Vogt P18AL TUBE-ICE, Service Manual

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P18AL Service Manual
TROUBLESHOOTING
3/6/07
8-5
Symptom: Poor ice quality
Possible Cause Possible Remedy
Excessive concentration of solids in the water tank usually
indicated by a build-up of mineral deposit on the sides and
bottom of the tank and opaque ice production. Also, water
distributors restricted. Perform a cleaning procedure as well as removing the freezer
cover and cleaning the water distributors. Make sure the
flushing valve (27) is functioning and the tank overflow piping
is not restricted.
Insufficient water supply indicated by a low level in the tank Check water pressure, 30 psig is recommended minimum.
Check for a water line restriction, partially closed valve, or
defective make-up water float valve. Make sure the water tank
drain is closed.
Water pump rotation wrong direction Check rotation in relation with arrow on pump housing and
reverse two wires at the motor if necessary.
Low refrigerant charge, causing an ice out problem and re-
freeze Check refrigerant level mark on the receiver and on the painted
portion of the gage glass guard. Be sure to keep the gage glass
cocks closed when finished checking the level.
Suction Pressure to low Adjust suction regulator valve
Restriction in liquid line, causing short freeze cycle Check for closed valve, defective solenoid valve (25), float
switch defective or strainer restricted. The liquid line will
normally have frost on the down-stream side of a restriction,
especially as the suction pressure decreases.
Symptom: High discharge pressure (check gage accuracy)
Possible Cause Possible Remedy
Insufficient water flow through the cooling tower or condenser Check the condenser water pump to make sure it is pumping
enough water. Check sump strainer screen and clean. Check
condenser pump direction of rotation.
Fan control out of adjustment Check adjustment. Replace if defective.
Non-condensable in system. If non-condensables are present with the refrigerant, the
saturated temperature will not relate to the pressure reading at
the receiver. The refrigerant will be cooler, although the
pressure will be high. Air can be purged from the system by
following instructions in Section 9, “Purging Non-
Condensables”.
Cooling tower or evaporative condenser requires maintenance Check fan motor and fan belts for proper operation and
tension. Check spray nozzles, tubes, sump, and sump screen,
for accumulation of mineral deposit and clean as required.
Check tower blowdown and chemical treatment if applicable.
Dirty condenser tubes Visually inspect the condenser tubes to see if there is any
build-up of mineral deposits which would reduce the cooling
effect of the tubes and water. Clean chemically or
mechanically as applicable.
Symptom: Low discharge pressure (check gage accuracy)
Possible Cause Possible Remedy
Fan cycling switch out of adjustment or defective Check adjustment. Replace if defective.
Compressor running unloaded or not pumping efficiently Check compressor motor amp. If the compressor is running
unloaded, the amperage will only be approximately 60% of
normal amp draw (FLA). Refer to the compressor manual.
Ambient temperature low and prevailing winds blowing
through tower Shield tower from prevailing winds to prevent excessive
cooling. Install an indoor sump.
Too much cold water circulating through condenser Install a water regulating valve in the water line form the
condenser and control flow by receiver pressure.
Thaw gas valve (18) leaking through Make sure manual opening stem is in the automatic (screwed
in) position. Repair or replace defective parts.