My home AC quit cooling, here is what is going on. The A frame coils are icing up after a a couple hours of run time. What  I have done so far is, 1- cleaned drain line it works. 2- blew out A frame with air hose.3- changed filter. 4- checked air intake for blockage. 5- dusted blower off, and it is working ok.

Any advice on what is wrong ?

Have you made certain that the blower is running? If it is, there area couple other things to check. Is the blower motor belt or direct drive?

Let me know, I'll help you through it.

Mike

PS if you wanted we could even do this over the phone and know in about 15 minutes what's going on.

I personaly just went thru this and youve done all you can short of calling in a repair guy. My coils where iced and it ended up being nothing more then a DIRTY air filter.  I spoke to a couple HVAC techs and all of them seemed to come to the same conclusion. With NO airflow over the coils due to the clogged filter, the coils WILL ice up fast, all the way out to the outside unit. MY entire line froze. I shut it down for a night, changed the filter and it has been 2 weeks now and it hasnt reoccured. If the filter was at all blocked it was more then likely your issue. I had no clue they are supposed to be changed every 3 months. Mine had been going for about 7 without a change.........

Quoted: Have you made certain that the blower is running? If it is, there area couple other things to check. Is the blower motor belt or direct drive? Let me know, I'll help you through it. Mike PS if you wanted we could even do this over the phone and know in about 15 minutes what's going on.

Thanks Michael

Direct drive blower, it is running good with normal flow. It just froze up again and shut off air flow, after 2 hrs run time.

Was the filter badly plugged when you pulled it out?

Quoted: Was the filter badly plugged when you pulled it out?

Yes, it was very dirty.

You said it was still frosted, I'm assuming that is still the case. First thing we need to do is get the ice off. If you haven't already turn the A/C off. Do it at the thermostat, and be sure to set your fan switch to "ON" not "AUTO". That can take a couple of hours to thaw. What I would do on a call like this is turn the heat on for 10 minutes or so. Once the ice is off, you may well be good to go.

Mike

My guess is the a-coil is still dirty. But this can also be a symptom of being low on freon.

Quoted: My guess is the a-coil is still dirty. But this can also be a symptom of being low on freon.

Right, but if there is still ice on the coil, that;s just like being dirty.

Quoted: Quoted: My guess is the a-coil is still dirty. But this can also be a symptom of being low on freon. Right, but if there is still ice on the coil, that;s just like being dirty.

You all are very helpful, in thawing mode now, what is the best way to clean the coils ?

Tagged for coolness.

       That can be fairly involved, depends on how much access you have to the inside of the plenum.  I'm going on the assumption that this is a standard upflow furnace in your basement. If you can remove the front of the plenum, or coil cabinet, you can usually remove the end plate on the A-coil.

       At that point, just reach in and brush it off. But be careful, don't bend the fins, and don't cut yourself those fins are SHARP. I have the scars to prove it lol. If you can't access it that way then you will need to try going in from the top. Remove a register if there is one on the plenum, take a run down, or if there is room, cut in a register. Then use compressed air to blow down from the top.

       But most likely your coil won't be plugged, because you did have a filter in there. Even plugged up that would stop most of the crud from reaching the coil.

Mike

Quoted:        That can be fairly involved, depends on how much access you have to the inside of the plenum.  I'm going on the assumption that this is a standard upflow furnace in your basement. If you can remove the front of the plenum, or coil cabinet, you can usually remove the end plate on the A-coil.        At that point, just reach in and brush it off. But be careful, don't bend the fins, and don't cut yourself those fins are SHARP. I have the scars to prove it lol. If you can't access it that way then you will need to try going in from the top. Remove a register if there is one on the plenum, take a run down, or if there is room, cut in a register. Then use compressed air to blow down from the top.        But most likely your coil won't be plugged, because you did have a filter in there. Even plugged up that would stop most of the crud from reaching the coil. Mike

Will check again, and clean if needed.

After checking and thawed it seems like I am getting good air flow through A frame.

If you are getting good airflow, most likely you are good to go. Keep an eye on it for the next couple of days, If it doesn't freeze up again you should be all set. If it does, you may well be into a situation where someone needs to put guages on it.

Mike

Quoted: If you are getting good airflow, most likely you are good to go. Keep an eye on it for the next couple of days, If it doesn't freeze up again you should be all set. If it does, you may well be into a situation where someone needs to put guages on it. Mike

Thanks for your help, will let you know how it works out.

Thanks, I'd like to know. It's always a pleasure to help someone here.

Mike

Well called service, and had it juiced up it was low on freon. It lasted for 2 weeks guess I got a leak, service guy said properly in A-Coil ?