Central air unit

[Scott K]

My central air unit has been getting a little noisy the past couple years, it works well, but it is noisy. It is an old Rheem unit here is the tag

My buddy has a unit I can buy from him for $100, and he said it works good, but he is replacing it for another unit, her eis the tag from my buddies

It comes with the A coil.

OK, my questions, I think they are both 3 ton, I think my Rheem is a 10 seer, and the Lennox is an 8 seer?? Is it to buy the unit off of my buddy for $100? Will it work? If I did buy it, would I have to replace the A coil? I had a new one put in with a new furnace 5 years ago. Anything else I should know?

[fishersofmen]

It would work fine, no reason to replace the A-coil. One thing to keep in mind though is an 8 seer ac unit is not very efficient so you would be going in the wrong direction as far as efficiency. My heat pump is a 15 seer which would use close to half the consumption of an 8 seer. If it were me I would consider getting something more updated efficiency wise it makes a big difference in the end.

[nobody05]

your rheem is 2.5 ton. that lennox is a 3 ton. therefore you would have to replace your existing a-coil to accommodate the 3 ton unit. Your rheem is an 8 seer the lennox is a 10 seer. Just to warn you it's r-22 a refrigerant that is being phased out. Does the refrigerent come with the unit is the main question. If not its not worth the 100 bucks. Being r-22 is being phased out.

[BartmanMN]

what is noisy on your Rheem? My Rheem was noisy so I took off the cover and sprayed wd40 on the shaft of the fan blade and now it is quiet. There really isn't much to these things.

[fastkaw]

ILL try to make this short...

Don't waste your money.

If your old AC is over 10yr. old, wait for it to die and upgrade to a 14seer. Save your money now and put it into the new.

There are about 20 other thing I could mention why not to do it.

[Scott K]

I passed on buying it, I figured it if I were to replace it, I may as well get a new efficient unit in there.

As for the noise, it has a loud higher pitched buzz coming from it. I havent really looked at what was making the noise. I will take the cover off in the spring and clean it, and check where the noise is coming from then, see if a little lube will quiet it up some. It does work pretty decent, and I havent had to add freon to it. I guess, dont fix what isnt broken.

[Eric Wettschreck]

Scott, there's only a couple moving parts in these units. A fan motor (with fan blades) and a compressor.

Sometimes the fan guard gets loose, starts vibrating, and makes noise. A weak coil on the motor contactor could buzz also.

Pretty simple and easy fixes with the exception of the compressor.