SRL Service Manual 
Revision 00 
July 2007 
 
Page 42 of 56 
 
 
10.2.4 High (Discharge) temperature (Alarm) 
 
What it means:  Temperature sensor B3 (compressor discharge temperature) registers a 
temperature above  248
o
F (120
o
C). 
What it does:  Cuts power to compressor contactor & alarm contacts. Turns dryer OFF. Turns on 
Warning Light & blinks “Ht” on the digital display. 
Possible Causes & Remedies:  
1) A low refrigerant charge is causing the refrigerant to absorb too much heat in the 
evaporator causing a compressor discharge temperature in excess of 248
o
F. 
Remedy – Check or leaks at welds, threaded connections, schrader valve caps, 
and joints of the condenser and evaporator. Repair the leak, pull the system to deep 
vacuum and charge the dryer with the correct amount of refrigerant as specified in 
the Section 2.3. 
2) A clogged refrigerant filter is restricting the amount of refrigerant getting to the 
evaporator, causing it to absorb too much heat, which causes a compressor 
discharge temperature in excess of 248
o
F.  This can be confirmed by measuring the 
temperature drop across the filter, which should not exceed a few degrees. 
  Remedy – Replace the clogged component. 
3) A clogged capillary tube is restricting the amount of refrigerant getting to the 
evaporator, causing it to absorb too much heat, which causes a compressor 
discharge temperature in excess of 248
o
F. 
  Remedy – Replace the clogged component.  Pay attention when welding the tube, 
not to restrict it or block it with the brazing alloy. 
To Reset:  Find the cause of the alarm and fix the problem. 
Press ALARM RESET to clear alarm. Power restored to alarm relay, Warning Light 
goes off.  Dryer remains OFF.  Display clears. 
  Press ON/OFF to restart dryer. 
Notes:  Alarm can only be cleared if the discharge temperature is below 248
o
F (120
o
C).