AU_Prospector

My home has 2 HVAC units a large one for the first floor in the crawl and a large one for upstairs in the attic. My problem is with the larger one.

I turned it on yesterday and noticed it didnt seem to be cooling very well. I went outside and the cold line was only cool while the cold line on the smaller unit was cold in comparison. I let both run for a couple of hours. The smaller unit worked fine, but the larger unit froze up and stopped working.

What I noticed. . .

The cold line was only cool to the touch and only a few degrees cooler than the hot line in comparison to my other unit where the difference was very pronounced.

The unit as a heat pump worked okay during the winter though many times I felt it wasnt warming enough.

The unit froze up after about 90 minutes of continuous operation and the blower switched to a very slow speed.

The air filter is new.

This also happened a few times last summer and fall, but I attributed it to a dirty filter.

Is it time to call for maintenance? I thought these things were maintenance free?

Thanks!
Prospector

kok328

Here's a few reasons why your system would ice up; from there you can decide as to whether you need to call for maintenance.

Air flow issues of any kind (Dirty air filter, Dirty evap coils, Dirty condensor coils, Condensor coil fan motor problems (intermittent, permanent, fan blade damage or speed issues). Evap coil fan motor issues (same as condensor also on belt driven, loose/bad belt)).

clogged/bad filter/dryer, low freon charge, a welded condensor contactor and possibly a bad reversing valve.

Good Luck.

AU_Prospector

$143.00 paid

Tech came out today. Low freon charge. System holds 159 ounces. He put in 34 ounces. He also noticed the factory plastic caps for the high and low pressure lines were missing and replaced with brass caps. This leads him to believe the unit had freon added to it previously.

Going to see how long this lasts. His 'estimate' is there is a freon leak on the low pressure side probably in the evap coils. To replace the evap coils would be an approximately 1200-1500 dollar job. An electronic leak check is $95 which I declined for now.

kok328

Hey, thanks for posting a follow up. Too often we never hear back and it really doesn't add to the value of the knowledge base on this website.
Not a bad price either. Too bad it was among the list of things that you couldn't check on your own. Too often service people are hesitant to repair a leak instead of replacing the coils. Sometimes this is a good idea and sometimes not but, in my book you at least have to try the cheaper route first, even it is against recommendations. I don't think $95 for a few minutes of leak check is worth it, unless you were going to have it repaired. I also don't think that they should charge for that service either but, oh well.

Good Luck, hope the charge last a long time.