Central air conditioner question/problem

Doggiedog

Lifer
Aug 17, 2000
12,780
5
81
Before I go to a pro, I wanted to run this question by the sages at ATOT.

I just turned on the central AC in the house I just bought. The outdoor unit sounds like a machine gun going off. It is very loud. Any idea what it could be? The AC seems to be in 2 units. The outside AC looks like the back of a normal AC and there is another unit in the attic which I figure is just a fan to circulate the air.

I don't want to get ripped off by the AC guy so I'm wondering what problems it could be and how much it would cost to fix them.

Thanks
 

T3C

Diamond Member
Jun 3, 2003
5,324
0
0
the fan in it is hitting something what i dont know, but you should call a pro on that one!
 

Doggiedog

Lifer
Aug 17, 2000
12,780
5
81
I was think the same thing when I first heard it but the unit doesn't have anything exposed like those circular central ACs I see with the fan on top. Maybe I'll open her up just to check though while the weather is still nice here.
 

Lounatik

Golden Member
Oct 10, 1999
1,845
1
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I used to be an ac repairman in Fla some years back. How old is the unit? It is quite possible that the fan, which hangs from the top, could have broken off of the mounting which could give you the noise, or one of the blades could have broken off from the ring that holds them all together. Do me a favor TURN OFF THE POWER BEFORE YOU DO ANYTHING!!!!!!! ;>) Please do that ! Is the unit cooling at all? I mean, is the unit outside running once it is turned on? If it runs and still makes the noise poke around to see if it is a fan blade(power off of course). If it is a rubber mount or something simple, you probably can replace it yourself. Replacing the blade is a bit tricky, because you need an allen wrench to take the blade off of the motor , but it can be done. Bear in mind that the blade more than likely will be frozen to the shaft and you will have to get some penetrating oil to loosen it up or perhaps a wheel puller. You can do this far cheaper than the 300 or so dollars the repair ding dong will charge you. Dont forget: It is summertime, and they are out to make the most money they can because they know you are up a tree the hotter it gets.

Let me know what you find. And dont forget to turn off the power.



Peace



Lounatik
 

Doggiedog

Lifer
Aug 17, 2000
12,780
5
81
Originally posted by: Lounatik
I used to be an ac repairman in Fla some years back. How old is the unit? It is quite possible that the fan, which hangs from the top, could have broken off of the mounting which could give you the noise, or one of the blades could have broken off from the ring that holds them all together. Do me a favor TURN OFF THE POWER BEFORE YOU DO ANYTHING!!!!!!! ;>) Please do that ! Is the unit cooling at all? I mean, is the unit outside running once it is turned on? If it runs and still makes the noise poke around to see if it is a fan blade(power off of course). If it is a rubber mount or something simple, you probably can replace it yourself. Replacing the blade is a bit tricky, because you need an allen wrench to take the blade off of the motor , but it can be done. Bear in mind that the blade more than likely will be frozen to the shaft and you will have to get some penetrating oil to loosen it up or perhaps a wheel puller. You can do this far cheaper than the 300 or so dollars the repair ding dong will charge you. Dont forget: It is summertime, and they are out to make the most money they can because they know you are up a tree the hotter it gets.

Let me know what you find. And dont forget to turn off the power.




Lounatik


Thanks for the help Lounatik!

I opened the unit up and took a poke inside. It looks like the fan and motor are wobbly. There seems to be a bit of dirt in the motor but to me it looks like the motor is not moving smoothly and is causing the fan to wobble. There is a vertical piece of metal holding the fan and motor in place. It seems like it is not really doing the trick because it is moving somewhat left and right.

It looks like an easy fix but I'm not sure whether the motor needs to be replaced or if I should add some brackets or something to steady the fan. I suspect the AC is about 10-15 years old because that is how old the house is. I added some WD40 to it and the noise went down a little bit but it's still pretty loud.
 

Doggiedog

Lifer
Aug 17, 2000
12,780
5
81
I also forgot to mention, this central AC is not a fan on top AC but a fan on the side like a window AC. It appears to be cooling well but the noise will keep everyone in the neighborhood awake.
 

Lounatik

Golden Member
Oct 10, 1999
1,845
1
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Yeah, you do not want to be running this thing and have the fan crap out on you in the middle of the night. Coz if it does , you could do some serious damage to the whole system. Is the metal bracket replaceable? iIf it looks like it is, try to get someone to make you one or try to find the part at a local shop. I know that most ac and parts replacement houses will not sell to the general public. You need to be licensed to buy anything from them. I hope I was of some help! Good luck!

Edited for piss poor grammar!