United CoolAir VariCool EZ-Fit Series, Инструкция по установке, эксплуатации и обслуживанию

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Installation, Operation and Maintenance Manual
VariCool EZ-Fit
31
Subject to change without notice.
PROBLEM POSSIBLE CAUSE POSSIBLE SOLUTION
Evaporator
coil ices
1�
Lack of air flow
2�
Low return air temperature
3�
Loss of refrigerant charge
4�
VFD not functioning properly
1�
Check filters and coil for any blockages
2�
Replace filters if dirty
3�
Verify that blower is rotating in the proper direction
4�
Make sure that supply air is not short cycling back into return
air stream
5�
Repair leak, evacuate and recharge refrigerant system
Noisy
compressor
1�
Expansion valve stuck open
2�
Worn or scarred compressor
bearings
3�
Excessive head pressure
4�
Broken compressor valve
(compressor knocking)
5�
Liquid slugging
1�
Ensure thermal expansion valve bulb is tight on suction line
2�
Confirm thermal expansion valve bulb is located properly on
suction line
3�
Check superheat
4�
Replace compressor
5�
Reduce head pressure
6�
System overcharged Reclaim excess refrigerant from the
high side of the system
System short
of capacity
1� Flash gas in liquid line
2� Expansion valve stuck open or
possibly obstructed
3� Clogged filter drier
4� Iced or clogged evaporator coil
5� Head pressure control valve not
operating properly
6� Condenser needs cleaned
1� Check for refrigerant leaks
2� Repair leak, evacuate and recharge refrigerant system
3� Check sub-cooling
4� Ensure thermal expansion valve bulb is tight on suction line
5� Confirm thermal expansion valve bulb is located properly on
suction line
6� Replace thermal expansion valve
7� Replace filter drier
8� Check filters and coil for any blockages
9� Replace filters if dirty
10� Verify that blower is rotating in the proper direction
11� Confirm proper fluid flow quantity through condenser
12� Confirm acceptable fluid temperatures entering the condenser
13� Clean condenser
Head
pressure
too high
1� Possible non-condensible in
system
2� Overcharge of refrigerant
3� Condenser water flow not
adequate
4� Condenser entering fluid
temperature too hot
5� Condenser air intake, duct or
coil blocked
6� Condenser blower not operating
or running backwards
1� Repair leak, evacuate and recharge refrigerant system
Install new filter drier
2� Reclaim excess refrigerant from high side of system
3� Confirm proper fluid flow quantity through condenser
4� Confirm acceptable fluid temperatures entering the condenser
5� Verify that head pressure control valve is operational
6� Reset high pressure safety switch if tripped
7� Clean away debris from condenser air circuit
8� Check phase of incoming power to unit Reverse any two
incoming power supply wires (except ground)
Head
pressure
too low
1� Condenser water flow too high
2� Entering fluid temperature too
low
3� Excessive air flow across
condenser
1� Confirm proper fluid flow quantity through condenser
2� Confirm acceptable fluid temperatures entering the condenser
3� Confirm proper air flow amount Adjust blower drive package
as necessary