Trane CGA-SVX01A-EN - Compressor is Noisy; System Short of Capacity

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CGA-SVX01A-EN
G. Compressor is Noisy
Probable Cause
(1) Internal parts of compressor damaged or broken (compressor
knocks)
(2) Liquid floodback (indicated by abnormally cold suction line and
low superheat)
(3) Liquid refrigerant in compressor at start-up (indicated by
abnormally cold compressor shell)
Recommended Action
Replace compressor
Check and adjust superheat
Check for refrigerant overcharge
H. System Short of Capacity
Probable Cause
(1) Low refrigerant charge (indicated by high superheat and low
subcooling)
(2) Clogged filter drier (indicated by temperature change in
refrigerant line through drier)
(3) Incorrect expansion valve setting
(4) Expansion valve stuck or obstructed(i.e., high superheat and
high water temperature)
(5) Low evaporator water flow
(6) Noncondensibles in system
(7) Leaky valves in compressor (i.e., operation at abnormally high
suction and low discharge pressures)
Recommended Action
Add refrigerant
Replace filter drier or filter drier core
Readjust expansion valve
Repair or replace expansion valve
Check strainers. Adjust water flow
Evacuate and recharge system
Replace compressor
I. Suction Pressure Too Low
Probable Cause
(1) Shortage of refrigerant (i.e., high superheat, low subcooling)
(2) Thermostat set too low (i.e., low discharge pressure, low leaving
water temperature)
(3) Low water flow
(4) Clogged filter drier
(5) Expansion valve power assembly has lost charge
(6) Obstructed expansion valve (i.e., high superheat)
Recommended Action
Find and repair leak; recharge system
Readjust thermostat
Check for clogged strainers and ncorrect balancing valve settings
Check for frost on filter drier. Replace if needed
Repair or replace expansion valve power head assembly
Clean or replace valve
J. Suction Pressure Too High
Probable Cause
(1) Excessive cooling load (i.e., high supply water temperatures)
(2) Expansion valve overfeeding (i.e.,superheat too low, liquid
flooding to compressor)
(3) Suction valves broken (i.e. noisy compressor)
Recommended Action
See (E) above
Adjust superheat setting; verify that remote bulb is properly attached
to suction line
Replace compressor