Why is my a/c unit a giant ice cube?

[ihateimacs]

I know this is way off topic but I didn't see any other places to post this and this is the first forum to come to mind lol.

So I noticed it was a little bit warm in the house yesterday and today and decided to figure out why. I noticed the air handler was leaking water from the drain into the garage I got up onto the ladder and took the cover off and saw that almost the entire unit is frozen solid. The unit itself is in the garage which is a good thing so its not leaking into the house through the ceiling.

Here's a pic of the unit with the cover off:

The yellow stuff you see is fiberglass from the cover.

And here is a pic of the coils:

Sorry if I name parts wrong I just bought the house about 4 months ago as my first and am pretty young. I have been browsing on here for a long time, quite a bit before I signed up. Hopefully I will be able to provide inspiration as you guys have done for me!

So any idea why/how this happened? I know cars have an evap temp sensor to keep this from happening. I have had the cover off a couple of other times and everything was clear, other than some dirt and stuff. I was given a can of cleaner specifically for cleaning the coils and used it a couple months ago.

Any Ideas? Thanks, Tommy

Here's the garage to keep this sort of related to a garage forum lol I have a long way to go! This is half of the 2-ish car garage I am building a turbo mustang on the other side.

 

[930dreamer]

My answer is a little OT also. We had this problem in our fleet vehicles when the intake was block, anything blocking airflow?


http://www.hvacpartsoutlet.com/troubleshootafrozenevaporatoraccoil.aspx

 

[east_tn_emc]

Most likely low on refrigerant gas. Call the AC repair person.

 

[east_tn_emc]

And go ahead and cut OFF the A/C ASAP to prevent compressor damage.

 

[Ric in Richmond]

dirty filters/ low freon....

 

[Kinger]

And go ahead and cut OFF the A/C ASAP to prevent compressor damage.

dirty filters/ low freon....

Do these before calling a repair person. Turn off the AC but leave the fan on "On". Change your filter. Most likely it is completely clogged.

 

[Bronson]

Do these before calling a repair person. Turn off the AC but leave the fan on "On". Change your filter. Most likely it is completely clogged.

Yes, defrost it before the repair guy gets there, He can do hid job much quicker if it is not frozen up. At thermostat, turn AC OFF, Fan ON to defrost.It will take a while.

 

[phbsales]

Dirty filters and low refrigerant charge are the most common reasons why evaporator coils ice up.

+1 on getting your favorite HVAC technician out to solve your problem.

 

[ihateimacs]

Do these before calling a repair person. Turn off the AC but leave the fan on "On". Change your filter. Most likely it is completely clogged.

I turned it off right away to start defrosting it. I replaced the filters about 3 months ago with the fancy ones that claim to stop allergens and all that other marketing stuff lol I will have to bring the ladder inside to check them. I have a really good friend that owns a fairly large a/c company that helped me get the a/c working in the first place which is why I got the house so cheap. Thanks so much for all of your replys!

 

[W_A_Watson_II]

The fancy ones tend to reduce air flow, and could contribute to a low freon issue. When the high efficiency filters first came out the better HVAC guys were changing from a 1" thick filter media to a 2 or 3" to increase the filter cross section and not drop the air flow as much. However the Lowes/WalMarts never picked up on the thicker filters, and home owners didn't want to pay to have some duct work changed, so we have what we do now.

 

[ihateimacs]

I figured they would reduce airflow when I bought them but my wife has terrible allergy problems so I did it for her. Makes sense about the thicker filters. I pulled mine down to look at them and they were pretty filthy. I think I am going to try out some not as efficient ones. I also noticed on the page that you shouldn't keep vents closed and I know there are a few closed in some rooms were no using so I will open em up! Thanks again for all the contributions!

 

[HVAC Phil]

Fancy filters ****. Toss them. Most likely the duct work isn't able to accomodate the restricted filter. 3 months on those garbage filters is way too long.

 

[sdowney717]

can also be a dirty coil. Once my coil had a layer of what looked like felt paper against the cooling fins.
Froze up the coil and very little air flow.

I peeled it off and it came off like a sheet of felt.

 

[rickairmedic]

I figured they would reduce airflow when I bought them but my wife has terrible allergy problems so I did it for her. Makes sense about the thicker filters. I pulled mine down to look at them and they were pretty filthy. I think I am going to try out some not as efficient ones. I also noticed on the page that you shouldn't keep vents closed and I know there are a few closed in some rooms were no using so I will open em up! Thanks again for all the contributions!

The filters I use in my system are the pleated ones you can get at Lowes 3 in a pack for $6.50-$7.50 . The 3M ones will piss off most AC systems . Also dont buy the lasts 3 months BS . Change them once a month at $2.50 a piece they are cheap .I will add if your wife has allergies that bad talk to your AC buddy about a " good " uv light system for your HVAC system .


Rick

 

[RobertMo1988]

its recommended to change them every 30 days on most filters, even with pleated filters i change mine every month. what does the condenser coil(outdoor) look like?

 

[ihateimacs]

its recommended to change them every 30 days on most filters, even with pleated filters i change mine every month. what does the condenser coil(outdoor) look like?

coils are a little dirty, but not that bad. I ended up calling my a/c guy and he said the exact same thing all you guys did lol

I bought some cheaper filters with a lot less pleats and plan on changing them more frequently.

As far as allergies I'm not sure how bad hers are as I have no issues with them, but I know she complains about them. She doesn't see a doctor regularly like some people I know to get shots but she has medicine that she takes. I will mention the UV light to him though I have been hearing good things about them.

Thanks again for all of the replys!

 

[rickairmedic]

its recommended to change them every 30 days on most filters, even with pleated filters i change mine every month. what does the condenser coil(outdoor) look like?

Actually alot of the 3M filters say good for " up to 90 days " on them . I guess its supposed to make you feel better about spending $13.00+ on a filter .


Rick

 

[phbsales]

I have lived in my house for 10 years. I have changed my 5" pleated filter media exactly five times and never had my "A" coil freeze. "How can this be?", you may ask. Simple. I have a magnahelic pressure gauge on the return and another one just above the evaporator. I change my filter based on the pressure drop across the system.

Granted, 90% of the HVAC systems out there are not designed like mine is, but my whole point of this post is to dispel the fact that standard systems don't play nice with high efficiency filters.

On standard market systems, the filter needs to be changed every 30 days. Oh, and clean the house more often....run the sweeper for Pete's sake.

 

[csp]

Granted, 90% of the HVAC systems out there are not designed like mine is, but my whole point of this post is to dispel the fact that standard systems don't play nice with high efficiency filters.

Hell, I would guess that most "standard" systems aren't designed whatsoever. Trunks and ducts are placed where they will fit and where most cost effective to the tract home builder while meeting minimum code.

Those 5" filters are great. We have an Air Bear setup in our home.

 

[Milton Shaw]

Your wife might try a HEPA filter in the bedroom at night and keep the door closed. Its made a big difference in my nightime allergy problems. Also makes a "white" noise that lets me sleep even if the washer is running. I got a Shop Fox Shop HEPA filter that I used in my bedroom. Its filters better and the filters are cheaper than some actually make for inside the house. Every body else's post on freon level, pleated filters, and closed air vents, dirty evaporator are correct in that all of them will cause freezing coil. Make sure you save a picture of the frozen coil for the HVAC repairman so he can see what its doing. I hated going into houses on repairs when someone had fixed the symptom (frozen coil, frozen icemaker, frost in freezer, etc ) and not been able to show me what was wrong, it adds questions to what the repairman has to do

 

[fasteddie24]

A buddy of mine just had the same problem and didn't know what it was. Fortunately, his hvac guy is a friend and called him to let him know that there was a recall on some part. Came out, replaced it, good to go. I wish I had more specific information, but the block of ice issue is what caught my attention. Good luck either way.