Heat Pumps and Electric Heating - checking freon during the winter

How do you check the pressures when its colder out (say 45 to 55)?

Do you put it on heat or cool? and what pressures should I be looking for? this is on an older (say '90) carrier heat pump

The Installation manual will show you graphs with Pressures and Temperatures expected under different outdoor (and indoor) conditions. Graphs show both, heating-mode and cooling-mode performance which will allow you to know if the unit has the proper refrigerant charge.

At outdoor temperatures 55F or below you've got to have the unit on the heating mode for sure.

how do you do it if the unit is so old that you dont have and cabt get the installation manual?

Is there a generic chart for r-22 systems that I could use?

You should call some one out to do this.. You need to be certified by the EPA to do this.

:rolleyes:

come on now. I do everything myself and proud of it. I am even mvac certified. I guess i could look elsewhere. I understand how ac and heat pump systems work- its not rocket science. I was really just wanting to check the pressures and see if they were up to snuff. if it were a car, i'd be set. but geez, I cant check my own home

my friend checks their rental properties pressures in the summer and has given me a vague idea of what to look for there but I figured the winter checks would be somewhat different. as for the EPA, there isnt anything dangerous environmentally unsafe about hooking up a set of guages and reading pressures. its done one way you could only screw it up if you were a moron (and youd see the errors of your ways pretty darn quick when your low side pegged out). but the thats another rant for another day.

btw, isnt it GREAT how the feds can get their noses in our business and control us like we're morons- all for our safety. Thanks for caring. (I actually found a few good sites after posting- such as http:/ and others.....)

Heat pump is a diffrent breed of system.. It's not your standard A/C.

Charging these can be tricky, and you think you got it right, then come summer you find out the system is over charged, and you now have to remove the charge.

Sorry, I don't made the laws on the EPA.

but the EPA laws don't prevent you from explaining how its done, do they? and I see the laws prevent a person from 'checking' the pressures, (so I can understand you concern). nonetheless, ive got it covered- legally.

Sorry we can't help but we here at Doityourself can not give step by steps on performing an illegal act.

no problem. I figured I'd ask anyways.

when i get some time, I will work on getting my 608 cert. Why not, right?