Set
Point minus .25 ˚F), the cooling cycle starts to terminate by shutting off the compressor. After a 30 seconds delay,
the fan is shut off. (See gure below for graphic details)
Unit Heating Mode Control Operation
There are two heating methods: Heat Pump and Electric Resistance Heat.
There are 2 types of units that provide heating:
Heat Pump with Electric Heat (WHT12A33A)
Cool with Electric Heat (WET10A33A, WET12A33A, WET16A33A)
Figure 339 (Cooling Control )