WAY OT: Any residential AC repair folks out there?

[bcroslin]

I had my biyearly AC maintenance today and the tech made me crazy. He told me the evaporator coils were dirty and that there was rust in the unit. He also told me my ducts needed to be treated with mastic sealant. This is the first time I've heard that and the ducts are only 6 years old and IMO are in good shape. I went back into my attic when he left and looked in the air handler and things looked fine. There was some rust but after some googling it looks like every evaporator coil show some rust over time. The handler and compressor are only 7 years old and have been meticulously maintained since day 1.

I think the punk was trying to pull one over on me and sell me several services I don't need but I wondered if anyone out there who knows this stuff could give me a second opinion.

[SlackMan]

I don't repair ACs, but my personal experience suggests that often times brand new AC systems are not particularly well sealed. I had the mastic sealing done because there were big gaps (easy for me to see) that caused heat and cool air loss into the attic, and thus wasted bunches of energy.

[unterhausen]

leaks are really common, and a big waste of energy. That being said, the people that would be sealing your system now are coming from the same population that didn't do it right in the first place.

[pbarry]

Originally Posted by bcroslin

I had my biyearly AC maintenance today and the tech made me crazy. He told me the evaporator coils were dirty and that there was rust in the unit. He also told me my ducts needed to be treated with mastic sealant. This is the first time I've heard that and the ducts are only 6 years old and IMO are in good shape. I went back into my attic when he left and looked in the air handler and things looked fine. There was some rust but after some googling it looks like every evaporator coil show some rust over time. The handler and compressor are only 7 years old and have been meticulously maintained since day 1.

I think the punk was trying to pull one over on me and sell me several services I don't need but I wondered if anyone out there who knows this stuff could give me a second opinion.

You can see if the mastic was applied during installation: Usually grey in color and smeared along the duct joints. If it's not there, then the tech may be correct. Worth getting dirty with a head lamp to take a closer look. I'm almost embarrassed to say that I've been in this industry, but always worked for quality firms.. More takers than givers, but there are some good folks out there. Check Angie's List if you can't work this out.

[bcroslin]

Originally Posted by unterhausen

leaks are really common, and a big waste of energy. That being said, the people that would be sealing your system now are coming from the same population that didn't do it right in the first place.

The joints look fine to me even though there's no mastic and I'm not feeling any cool air blowing out at the seams. It's the rust I'm seeing around the evaporator coils that worry me. The coils themselves look good but there's a piece of metal between the coils that is rusty. I've attached an image to show what I'm talking about.

I'm not sure if this new tech is telling me the truth or if the other techs that came before him were lying. I can't ever get a straight answer from these guys and I started to lose my cool today.

[vqdriver]

even if applied, mastic needs a reapplication from time to time. it's not absolutely necessary but probably every installation guide will recommend it.

re the rust, what exactly is the tech proposing to do? is it just a bolted on piece of sheet metal that can be replaced?

fwiw, if it's just the rust and mastic that the tech pointed out, i wouldn't feel taken advantage of. sounds more like a by-the-book guy. no rust is better than rust. mastic is better than no mastic.

[Highpowernut]

That rust looks like built up from poor drainage.
I agree there are lots of crooks in the ac industry.
I do refrigerated trailers, I have to deal with bad ac techs and bad diesel techs at the same time .

Make whoever is telling you you need a repair , how or why it happened and show the problem exactly. Sometimes the tech isn't able to explain it in terms others can comprehend,

[bcroslin]

Originally Posted by Highpowernut

That rust looks like built up from poor drainage.
I agree there are lots of crooks in the ac industry.
I do refrigerated trailers, I have to deal with bad ac techs and bad diesel techs at the same time .

Make whoever is telling you you need a repair , how or why it happened and show the problem exactly. Sometimes the tech isn't able to explain it in terms others can comprehend,

A few friends have recommended an AC tech that they trust so I think I'm going to give him a call next week to check the evaporator. I'm also thinking I'm going to go back into the attic tomorrow and check the joints again and if need be I'll take care of the mastic. It's cool enough and I've got plenty of time between bike rides and opening presents this week.

[bcroslin]

Originally Posted by vqdriver

fwiw, if it's just the rust and mastic that the tech pointed out, i wouldn't feel taken advantage of. sounds more like a by-the-book guy. no rust is better than rust. mastic is better than no mastic.

That's what I'm having a hard time sorting out. The previous techs never mentioned anything this guy brought up. It's never the same tech doing the maintenance and they always have something different to say. I've been told by 3 different techs to use 3 totally different air filters (HEPA, cheap blue and reusable). I've had them tell me my system is top notch and it was smart to install a UV filter and then the tech today tells me where my UV filter is installed it's probably not doing much. I feel like they're all full of s!$%!

[Ken Robb]

Is mastic better than duct tape for sealing joints?

[rnhood]

you can keep paying the tech to check and inspect your unit each year, or you can just run it and enjoy the AC. Its good for about 12-15 years either way.

[Ken Robb]

Originally Posted by rnhood

you can keep paying the tech to check and inspect your unit each year, or you can just run it and enjoy the AC. Its good for about 12-15 years either way.

I kind of wondered about this myself. I had a rust problem just before my 5 year warranty expired that cost me nothing but I expect a recurrence because my drain/condensate line goes uphill. There is a pump that kicks on when needed but I'll bet the pan under the coils stays wetter than those in units that can rely on gravity to drain.

[Peter B]

Originally Posted by bcroslin

The joints look fine to me even though there's no mastic and I'm not feeling any cool air blowing out at the seams. It's the rust I'm seeing around the evaporator coils that worry me. The coils themselves look good but there's a piece of metal between the coils that is rusty. I've attached an image to show what I'm talking about.

I'm not sure if this new tech is telling me the truth or if the other techs that came before him were lying. I can't ever get a straight answer from these guys and I started to lose my cool today.

Check your condensate drain. Looks like things may have been backing up, resulting in the rust you see forming in the condensate pan. The drain line must be sloped for gravity drainage or supplemented by a powered pump. If the line slope is inadequate, pump has failed or lines are clogged you'll get excessive condensation accumulation and resulting rust.

<edit>
On second glance, it looks like you have standing water in there now. You need to clear the line and drain that pan.

[bcroslin]

Originally Posted by Ken Robb

I kind of wondered about this myself. I had a rust problem just before my 5 year warranty expired that cost me nothing but I expect a recurrence because my drain/condensate line goes uphill. There is a pump that kicks on when needed but I'll bet the pan under the coils stays wetter than those in units that can rely on gravity to drain.

I wonder the same thing. My unit is installed horizontally and when I googled the model all I find is photos of units installed vertically.

[bcroslin]

Originally Posted by Peter B

Check your condensate drain. Looks like things may have been backing up, resulting in the rust you see forming in the condensate pan. The drain line must be sloped for gravity drainage or supplemented by a powered pump. If the line slope is inadequate, pump has failed or lines are clogged you'll get excessive condensation accumulation and resulting rust.

<edit>
On second glance, it looks like you have standing water in there now. You need to clear the line and drain that pan.

There's definitely some moisture in there. Should the inside of the air handler be totally dry? I'm in FL and even though its Dec the humidity is still 90%. There's moisture in everything here.