HVAC pressure switch

Mine just went out last month.

Just had mine replaced in one of our units, $225 for call out and part.

Heat Pump (you say one doesn’t heat)? “Average” life expectancy of a HVAC is considered to be 13-15 years in the Deep South - so sounds as though you’ve gotten you $ out of the unit.

Not all HVAC condensing units have low limit and high limit pressure switches, lower end models often don’t, and the switches help to protect the compressor and coils. If it’s been professionally diagnosed, have the switch replaced - you may have several more years life in that unit. As stated, it shouldn’t be an exceptionally high expense.

Other things to look at? Eventually something major will fail - compressor, coils may leak at which point the cost to repair will likely lead you to replacing the units because of their age - in the meantime just maintain them annually by cleaning the coils, replacing filters, etc.

If a HVAC tech does this for you, they’ll typically check amp draw on major electrical components like the compressor, condensing unit fan motor, air handler/furnace blower motor, refrigerant pressures, superheat, subcool, which can provide some indication that one of those components may be failing or there maybe a leak in system, or some another impending issue. Always great if they can measure total external static pressure (TESP) but probably none do that even though it takes all of 10 minutes.

Call Matty Ott for all of your HVAC needs 504-913-3688

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pressure switches dont hardly ever go bad, they either work or they dont, but when they go bad then it wont let the compressor run to allow it to cool.

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On one unit, I did have a bad pressure switch. He replaced it. The unit now works without any issues.

My other unit was out as well. Wouldn't heat either. This wasn't a bad pressure switch. Apparently, I had 6 bird nests that came through the roof vent (and built on top of one another), and one even made a nest in my HVAC blower motor. The service technician cleaned it out for me, and fired it up. Works perfectly.

I'm working to figure out how to prevent this from happening again.

Also, the service technician said both of my units are in great condition, and it was his recommendation to keep running them. He said the newer units might be more efficient, but they aren't built like the ones I have. He said I should save my money.

I've only used one company the entire time I have been living in my house (15 + years). The same service technician is still there and always services my house.

quote:

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On one unit, I did have a bad pressure switch. He replaced it. The unit now works without any issues.

My other unit was out as well. Wouldn't heat either. This wasn't a bad pressure switch. Apparently, I had 6 bird nests that came through the roof vent (and built on top of one another), and one even made a nest in my HVAC blower motor. The service technician cleaned it out for me, and fired it up. Works perfectly.

I'm working to figure out how to prevent this from happening again.

Also, the service technician said both of my units are in great condition, and it was his recommendation to keep running them. He said the newer units might be more efficient, but they aren't built like the ones I have. He said I should save my money.

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i never in my life heard of a way birds could get into your blower motor. unless you are talking about the gas heater vent pipe blower. i have seen those get jammed with big wasp nests before. do you have gas backup heat for your heat pump?

as to a possible issue - there is a circuit board that runs the outside unit and that could be the issue not telling it to cycle into heat

any way, the guy is saying the right things so stick with his best judgement. if he wanted to rip you off, he would have been in a hurry to sell you on a new unit, not tell you its not needed.