Options for a plugged evap coil

[zbxb006]

Split A/C with gas heat...

Compressor died and I had it replaced by a 'Carrier authorized service' company. Their work was not the greatest - no nitrogen purge, no filter/dryer, no thermometer to do a sub/cool check - did it by setting the pressures to 'what they always set them at', regardless of temps, based on 'years of experience'. From the age of the tech, those years couldn't have been more than 2 or 3.

I contacted the owner who came out to inspect the work and said it was fine.

The system ran well for about two weeks and then started falling off. Register temps 5 feet from the evap were only 5 degrees cooler than room temp.

I called the owned back out and he declared the evap coil partially blocked. Said it was old and needed to be replaced. It is 10 years old, but has very little use, under 1,000 hours. He said it was completely unrelated to their earlier work. I suspect that it is indeed blocked, and probably with crud from the burnt out compressor (or their soldering) that didn't get filtered out by the non-existent filter/dryer. But I was not able to get anywhere negotiating with them. They quoted a fairly high number to replace the coil.

I plan on getting a second company to inspect the situation. But a few questions so I can be prepared.

1. Is there any way to confirm that the coil is really plugged up?

2. Is there a way to unclog it if it is plugged up? I realize that there are some pretty small tubes distributing the freon at the coil, but I would also think the piston would be the smallest restriction and a natural place to get a log jam.

3. Is there something else that woud cause the decreased temps? Well, knowing a little about A/C I know there could be a whole bunch of causes, but what might be the most likely, given that they replaced the compressor?

Thanks

Bill in Phoenix

[captube]

Leak

3. Is there something else that woud cause the decreased temps? Well, knowing a little about A/C I know there could be a whole bunch of causes, but what might be the most likely, given that they replaced the compressor?

[zbxb006]

No leak. They checked it when they declared the coil blocked. And then I double checked it myself.

[skippedover]

Get the second opinion and then make your decision. Sure, you could have someone pull the coil, spend an hour or two trying to flush it out, put it back in and find out it's still clogged. Better to get a reputabel, knowledgable company that works with industry standard good practices (like nitrogen purge, liquid line drier, suction line drier, etc.) and just replace the coil. It will cost you a lot less in the long run. Once you've selected the company to do the work, share your displeasure with them so they'll take extra care to avoid any missteps on solving your problem.

[I_bend_metal]

No leak. They checked it when they declared the coil blocked. And then I double checked it myself.

No offense here but how did YOU check it for leaks??

But beyond that....yes, have another company out to take a look at things. Sounds to me like this company that did all of your work....is a piece of work itself. Before they ever even tried to test that AC after the compressor they should have verified the airflow...did they do that? Sounds like they are taking you to the cleaners at this point....get a second opinion and let us know how it goes.

[dash]

Going out on a limb here,'Carrier authorized service' ,there is Carrier Factory Authorized Dealers ,and then all other Carrier folks,which was it?

Either way ,what you describe is less then what you should have have expected.

[AcDOCnTRAINING]

Excuse the expresion, I think you got things done half azz. Was the last compressor lost a burn out , if it was they hole system may be contaminated. I would strongly recommend calling a diffrent contractor, don't be affraid to ask for someone with real knowledge in the field.

[catmanacman]

sounds like they dont have a clue they should have checked the coil for cleanliness checked the metering device blew out the system and if the compressor was grounded installed a suction line drier plus a liquid drier

[mesahvac]

hey zbx sometimes there is a filter built in on your metering device it could be that maybe your coil isnt plugged but what do i know im not there look up straface mechanical in yellow pages heard a pretty good residen. company good luck

[classical]

They sholuld have installed a new coil iwth that new condesner in the first place.

[bell3156]

I'm not a carrier dealer but I'm in phoenix
Is this a rooftop unit? If so there are 2 screens located befor the metering devices on that unit, if you look in the compressor area while the unit is running, you should see freezing around these if it is partially blocked. This is a very common problem on carrier and some older ruud units that used the same screen, even if you install a filter drier it could be plugged, On the splits it has a screen before the metering device outside of the coil, what I found clogging these most of the time was the insulation from the compressor wires melting, then cooling sending small plastic peices plugging the filters, on the pack units, the screens look like small bullet driers.

[iraqveteran]

Split A/C with gas heat...

Compressor died and I had it replaced by a 'Carrier authorized service' company. Their work was not the greatest - no nitrogen purge, no filter/dryer, no thermometer to do a sub/cool check - did it by setting the pressures to 'what they always set them at', regardless of temps, based on 'years of experience'. From the age of the tech, those years couldn't have been more than 2 or 3.

You have just raised several red flags. I replaced 2 compressors today in a American Standard Heritage 16. Replaced both filter driers, Acid Away treatment, Nitro pressure test/purge, triple Evac to 50 microns, cleaned coils, recharge system to factory charge, then charged system to subcooling and superheat. Also replaced factory start assist capacitor and start relay (cause of compressor failure). 8 hours of labor but the system is back up and running at 100% efficiency.

You need to get a new contractor. And you need to contact your old contractor and get things straighened out. Another option would be to contact BBB. Its a far stretch but a lot of contractors will make it right to avoid any complaints to BBB.

Keep us posted on your experiences. Don't allow one bad contractor spoil your taste for the industry. Hope you get your situation resolved in a timely manner.

[iraqveteran]

They sholuld have installed a new coil iwth that new condesner in the first place.

I agree. You didn't get a full diagnosis of the system. The tech should have looked for why the compressor failed as apposed to just calling it a DOA.

The dirty coil should have been caught during the first trip.

[MadeinUSA]

1. Do not even waste your time with the company you used. Just by a few facts you mentioned, they are not following standard industry procedures when performing “major” work on equipment. Just accept it as a lesson learned and move on.
2. Call and get another company out there and let them know what all has happened so they know you are knowledgeable to proper procedures.
3. They should test your system for acid being you had a compressor replacement and no filter(s) have been installed, check your metering device for obstruction, check the static pressure across coil to determine if it is plugged.
4. After that, hopefully they will find your problem and they can go from there to resolve it.
5. There is a good chance they can save your system if they find it acidic. Just have them clean the inside with a good flushing with proper product, and filters installed, and then the large one removed the following day and keep changing until your system is clean. Make sure the little filter is changed each time they change the large filter.
6. Call a supply house of the brand of your equipment, and ask them for a reference for a qualified and trained company that knows what they are doing. Let them know you are knowledgeable and do not want someone who is clueless. Call the contractor and quiz them a little to see if they are open to these suggestions I mentioned, and go from there.

Good luck

[darctangent]

1. Do not even waste your time with the company you used. Just by a few facts you mentioned, they are not following standard industry procedures when performing “major” work on equipment. Just accept it as a lesson learned and move on.
2. Call and get another company out there and let them know what all has happened so they know you are knowledgeable to proper procedures.
3. They should test your system for acid being you had a compressor replacement and no filter(s) have been installed, check your metering device for obstruction, check the static pressure across coil to determine if it is plugged.
4. After that, hopefully they will find your problem and they can go from there to resolve it.
5. There is a good chance they can save your system if they find it acidic. Just have them clean the inside with a good flushing with proper product, and filters installed, and then the large one removed the following day and keep changing until your system is clean. Make sure the little filter is changed each time they change the large filter.
6. Call a supply house of the brand of your equipment, and ask them for a reference for a qualified and trained company that knows what they are doing. Let them know you are knowledgeable and do not want someone who is clueless. Call the contractor and quiz them a little to see if they are open to these suggestions I mentioned, and go from there.

Good luck

While others here have made correct staments, MadeinUSA has more or less given you the full deal in one post.

Print this out and run with it.

It sort of goes with out saying, but they also need to check for moisture in the system.

Did they use a vacuum pump to remove air&moisture from the system? even if you saw them using one it doesn't mean they did it right.

Don't complain about price; complain about quality.

[snack pack]

i don't know if i should ask, but who was the hack contractor?

[smilies]

what I found clogging these most of the time was the insulation from the compressor wires melting, then cooling sending small plastic peices plugging the filters, on the pack units, the screens look like small bullet driers.

What's up Mr. Bell, I remember asking you about that when I tried resi service. Little balls of red, white and black. It was a "duh" moment for me. Wrong Kickstart on a Scroll.

[bell3156]

What up brotha...How ya been?

[zbxb006]

Thanks for the advice. I have found a small local company that seems to have a good rep (few and far between if you know the Phoenix reputation for HVAC).

Several of my neighbors are HVAC techs and they wouldn't even recommend their own companies. What a sad state of affairs. Seems that the good techs aren't allowed to spend the time to do a proper job. With people like 'chainsaw charlie' setting the standards in Phoenix, they seem to think the only way to compete is to lower their own standards and take the same short cuts as charlie.

Anyway, unless they find something minor, I think I've convinced myself to replace the coil and do a complete flush of the system. I'll let you know.

[darctangent]

Thanks for the advice. I have found a small local company that seems to have a good rep (few and far between if you know the Phoenix reputation for HVAC).

Several of my neighbors are HVAC techs and they wouldn't even recommend their own companies. What a sad state of affairs. Seems that the good techs aren't allowed to spend the time to do a proper job. With people like 'chainsaw charlie' setting the standards in Phoenix, they seem to think the only way to compete is to lower their own standards and take the same short cuts as charlie.

Anyway, unless they find something minor, I think I've convinced myself to replace the coil and do a complete flush of the system. I'll let you know.

Get a competent contractor that will stand behind their work with guarantees, and do what THEY say.