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Heat pump discharge over temperature

System locks out and indicates that the temperatue of the discharge line from the compressor is at to high a temperature. What could be causing this problem?

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  • rt89 Feb 04, 2009

    filter etc; is clean no AIR FLOW restriction. Do you think over charging the system could cause over heating of the compressor discharge?

  • Perry Putnam
    Perry Putnam May 11, 2010

    How does your filter look? Low airflow across the indoor coil in heat mode could raise the discharge pressure and temp. Let me know.

  • Anonymous Mar 19, 2014

    its alarms high discharge temperature what is the posible cause and what is the solution sir? thanks


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  • Master
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Have you changed out the filter on the inside unit lately? remember that is the condenser in the heating mode.

Posted on Feb 01, 2009

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Many times this unit seems like it is running just fine, but in fact it has a problem...
Most have a freeze sensor that will shut down the unit if the evaporator coil gets too cold...
Now that problem can be caused by a couple of things...

A dirty filter or evaporator coil...
Low freon this case you have a leak somewhere in the refrigeration system...
Freeze sensor thermistor (probe) or circuit board are bad....
Fan motor not running full speed.....

These are the most common reasons why your A/C would run for a few minutes and then shut down...


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