No Power
Check that the master power switch is on. (located next to the Carel
Controller)
Carel Electronic Thermostat
(located behind lift up cover)
above the light switch on the top
of the base of the unit.)
Check to see that the control is turned on.
Control Display Is Flashing -
If the control is flashing all of its lights, it is
likely that you have a grounding issue with the power source. Verify that
the unit is properly grounded.
Check to see if the compressor run indicator is on, calling for cooling.
Defrost Mode
Is the unit entering into defrost too often, or staying in defrost to long? Our
cases typically defrost every 6 to 8 hours as long as the evaporator sensor
is below defrost termination temperature of approximately 43°F. There is
also a defrost on demand feature that can supersede the normal defrost
interval as
needed. – 30 minute maximum, defrost duration.
Check Set Point Temperature; it # 1 is the warmest and # 9 is the coldest –
set typically between 4 & 5 – adjust accordingly – control has a minimum
run time of 5 minutes and a maximum run of 75 minutes (self-contained
units) and 60 minutes (remote condensing unit).
Supply Air Temperature – Press & Hold Down (Defrost) immediately
followed by Up (Power) – You must keep them both held to see the
temperature.
Check the return air grill inside unit for obstructions.
Check that the top air discharge diffuser is not blocked with dust or debris.
The airflow should be approximately 200 fpm.
Check that the condenser air inlet and condenser air outlet are not
restricted.
Check that all evaporator fan motor and blades are working as they should.
Check that the condenser fan motor and blade are working as they should.
Check that the evaporator is clear and not obstructed with ice or debris
Check TXV bulb installation is secure and insulated.
Check that superheat is between 8°F to 12°F
.
If equipped, check sight glass for flashing and/or low charge.
Compressor Is Not
Operating
Check the electronic temperature control to see if the unit has the
compressor indicator illuminated.
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