home central AC froze up- help

rfuerst911sc · 08-04-2006, 03:32 AM

Well this morning for the 2nd time in 2 months my home central AC evaporator froze up solid. I know it has a leak but was hoping to limp it to the fall but I guess not. The system is a Rheem and is about 13 years old. To my knowledge the outside unit ( condensor ? ) is still good but would you guys replace everything and be done with it? I plan on living in the house for at least 7-10 years and AC in Orlando is a must. Any advice is appreciated in regards to brand,refrigerant,SEER rating I should go with etc. The house is 1880 s.f. and was built 13 years ago. Thanks.

ejames19 · 08-04-2006, 04:06 AM

You probably have already done this but, this happened to my neighbour twice this summer and I told them to check their filter. 'What filter?' You wouldn't believe the amount of dust build up, about an inch thick. Turned off AC for about 4-5hrs with just the fan running to let it melt, new filter running great for over a month, and it has been hot up here for the past month. Just thought I would give my 2 cents. Good luck.

Kirk911SC · 08-04-2006, 04:10 AM

Sounds like you are low on refrigerant again. Filter check is good advice.

What do you have the thermostat set to?

Kirk

turbo6bar · 08-04-2006, 04:45 AM

Gosh, that's a lot of freon to lose in 2 months. The leak must be quite large. I'd get a pro to do a leak check and go from there.

As far as getting the unit replaced, I'd go with R-22, any brand (installer is more important), and SEER 13, because that's the lowest rating you can get. You'll pay a good premium for the higher SEER rating equipment and Puron refrigerant requires more installation time, so the final price is higher. You can do a cost analysis, but at this point I do not feel the high efficiency units are cost effective. Spend the bucks on better attic insulation.

Jims5543 · 08-04-2006, 05:22 AM

Do you know anyone in the A/C business that can get you a hook up?

I have a couple of friends that own shops here and you would be amazed at the markup on the units. Like 300%.

I payed $900 for a SEER 12, 2.5 ton system about 7 years ago. The street price for the rig was close to $5000.

masraum · 08-04-2006, 05:32 AM

A couple of years back I got a 3 ton (or was it 3.5) for $1000. It was a local company, but has a 10 year warranty. The old guy that installed it is the guy that installed the last one in our house many years before we moved into it.

rfuerst911sc · 08-04-2006, 05:51 AM

I check and clean the filter about every 2 months as a matter of fact I cleaned the filter yesterday. I normally keep the AC set at 76-78 degrees. I know the evaporator has a leak because I had it "sniffed" a few years ago and they said that's where the leak is. If I replace it I will go with a 13-14 SEER the one I have now is 10. I have a Trane dealer coming around noon to give me an estimate. I just got back from a 2 week vacation and now we jump back to reality real quick! I like the idea of staying with R22 as I have heard Puron may not be the accepted standard for the future. I believe the unit I currently have is a 3.5 ton.

onewhippedpuppy · 08-04-2006, 06:13 AM

If it's just an evaporator it shouldn't be a huge expense, and a 13 year old condenser unit should have a lot of life left in it. Unless your old system is inefficient and you want to upgrade, I would just fix it.

Kirk911SC · 08-04-2006, 06:21 AM

If you upgrade to Puron (R-410A) with a higher SEER unit you may need to change the evaporator and/or expansion valve due to higher pressures with that type of refrigerant.

914GT · 08-04-2006, 06:34 AM

On some Rheem units, check the fiberglass insulation pads on the sides of the blower housing. After a few years the contact cement holding these pads can fail, and they get sucked up against the blower inlet blocking off the airflow. With insufficient airflow the evaporator freezes-up. Since the insulation falls back into its normal position with the blower off this is an easy thing to miss during inspection.

einreb · 08-04-2006, 07:02 AM

Quote:

Originally posted by rfuerst911sc
I check and clean the filter about every 2 months as a matter of fact I cleaned the filter yesterday. I normally keep the AC set at 76-78 degrees. I know the evaporator has a leak because I had it "sniffed" a few years ago and they said that's where the leak is. If I replace it I will go with a 13-14 SEER the one I have now is 10. I have a Trane dealer coming around noon to give me an estimate. I just got back from a 2 week vacation and now we jump back to reality real quick! I like the idea of staying with R22 as I have heard Puron may not be the accepted standard for the future. I believe the unit I currently have is a 3.5 ton.

the other oddball thing that can cause a 'low flow' situation is a bad control board. the heat mode typically has a lower fan setting than cool. We had a unit where the control board went bad and the fan was in a low speed setting in the a/c mode and freezing up the coil.

I jumpered the fan relay to get it to run all the time at a high speed setting until the new board arrived.

mtelliott · 08-04-2006, 07:16 AM

One of the simple solutions is to put the fan on constant on instead of auto. That way, the fan is constantly circulating air across the coil. I did this and haven't had a problem since.

The best advice is clean the filter. 13 years isn't old and shouldn't be the problem. Mine is 20+ and still kicking.

Rikao4 · 08-04-2006, 07:55 AM

All what they said, for me it was a dirty coil..b*tch to get at, as they installed the unit first, and THEN build the walls around it .
Rika

R Wilco · 08:38 AM

Geez. Hold up. If you'll pull the panel off that exposes the coil, sometimes when it freezes up it attracts dirt, sludge, mold whatever. Get you a couple of cans of brake cleaner and blast that crap out of it there. My neighbor has a system that is 50 years old, mine is 30, I have to do this every couple of years because the filters let stuff through.The systems are closed, you shouldn't have leaks unless something is rubbing on something creating a hole in a hose etc.

turbo6bar · 08-04-2006, 08:42 AM

If your evaporator coil isn't a crazy design, you can get them for around $300-500 + labor. That would get you back in business, and you would know the coil is clean.

If you have a closet AC unit, the evaporator coil can get dirty very easily. That will definitely lead to the system freezing. However, if you know you have a leak, that'd be the first problem to address.

rfuerst911sc · 08-04-2006, 10:38 AM

Well the AC dude just came and we agreed on a price, all new Rheem 13 SEER 3.5 ton with some 10 inch thick super filter,install with new 60feet of copper line,variable speed fan with a 10 year extended warranty that covers everything including lightening damage,digital thermostat,maint. kit which includes tablets for the drain line to kill mold buildup and a cleaning of existing ducts for $5300.00 total.It will all be installed tomorrow. I have a neighbor that just had a 3 ton unit and they were charged $7000.00 with no extended warranty or the super filter so I think I did O.K. The joys of home ownership!!!!

Keith Perry · 08-06-2006, 07:14 AM

Sheesh! I had the blower die on my 35 year old 3 ton and managed to cram in a junkyard 5 ton 5 speed blower, because that's all I could get my hands on for free. On the highest speed it cools the house in minutes and blows hard from the furthest vent. And my utility bill dropped by a third. Of course my Buddy who actually knows something and adjusted the charge to the system, says it'll be dead in 5 years, but here on St. Helena, that's better than the $7,200.00 I was quoted to "DO IT RIGHT". Now pass me back my beer.