Ten days ago our 11 year old central ac was working fine. Then the outside unit starting making very loud noises. I called a church acquaintance who has his own ac company to come and repair the unit. He said it was the outside fan motor. He replaced that and said he needed to come back the next day to replace the contactor. He didn't have the part with him that day. He came back the next day and replaced the contactor.

Several hours later I noticed that the outside and inside units kept running which is very unusal for my system. Then I checked the thermosat and I noticed it had gotten several degrees warmer all of a sudden. I then went outside and saw that the outside pipe was frozen.

The repair guy had me shut the unit off until he came four hours later. By then everything had defrosted. He said nothing appeared wrong with the unit and when I questioned him about the contactor he said there was no way it could have caused the problem. Even though I told him the unit worked fine for 24 hours after he replaced the fan motor. It only had the problem after he replaced the contactor.

He then told me he thought it was low on freon... so he checked and he said it didn't need very much "only 3 lbs" . So he added freon... charged me $20 a lb for the freon and he charged me for another service call.

Since then system had been working fine for the last week until now. Early today it seemed to me that the unit was constantly running... I should have paid attention then but I didn't until late afternoon. I went to check the thermostat and the temp in the house had gotten quite a bit warmer it went from 77 earlier to 81. I immediately knew this time to go outside and see if the unit had ice... which it did. I shut the ac off and wrote to all of you.

Once again... it's been off long enough to defrost and it is be cooling the air now. After running for awhile air handler temp is now 60 degrees . I understand it needs to be around 20 degrees lower than the warm air temp coming in.

I think you all were on the right track. Several of you suggested there is something wrong with the contactor and it is not shutting off. What else could cause this problem?

Any other suggestions? We am at my wits end and don't feel confident with this repair guy.




:confused: :confused: :confused: One more thing. I've asked several times but haven't gotten any specific answers.

I need help if I have to replace the system. How do I determine if I need to replace the inside coil (condensor?? ) and along with the outside compressor or vice versa?

Also, my system is a 2 and half ton unit and my home is 1560 sq ft. Approx. how much should it cost to replace the system and what brand/s should I consider buying? How does an uneducated consumer determine this? What should I know first before buying and what questions should I ask?

Again, any help that any of you can provide would be really really helpful and truly appreciated.

Thanks,

D

*** Correction to above. The air handler temperature last night was as around 64 degrees (not 60). This morning it is now running around 66 degrees. Outside temp is approx. 80 degrees. Inside house temp is 78 degrees which is where the thermosat is set. I've just lowered it to 75 degrees to see if it gets cooler.

Update. Dave was taken to hospital earlier today so I'm following up for him. I'm his wife and now have to deal with the ac problem along with helping D at the hospital. So any advice anyone can give me is appreciated. I don't know who to trust (repairmen).

Please bear with me on this. What has happened now is the outside unit line has ice on it so I turned the system off. It appears that it runs fine for a few hours and then it freezes. I have no idea what to do or what is causing the problem. The unit is 11 years old and we've been in the house 6 years. There was never a leak and we never needed to have anything repaired on the system until the fan motor. Now everything is gone wrong. The outside lines never froze before this. We think it's all tied together with something this repair guy did, but he says it's just a coincidence. Dave will be in the hospital a long time, and actually may not come home so I have to deal with this myself. I have turned the system off and need to figure out what to do. Once again, any information or advice would mean a world of difference.

Thank you all,
Dave's Wife

Forced air units need lots of air to pass through the acoil if it is dirty the air cannot pass through wich lowers temp in coil to below freezing and that causes the condensation to freez
Check to see if coil is dirty
If coil is OK (not to dirty)
Check air flow (remove air box cover)and tape safety switch to run and see if it freezes