United CoolAir VariCool EZ-Fit Series, Installation, Operation And Maintenance Manual

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Installation, Operation and Maintenance Manual
VariCool EZ-Fit
32
Subject to change without notice.
PROBLEM POSSIBLE CAUSE POSSIBLE SOLUTION
Suction
pressure
too low
1� Flash gas in liquid line
2� Obstructed expansion valve
3� Loss of fluid in expansion valve bulb
4� Clogged filter drier
5� Lack of air flow
6� Entering WB too low
7� Evaporator blower running
backwards
1� Check for refrigerant leak
2� Repair leak, evacuate and recharge refrigerant
system
3� Replace thermal expansion valve
4� Replace filter drier
5� Check filters and coil for any blockages
6� Verify that blower is rotating in the proper direction
7� Confirm that entering return air conditions fall within
acceptable range
8� Reset low pressure safety switch if necessary
9� Check phase of incoming power to unit Reverse any
two incoming power supply wires (except ground)
No cooling 1� Controller not set properly
2� Control wiring issue
3� Controls in an alarm condition
4� High or low pressure switch open
5� Compressor thermal overload open
1� Turn on and set controller for desired operation
2� Check wiring connections against schematic
3� Check all connections for tightness
4� Check wire continuity
5� Refer to controller troubleshooting
6� Reset high or low pressure switch
7� Compressor internal overload may require an
extended period of time (1 hour or more) to reset
Condensate
carry over
1� Air flow too high 1� Reduce air flow
Condensate
pump does
not run
1� Check to see that power to the
pump is present
2� Confirm that float is moves freely
3� Confirm that dirt or algae is not
interfering with float action
1� Locate and repair electric issue
2� Clean float and sump
Condensate
pump runs
with no
discharge
1� Tubing blocked or kinked
2� Check valve blocked
3� Impeller blocked
4� Tubing elevation or run exceeds
head capability
1� Inspect, clean or straighten as necessary
2� Clean check valve
3� Remove debris from pump impeller
4� Verify tubing run is within pump head limitations