Carrier 50PEC09-18 Heat Pump User Manual


 
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Checking System Charge — Units are shipped with
full operating charge. If recharging is necessary:
1. Insert thermometer bulb in insulating rubber sleeve on
liquid line near filter drier. Use a digital thermometer for
all temperature measurements. DO NOT use a mercury
or dial-type thermometer.
2. Connect pressure gage to discharge line near compressor.
3. After unit conditions have stabilized, read head pressure
on discharge line gage.
NOTE: Operate unit a minimum of 15 minutes before
checking charge. From standard field-supplied Pressure-
Temperature chart for R-410A, find equivalent saturated
condensing temperature.
4. Read liquid line temperature on thermometer, then
subtract from bubble point temperature. The difference
equals subcooling temperature.
Refrigerant Charging
NOTE: Do not vent or depressurize unit refrigerant to atmo-
sphere. Remove and recover refrigerant following accepted
practices.
Air Coil Fan Motor Removal
Motor power wires need to be disconnected from motor
terminals before motor is removed from unit.
1. Shut off unit main power supply.
2. Loosen bolts on mounting bracket so that fan belt can be
removed.
3. Loosen and remove the 2 motor mounting bracket bolts
on left side of bracket.
4. Slide motor/bracket assembly to extreme right and lift out
through space between fan scroll and side frame. Rest
motor on a high platform such as a step ladder. Do not
allow motor to hang by its power wires.
Replacing the WSHP Open Controller’s Bat-
tery —
The WSHP Open controller’s 10-year lithium
CR2032 battery provides a minimum of 10,000 hours of data
retention during power outages.
NOTE: Power must be ON to the WSHP Open controller
when replacing the battery, or the date, time and trend data will
be lost.
1. Remove the battery from the controller, making note of
the battery's polarity.
2. Insert the new battery, matching the battery's polarity
with the polarity indicated on the WSHP Open controller.
TROUBLESHOOTING
When troubleshooting problems with a WSHP, consider the
following and refer to Table 18.
Thermistor — A thermistor may be required for single-
phase units where starting the unit is a problem due to low
voltage.
WSHP Open Controller — With the WSHP Open con-
troller option, the 100 most recent alarms can be viewed using
the BACview
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alarm status and alarm history.
To view the alarms:
1. Navigate to the Alarm Status screen from the Home
screen using the arrow softkeys. The screen will display
the current alarm status, either normal or Alarm, and al-
low for scrolling through the unit’s alarm status.
2. From the Alarm Status screen, press the Alarm softkey to
view the 100 most recent alarms which are labeled with
date and time for easy reference.
NOTE: Active faults can be viewed by scrolling down,
these faults indicate a possible bad sensor or some condi-
tion which may not merit an alarm.
3. To view alarms which have been corrected, scroll down
through the Alarm screen to Return Top Normal screen.
NOTE: Alarms are automatically reset once alarm con-
dition has been corrected.
See Table 18 for possible alarm cause and solution.
WARNING
To prevent personal injury, wear safety glasses and gloves
when handling refrigerant. Do not overcharge system —
this can cause compressor flooding.
CAUTION
Before attempting to remove fan motors or motor mounts,
place a piece of plywood over evaporator coils to prevent
coil damage.