SRC Service Manual
Revision 02
Aug 2007
3) The dewpoint temperature sensor (B1) is out of calibration, causing a high reading.
This can be confirmed by using a temperature gun to check the temperature at the
location of the dew point probe, and comparing it to what the probe is reading.
Remedy – Replace the defective component.
4) The coolant pump is not coming on, and therefore not circulating coolant through
the air-to-coolant heat exchanger. There is no cooling of the air. Can be confirmed
by checking the coolant pump. It should be on at all times when the dryer is on.
Remedy - Replace the detective component.
5) A low refrigerant charge is keeping the coolant - and therefore the air - from being
adequately cooled.
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.
6) Scroll compressor is rotating backwards because the phases are inverted. In this
case the compressor does not compress the refrigerant so there is no cooling of the
coolant or of the air.
Remedy - Swap two phases on the power supply.
To Reset:
Alarm will reset automatically when the dewpoint goes at least 2
o
C below the High
Dewpoint Alarm Setting (A6). Warning Light goes off, power is restored to the alarm
contacts and “Hd” disappears from the display.
Notes:
This warning is on a 15 minute delay at startup to allow the dryer to get down to
operating temperature without triggering a false alarm.
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