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2002 444 aft a/c shutting off- HPF code on thermostat
Posted: November 2nd, 2020, 7:53 pm
by 813rob
I can cut breaker off, then back on. It will run for hours sometimes, then same thing, cuts off, HPF code comes on the thermostat. Any help appreciated.
Re: 2002 444 aft a/c shutting off- HPF code on thermostat
Posted: November 2nd, 2020, 11:41 pm
by g36
If you'll search hpf on this forum you'll get alot of info on others who have had this issue.
Re: 2002 444 aft a/c shutting off- HPF code on thermostat
Posted: November 3rd, 2020, 11:50 am
by km1125
HPF usually means "High Pressure Fault", and is usually because of insufficient flow of water though the system. Either there is blockage in the intake, strainer or heat exchanger. Start with the easiest first... the strainer.
You should also check the airflow and make sure there isn't a lot of lint or dust built up on a screen, filter, or the fins.
Re: 2002 444 aft a/c shutting off- HPF code on thermostat
Posted: November 3rd, 2020, 1:52 pm
by Cooler
Yep, check to make sure you have a lot of airflow around the unit. Are you getting a good stream of water output? I had an error code of CLF, and it came down to dirty air filter, a square piece of webbing that had some lint/dust in it. I also had a bag of rags near the unit in a storage cavity. Lesson learned....keep area open near unit. Mine is original 95 Marineaire, 16K.

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Re: 2002 444 aft a/c shutting off- HPF code on thermostat
Posted: November 3rd, 2020, 7:09 pm
by tomschauer
HPF is high pressure fault as mentioned. If it fails in the cooling mode, you don't have enough water flowing or your water to water heat exchanger is fouled.
If it failing in the heat mode, you are not moving enough air. Dirty filters, dirty coil or blocked vents.