Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 53 of 83
Component Testing
Component Testing Table of Contents
Verifying High Pressure Switch and Low Pressure
Protection Operation..................................................51
Verifying Suction Pressure Transducer Operation.....52
Verifying Liquid Pressure Transducer Operation .......53
High Pressure Switch and Low Pressure Protection
Errors .........................................................................54
Compressor Operation, Checkout and Status / Error
Codes ........................................................................54
Compressor Equalization Valve .................................56
Crankcase Heater, Checkout and Status / Error Codes
...................................................................................61
Suction Line Filter Drier .............................................62
Liquid Line Filter Drier ..............................................62
Top Cap Switch Operation, Checkout and Status / Error
Codes ........................................................................63
Reactor Operations, Checkout and Status / Error Codes
...................................................................................64
Outdoor Fan Operation and Checkout ......................64
Outdoor Control Operation, Checkout and Status / Error
Codes ........................................................................66
Unit Sensor Operation, Checkout and Status /Error
Codes ........................................................................69
DC Inverter Control Operation, Checkout, Status / Error
Codes ........................................................................72
Verifying High Pressure Switch and Low Pressure Protection Operation
OPERATION:
The unit’s pressure switches (HPS - S4 and LPS-S87) are wired into the the control HPS and LPS terminals, respectively.
NOTE:
The HRG18 does not have a low pressure switch and LPS terminals are not jumpered. The unit has a suction
pressure transducer that emulates the low pressure switch with a cut-out of 40 PSIG and a cut-in of 90 PSIG. This provides
the same protection as a tradition low pressure switch. If the event the suction pressure transducer fails, back up protection
is provided by the suction temperature sensor and will open at 25F.
•
Low Suction Pressure Switch (LPS) – See Figure 25 for low suction pressure protection sequence of operation.
•
High Pressure Switch (HPS) – See Figure 25 for high pressure switch sequence of operation.
Pressure Switch Event Settings
The following pressures are the auto-reset event value triggers for low and high pressure thresholds:
•
High Pressure (auto-reset) - trip at 590 psig; reset at 418.
•
Low Pressure (auto-reset) – trip at 25 psig; reset at 40.
Checkout – S4 High Pressure Switch
Using a multimeter set to ohms with the terminals disconnected from the control board, check the resistance between the
two terminals of the pressure switch. If the resistance reading is 0 ohms, the switch is closed.
S4
HIGH
PRESSURE
SWITCH
S87
LOW
PRESSURE
SWITCH
Figure 25. Verifying High and Low Pressure Switch Operation