Therma-Stor Products Group 300 User Manual

Page of 11
5
www.thermastor.com • sales@thermastor.com
Toll-Free 1-800-533-7533
coil where it absorbs heat from the incoming air and 
evaporates.
The evaporator operates in a flooded condition, which 
means that all the evaporator tubes contain liquid 
refrigerant during normal operation. A flooded evaporator 
should maintain constant pressure and temperature 
across the entire coil, from inlet to outlet.
The mixture of gas and liquid refrigerant enter the 
accumulator after leaving the evaporator coil. The 
accumulator prevents any liquid refrigerant from reaching 
the compressor. The compressor evacuates the cool 
refrigerant gas from the accumulator and compresses it to 
a high pressure and temperature to repeat the process.
4.3 Troubleshooting
No dehumidification. Neither blower or compressor run. 
Power switch does not light when ON.
.  Unit unplugged or no power to outlet.
2.  Power switch defective (Sec. 2.6).
3.  Loose connection in internal wiring (Fig. 3).
No dehumidification. Neither blower or compressor run. 
Power switch ON and lit.
.  Low pressure control open (Sec. 2.).
2.  Power switch defective (Sec. 2.6).
3.  Loose connection in internal wiring (Fig. 3).
Some dehumidification, blower runs continuously but 
compressor only runs sporadically.
.  Unit is in defrost cycle (Sec. 2.0 and 4.7).
2.  Defrost thermostat defective or loose 
 
(Sec. 2.0 and 4.7).
3.  Loose connection in compressor circuit 
 
(see Fig. 3).
4.  Defective compressor overload (Sec. 4.6A).
5.  Defective compressor (Sec. 4.6).
6.  Defective relay (Sec. 4.9).
7.  Defective time delay (Sec. 4.0).
No dehumidification. Blower runs but compressor does not. 
Pump fail light not lit.
.  Bad connection in compressor circuit (Fig. 3).
2.  Defective compressor capacitor (Sec. 4.6A).
3.  Defective compressor overload (Sec. 4.6A).
4.  Defective compressor (Sec. 4.6).
5.  Defective relay (Sec. 4.9).
6.  Defective time delay (Sec. 4.0).
No dehumidification. Pump Fail Light lit. Blower runs but 
not compressor.
.  Bad connection in pump circuit (Fig. 3).
2.  Pump float switch or safety switch defective (Sec. 4.8).
3.  Pump motor defective (Sec. 4.8).
Blower does not run. Compressor runs briefly but cycles on 
and off.
.  Loose connection in blower circuit (Fig. 3).
2.  Obstruction prevents impeller rotation.
3.  Defective blower (Sec. 4.5).
Unit removes some water but not as much as expected.
.  Air temperature and/or humidity have dropped.
2.  Humidity meter and/or thermometer used are out of 
calibration.
3.  Unit has entered defrost cycle (Sec. 2.0 and 4.7).
4.  Air filter dirty (Sec. 3.).
5.  Defrost timer incorrectly set for conditions (Sec. 2.0 
and 4.7).
6.  Defective defrost thermostat (Sec. 4.7)
7.  Low refrigerant charge (Sec. 4.4).
8.  Air leak such as loose cover.
9.  Defective compressor (Sec. 4.6).
0. Restrictive exhaust ducting (Sec. 2.5)
Unit runs but does not pump water.
.  Hose kinked or plugged.
2.  Pump check valve plugged (Sec. 4.8).
3.  Bad connection in pump circuit (Fig. 3).
4.  Hose disconnected internally.
Unit pumps water automatically but not when purge switch 
is pushed.
.  Bad connection in purge switch circuit (Fig. 3).
2.  Defective purge switch (Sec. 2.7).
Figure 2: Refrigeration system of Phoenix