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B.
Use of the crankcase heater
The crankcase heater is installed around the lower part of the compressor and
shall be turned on all the time. The heater is self-regulated.
3. Piping, Checking and Testing
NOTES:
•
The line connection sizes of liquid filter & indicator, the valve
connection sizes of condensing unit and the line connection sizes of
evaporator unit are not necessary the same as the listed refrigeration
line sizes.
•
If the condensing unit is installed above the evaporator unit, use the
suction line one listed size smaller.
•
Expansion and solenoid valves have been installed on the liquid line in
the evaporator unit.
1) The installation order starts from condensing unit (including receiver and
discharge valve), liquid line filter-drier, moisture-liquid indicator, liquid line, to
evaporator unit (including liquid line connection, solenoid valve, expansion
valve, and suction line connection), returning to insulated suction line, suction
valve and then back to condensing unit.
2) Use inverted U trap to prevent liquid from flooding back to the compressor.
3) Complete pipe brazing, check solenoid valve and expansion valve restrictions
and test leak
The line sizes and refrigerant charges are listed as follows.
Model No
Liquid Line
Suction Line
Recommended Charge
WM-4500DS
1/4" OD
1/2” OD
R134a/26 OZ
WM-6500DS
1/4" OD
1/2” OD
R134a/32 OZ
WM-8500DS
3/8" OD
5/8” OD
R134a/40 OZ
2. Connecting Electrical Wires
Connect all electrical components using the wiring diagrams in accordance with
all state and local codes.
4. Evacuating, Charging and Starting the system
CAUTION:
•
Always use the superheat and subcooling, pressure readings to charge
refrigerant properly; the listed charge amounts are used for reference
only.
•
If the unit is equipped with a low ambient condition kit and installed in
the summer, charge 15% more refrigerant.
