A few a/c ??s

[Andy Jarchow]

Two a/c questions:

What realistic things can damage a/c equipment if the wrong size breaker is installed (30a on a 25a max)? Don’t the a/c units have internal protection (is this a big deal)?
I call this out every time I see it but if it’s the only thing I find I don’t recommend an electrician just for this. What do you hi do?

I’m told the newer ac units keep the coolant at the right temp. If this is true at what temperature is it safe to test the unit (still 60 – 65) or does this change for newer units?


Say at the time you started your inspection it was 58 degrees. By the time you finish it is 68. Would you test the unit before leaving?

Thank you all for your willingness to share your knowledge and experience!
Have a great day! :)

[Michael Thomas]

A while back got a call for a seller after I had "broken" their AC during testing.

When the HVAC tech came out he found the condenser full of lint from a nearby dryer vent (in the report, of course):

"Don't you remember that I had to come out for the same problem LAST summer?

I don't not know about damaging the AC, but I'm pretty sure that it will damage my bank account if a compressor fails after and inspection and I've failed to report a OCPD/condenser mismatch or run it below 65F for 24 hrs.

[Scott Patterson]

Two a/c questions:

What realistic things can damage a/c equipment if the wrong size breaker is installed (30a on a 25a max)? Don’t the a/c units have internal protection (is this a big deal)?
I call this out every time I see it but if it’s the only thing I find I don’t recommend an electrician just for this. What do you hi do?

If the data plate says it needs to be 35amps and they have a 40amp or anything higher than what is listed, I call it out. Chances of anything happening are slim, but it that it what the manufacturer wants we do not have much of an option. It will or could void the warranty.



I’m told the newer ac units keep the coolant at the right temp. If this is true at what temperature is it safe to test the unit (still 60 – 65) or does this change for newer units?


Say at the time you started your inspection it was 58 degrees. By the time you finish it is 68. Would you test the unit before leaving?

Thank you all for your willingness to share your knowledge and experience!
Have a great day! :)

I still go with the 60f to 65f degree range. With a Scroll compressor you are not going to hurt anything even with temps down in the 40's.

[mike huntzinger]

you can walk into any Denny's Dinner in the middle of winter and they always have the ac going, I have been told that customers eat more that way

[David Bell]

I came accros a 2.5 ton compressor the other day that was tripping the breacker periodically. I reset the 30 amp breacker and performed an amp test for 15 minutes to see what the draw was. I never saw the draw climb above 13.7 on either leg in that fifteen minutes. Assuming I had a weak breaker I replaced it with a new one and went on my way. Phone rang the next morning and the breacker had tripped. Turns out that the compressor would run fine for 45 min. or so until it overheated and tripped the breaker. A compressor change was the repair. The point I am trying to make here is if the breaker size was increased it may have masked the problem and created a more dangrous situation. As for tempurature ranges, look for a crankcase heater and other low ambient controls before starting any hermetic units below 60. Scrolls are less likely to be damaged but make a scary noise when slugging liquid.

[Andy Jarchow]

I came accros a 2.5 ton compressor the other day that was tripping the breacker periodically. I reset the 30 amp breacker and performed an amp test for 15 minutes to see what the draw was. I never saw the draw climb above 13.7 on either leg in that fifteen minutes. Assuming I had a weak breaker I replaced it with a new one and went on my way. Phone rang the next morning and the breacker had tripped. Turns out that the compressor would run fine for 45 min. or so until it overheated and tripped the breaker. A compressor change was the repair. The point I am trying to make here is if the breaker size was increased it may have masked the problem and created a more dangrous situation. As for tempurature ranges, look for a crankcase heater and other low ambient controls before starting any hermetic units below 60. Scrolls are less likely to be damaged but make a scary noise when slugging liquid.

Thank you all. :)

I will stick to not tested due to outside temp.