Why did whole-house ac stop working, still blowing but not cold?

The air conditioning worked fine then suddenly yesterday it stopped being cold, but fan still works.

Answered! View the answer I have this problem too

Is this a good question?

Score 2

Comments:

@jlozier when you say the fan works you are talking about the outside unit? Can you hear your compressor kick in? When you touch the lines coming out of the cormpressor, are they cold/cool/hot? What make and model is your AC?

by

If this is a home refrigerated air unit, go outside and look at the pipes going into the exchange unit and see if they are frosted over or even have ice on them. Is that fan running?

by

Here is more information, thanks for comments.

While copying the numbers, the unit attempted to start, twice, but went off in a second or two.

I think this indicates that the thermostat is calling for AC but the compressor can/t doesn't deliver.

Is a freon recharge in order? This is something I've never done, but there are access caps on the pipes that go into the house.

The unit is Lennox M/N H529-024-5P, S/N 5805J11611.

by

@jlozier you said " the unit attempted to start, twice, but went off in a second or two." Does it no longer come on? Does the main fan turn? Right now it does not sound like Freon issues at all. Sounds more like the start capacitors etc. You got a multimeter? BTW those things pack a punch, so you want to be careful around the electrical connectors etc. check your model number once more. Is it possible that yours is a Hs29-024 instead of H529? Post some images of your wiring and the capacitors (large round cannisters:-) with your question. There are multiple ways this may have been wired up. Don't touch anything and consider turning the breaker off. Remember that capacitors hold a charge long after you turn the power off, so do not touch anything,yet. Use this guide Adding images to an existing question for that.

by

You need to take a amp draw to see if the compressor is trying to start. It might be drawing locked rotor and kicking off on the thermal overload.

by

Add a comment
Deck the Halls
With tools and Fix Kits

2 Answers

Chosen Solution

@jlozier since this sounds more like a power issue, I would suggest that you check the power to your AC unit first. It should be 240V (depending where in the world you are:-) If you have power to the AC then you want to check the run capacitor. It is in charge of the fan motor and the compressor. Check it for bulging, leaking and/or severe corrosion. If so replace it. The next part on my checklist is the contactor. That is basically a 24V relay that closes the circuit when your thermostat calls for cooling. There are a few different ones for your AC model, which makes it somewhat important that you post some pictures with your question. Use this guide for that since it will allow us to see what you see. Please remember that the voltage and amperage on your AC packs a heavy punch. Do not touch any live wires etc.

BTW you and I will not beable to purchase any refrigerant since that requires a HVAC license and some nifty gauges to refill the unit.

Block Image

Was this answer helpful?

Score 2

Comments:

Thanks, oldturkey and others, this is beyond me, I'm going to call a professional.

by

Add a comment

It's easy , the freon is in really low value.

https://simple.wikipedia.org/wiki/Freon

Just replace it by adding more "gas".

Was this answer helpful?

Score 0
Add a comment

Add your answer

John Lozier will be eternally grateful.
View Statistics:

Past 24 Hours: 0

Past 7 Days: 3

Past 30 Days: 6

All Time: 228