Air Conditioning - Should I replace evaporative coil?
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videoguy
07-11-07, 03:16 PM
Hi
Our air conditioning upstairs broken couple of weeks back. The fan is working and I can feel the air coming from the vents. The external unit was starting fine as I can hear the noise. But the temperatures stayed same inside the home all night. It didn't get cooler. The a/c unit is made by Trane and it is 6yrs old.
Today I called a professional. He checked the freon levels. Told me that the freon level is pretty low. He mentioned that there might be a leak. He added freon to the system. He said something like 8lbs of freon he added. Then he asked me shutdown the a/c. While it is off, opened covers and cleaned the sides with water from hosbib.
He came with a leak detector tool. We both went inside the attic. It started beeping continuously when he put the device where the eveporative coil is supposed to be. He told me that there is big leak inside. The freon may last for couple of months and it will be back to old stage unless I replace the coil. He quoted $1150 for replacing the coil besides $275 he charged me for filling the freon. He said it is 3 ton coil.
What should I try to make sure the coil is really leaking?
If I really have to change the coil, is the price he is quoting is reasonable?
I appreciate your help.
Thanks
Purs
Our air conditioning upstairs broken couple of weeks back. The fan is working and I can feel the air coming from the vents. The external unit was starting fine as I can hear the noise. But the temperatures stayed same inside the home all night. It didn't get cooler. The a/c unit is made by Trane and it is 6yrs old.
Today I called a professional. He checked the freon levels. Told me that the freon level is pretty low. He mentioned that there might be a leak. He added freon to the system. He said something like 8lbs of freon he added. Then he asked me shutdown the a/c. While it is off, opened covers and cleaned the sides with water from hosbib.
He came with a leak detector tool. We both went inside the attic. It started beeping continuously when he put the device where the eveporative coil is supposed to be. He told me that there is big leak inside. The freon may last for couple of months and it will be back to old stage unless I replace the coil. He quoted $1150 for replacing the coil besides $275 he charged me for filling the freon. He said it is 3 ton coil.
What should I try to make sure the coil is really leaking?
If I really have to change the coil, is the price he is quoting is reasonable?
I appreciate your help.
Thanks
Purs
Ed Imeduc
07-11-07, 03:33 PM
8 lb of freon for a 3 ton does sound high to me. Why didnt he find the leak and see if he could fix it? If it was that big. Before he said you need a new coil. Id call around for more bids.
videoguy
07-12-07, 06:23 PM
I asked the guy the same question whether it is possible to fix the leak.
He said that the coil is horizontal type coil and if you straighten it out, it could be 400 ft long or something like. So it won't be practical to find out where it is. He also told me that he finds these leaks a lot (1-2 a day). That the coil is made of aluminium and it will have a leak after 4-5 years.
Thanks
purs
He said that the coil is horizontal type coil and if you straighten it out, it could be 400 ft long or something like. So it won't be practical to find out where it is. He also told me that he finds these leaks a lot (1-2 a day). That the coil is made of aluminium and it will have a leak after 4-5 years.
Thanks
purs
cdr2183
07-12-07, 07:07 PM
It's impossible to stretch out a coil although there may be close to 100ft of copper length within a coil.
The fact that the tech went to the coil with an electronic leak detector and found evidence is enough to determine that your coil is leaking, but it all depends on where the leak is. He should've pin pointed the leak for you before condemning the coil.
If the leak is on a U-bend it can be easily repaired. If it's at the center of the coil than I'd have to go with the tech and say get a new coil.
"What should I try to make sure the coil is really leaking?"
If you want to look for a leak, and are comfortable opening up your unit. this is what you do.
-Turn off the unit and let the freon equalize in the system, this takes a couple of minutes. Turn off the power to your airhandler before you open it so there's no risk of electrical shock.
-Open your evaporator compartment on the airhandler, where the two copper pipes enter, then listen for an audible hiss. If you have a spray bottle fill it with a little soap and water, then spray it anywhere you may think a leak is. If you get bubbles then you got a leak.
That's how you pinpoint your leak, the tech should've done this already.
And 8 pounds is a lot of gas for your system if it's only 3 tons. Check the name plate on the condenser outside and it will tell you the factory chrage.
R 22 xx lbs. xx oz.
That's how much freon your unit needs, maybe a little more if you have an extensive lineset.
The fact that the tech went to the coil with an electronic leak detector and found evidence is enough to determine that your coil is leaking, but it all depends on where the leak is. He should've pin pointed the leak for you before condemning the coil.
If the leak is on a U-bend it can be easily repaired. If it's at the center of the coil than I'd have to go with the tech and say get a new coil.
"What should I try to make sure the coil is really leaking?"
If you want to look for a leak, and are comfortable opening up your unit. this is what you do.
-Turn off the unit and let the freon equalize in the system, this takes a couple of minutes. Turn off the power to your airhandler before you open it so there's no risk of electrical shock.
-Open your evaporator compartment on the airhandler, where the two copper pipes enter, then listen for an audible hiss. If you have a spray bottle fill it with a little soap and water, then spray it anywhere you may think a leak is. If you get bubbles then you got a leak.
That's how you pinpoint your leak, the tech should've done this already.
And 8 pounds is a lot of gas for your system if it's only 3 tons. Check the name plate on the condenser outside and it will tell you the factory chrage.
R 22 xx lbs. xx oz.
That's how much freon your unit needs, maybe a little more if you have an extensive lineset.