Testing Heat/AC

Below what temp do you not test AC?

Above what temp do you not test heating systems? Do you make exclusions when the heating system is gas?

Always test the heat cycle, also check electric heating strips on heat pump separately
I test the refrigeration cycle for operation. However it’s where you’re comfortable with
some say anything under 60° we do not test.

Hey Wayne I have never met that some say guy where is he from.

The low temp pretty much a standard 60 degrees don’t operate the conventional A/C.
I am not saying what I do in reference to the 60 degree BS I am not going to start a war of words???

lol I test them to see if they operate. Yes this is been discussed thousand the times. I don’t think he has to worry in Florida

We do get down into the 50s where I am. Currently I’m enrolled in a course where the instructors both do not test AC below 60 and any heat pumps above 80.

Any thoughts on why you would not test heat pumps above 80? Or if you test them regardless of temperature, you never had an issue?

Because your instructor does not know any better. Saying not to operate a heat pump in the heat mode if the outside ambient is above 80 degrees is the same as saying don’t operate the A/C unit if the outside ambient is above 80 they don’t understand the heat pump cycle.

I had the same instructors. They said you could damage the reversing valve.


Yes, I’m in the class now and getting “the gas gets thin” as an answer. I don’t want to break someone’s heating system but I’d like to know if it is true or not. Not testing a heating system seems like a fairly big omissions.

Its not true !!! we operate a heat pump in the cooling mode when its 110 degrees outside ambient that 110 degrees going across the outside condenser does not damage anything they are designed for that type of temp SOOOOOOO why would 80+ degrees outside ambient harm the reversing valve when in the normal heat mode. Your instructor needs to bone up on heat pumps

Look at it this way when in the normal heat mode The outdoor condenser becomes the A-coil just a different shape you have a temp on the outdoor coil @ 38- 42 degrees with a outdoor temp passing across that coil say 90 degrees you get a temp transfer still within design operating temp of the unit.

Still in the normal heat mode hot gas (vapor) enters the indoor A-coil at say 130 to 140 degrees with the temp of the return air within the home ( 70-80) degrees passing across the A-coil with a temp transfer no damage still within design spec of the MFG.

Bottom line is you can not damage these heat pumps by testing in the summer time. You won’t get any significant temp readings but you will be able to determine if the reversing valve does indeed operate and that basically is all a inspector needs to know and that can be determined in less than 30 seconds. If a heat pumps operates normal in the cooling mode it would operate normal in the heat mode all you need to know is does the reversing valve operate ???end of story

My instructor said never test AC below 65 degrees, but make a furnace come on no matter what.

We really didn’t get in heat pumps and boilers, as they are uncommon in Southern California.

We live in Florida and both settings are tested at all times. I’m not wanting to start a debate but I can’t seem to even think that such can be done when the systems are installed by the technician all year round both settings are tested.

If you really wanted to know the answers … WHY would you ask a bunch of us home inspectors, MANY of which don’t know themselves. WHY would you not call the manufacturer; distributor; factory rep; a local AC school instructor, etc and ask them?

Because we love to listen to people that don’t know what is what and make it a fact.

How many years have I said you can’t tell if an HVAC unit is operating with a dry bulb Delta T?!
I go on to prove it.
Still, how many of you test this way?
“Because my Instructor said so…”

I would go on to explain all this, but I’m just a Home Inspector.

So I’ll just stick to my opinion (that everyone hates);“If you don’t know the system you are inspecting, there is no damn good reason for YOU to be inspecting it!”

If you have to ask, why are you doing (or not doing) it?
If you don’t know what will happen when you turn on the heat in the summer, you don’t know what your looking at in the first place. So what are you testing? Do you even know?

If you come here and ask a question, but then argue with Charley, what are you here for?
How many times does he have to argue this point?

You should realize YOU can’t do it all. So instead of blowing smoke up someone’s ***, you hire someone that knows (if that is what your client is wanting and willing to pay for)…

You can turn on any type of heat in the summer, but not for 2 hours (trying to get some Delta-T).

A furnace has a High Temp Safety and a Heat Pump has a High Pressure Safety.
Both shut things off if there is something wrong with the equipment design (or your just being stupid collecting heat temps in the summer).

This reminds me of an AHJ Inspector (who must have gone to some Home Inspector School) who insisted on running a gas furnace for 30 min. on every inspection. I got called in by the installation department because the furnace wouldn’t keep running for the Inspector on this new install inspection (at 100F OA at 5:Beer30pm). They tried to tell him it was just too hot out (and in), but No, some dumbass taught this guy to be a dumbass and would not pass it.

I put in a higher temperature limit switch (till the dumbass left).
Even though this could have damaged the heat exchanger, that’s what it took to appease a misinformed Inspector.

Are you this type of Inspector? Just askin…

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