Air Handler/Duct Mold Removal Recommendations & Price (furnace, AC, vacuum)

[Marzer]

Hi All,

I recently had an issue with my AC recently and have had two AC companies come out and have observed mold in both the air handler as well as the ducts. I live in South Florida so this is very common (especially in a 20 year old house). I received a quote, but it seems high to me so I was curious to see if anyone had any experience with this issue or could provide insight into pricing. The quote was as follows:

Air Handler cleaning: $410
Air Duct cleaning: $425

They also recommended a UV light, which would be $645

$1480 seems a bit excessive for mold removal in my opinion. Does anyone have any experience with this process or things I need to look out for?

[btuhack]

What was the issue? What kind of system? What kind of ductwork?

[Marzer]

The above quote is only for mold + cleaning. I also had to replace a leak on the outside unit + recharge freon. The whole deal started with a funny sound coming from the motor. I was told it would need to be replaced in the next 6 months, but they recommended letting it run til it died in the winter to save some money.

Not sure of the specific duct structure, the house is about ~2000 sq. footage

[btuhack]

I'm skeptical. If I were you, I'd pay for an impartial opinion from someone qualified that doesn't offer duct cleaning. Duct cleaning is for the most part a scam. The primary issue is explaining why the ducts are dirty. A proper filter (not a 1'' pleated, more like 4") should keep everything clean enough to avoid cleaning...ever. Will the blower wheel be pulled and cleaned too? Blower wheels accumulate more dust than the ductwork.

A uv light can be a good thing or a bad thing. Some produce ozone which isn't something you want indoors. Only buy a light that has a 254nm wavelength.

If you really do have a mold issue that needs to be addressed, $1500 bucks would be a bargain to completely resolve. Like I said, I'm skeptical.

[Marzer]

Thanks BTU. The filter is 4.5" thick and is one of these:

Amazon.com - Trion Air Bear 255649-102 Replacement Filter - 20x25x5, Three Per Box - Replacement Furnace Filters

I was given no information about the wheel. It looks to me like there is mold on the outside of the AC handler as well as the insulation inside the unit, but I am also skeptical. They peeked inside the vents quickly but didn't do any testing, etc. I just opened it back up to look further and there is moisture, but I am in South Florida and the AC handler is in the garage so I would expect some moisture.

We moved in not too long ago, so obviously I need to clean the outside as it is pretty disgusting, but the mold was hidden due to a strip that was in place. The AC company removed it when they looked at it and I wanted to show what it looks like currently to give a better perspective.

the coils look really good to me by the way (outside the rust). We were told by both AC companies that it is an expensive unit. The first company immediately said the whole AC would need to be replaced (Lindstrom, and that was obviously a scam). The second company said it had a good 7 years left but that the mold would require a UV light. I have attached pictures below:

[btuhack]

Great filter. The dust build up doesn't look too bad but the mold/mildew needs some attention. I'd pull and clean the blower, vacuum the interior insulation and treat with a mold/mildew inhibitor. The coil looks good on the downwind side but the interior is concealed by the triangle shaped piece of tin. I'd clean the interior side of the coil and treat both sides with a sterilizing cleaner made specifically for the job. You'd need two uv lights to be effective as there's not enough clearance between the coil and blower housing to cover both sides of the coil with one bulb.

I think you'll have limited success with duct cleaning but if you follow thru, the ductwork will have to be dry to have any success. Perhaps a task best left for fall. I'd guess you have a flexible duct of some sort. With the interior wrinkles, a complete cleaning is impossible, leaving a food source for any mold/mildew that comes along.

Heatpumps are notorious for breeding mold/mildew while a gas fired furnace will produce a temperature hot enough to kill/manage the growth.

[Marzer]

Thanks btu! I really appreciate all your help, sorry for the delay in responding. If we don't get the 2 UV lights how likely is it that the mold will come back? $450 for cleaning of the inside of the handler seems better than $2,000 for 2 lights + cleaning but if it's only a 6 month fix then I guess we should go for the whole shebang, huh?

[TrapperL]

I've never been one to go along with the crowd. I think you're being scammed. In the pic that shows the name plate Maytag, just below the A coils would be the primary drainline. It's wrong if it were installed here. It would require a T inline at the unit so the home owner can put bleach in the line to keep mold and algae from forming and blocking the line. The next item is you have mold all over everything. Where is the moisture coming from? If it were working correctly, the moisture is condensed out of the air on the A Coils. It runs down the A Coils to a pan and it runs the water to the drainline and it's gone. Obviously, your system isn't doing that yet they want to treat the unit for mold but not fix the problem. Doing the suggested work only means you'll be doing it next year too. If you can get to the A Coils yourself, a spray bottle of 1/4 bleach and water will kill any molds on the coils. You can buy an A/C comb most any where and clean them yourself. It's not rocket science, just dirty. Around here, you can get all of the ductwork replaced on a 2000 sq ft home for less than they want for the entire cleanup. If you were my brother, I'd strongly suggest having someone else look at the unit and ask why is the mold everywhere and how to fix it. Then address the cleanup. I'd also have them evaluate the Air Bear. Many times these filters become clogged early and slow air flow down. Unless you have a health problem and NEED the extra clean air- I'd get rid of it. Icing happens and the coils never get the chance to dry out. If that is a high end Maytag unit, it will have a timer that lets the fan run up to several minutes past the compressor shutting down. I'd make sure it runs the max amount of time.

[chet everett]

Originally Posted by TrapperL

I've never been one to go along with the crowd. I think you're being scammed. In the pic that shows the name plate Maytag, just below the A coils would be the primary drainline. It's wrong if it were installed here. It would require a T inline at the unit so the home owner can put bleach in the line to keep mold and algae from forming and blocking the line. The next item is you have mold all over everything. Where is the moisture coming from? If it were working correctly, the moisture is condensed out of the air on the A Coils. It runs down the A Coils to a pan and it runs the water to the drainline and it's gone. Obviously, your system isn't doing that yet they want to treat the unit for mold but not fix the problem. Doing the suggested work only means you'll be doing it next year too. If you can get to the A Coils yourself, a spray bottle of 1/4 bleach and water will kill any molds on the coils. You can buy an A/C comb most any where and clean them yourself. It's not rocket science, just dirty. Around here, you can get all of the ductwork replaced on a 2000 sq ft home for less than they want for the entire cleanup. If you were my brother, I'd strongly suggest having someone else look at the unit and ask why is the mold everywhere and how to fix it. Then address the cleanup. I'd also have them evaluate the Air Bear. Many times these filters become clogged early and slow air flow down. Unless you have a health problem and NEED the extra clean air- I'd get rid of it. Icing happens and the coils never get the chance to dry out. If that is a high end Maytag unit, it will have a timer that lets the fan run up to several minutes past the compressor shutting down. I'd make sure it runs the max amount of time.

I am not going to say that you are being "scammed" but I agree that there are issues that do not seem to be addressed.

I have seen LOTS of bad installations of good equipment result in a giant mess and that appears very close to what is happening hear. A properly installed forced air system absolutely HAS to allow for the correct flow of condensate away from the unit or the result will be out of control mold. Similarly if the system does not have proper air flow due to poorly maintained or incorrectly sized filters there can be a range of issues including icing, and insufficient moisture removal. Given the poor state of this unit it would be wise to get some actual pressure / volume measurements along with manualJ calculations to ensure things are properly sized.

I know that commercial UV mold prevention lights work pretty well because the air is basically ALWAYS being pushed through the plenum, in contrast residential systems typically cycle off very quickly and it is not at all clear if there truly is enough exposure to the UV to really kill the spores.

Any reasonable handy DIYer could clean the unit up in an hour or so BUT if the ROOT CAUSE is not addressed the "zoo" will be growing again in no time. Keep talking to MORE professionals until you get somebody that is willing to TEST and MEASURE not just "upsell"...

[btuhack]

Originally Posted by Marzer

If we don't get the 2 UV lights how likely is it that the mold will come back?

Some level of mold will come back. Mold needs moisture and food...anything organic like dust or the paper schematic glued onto the blower assy. UV lights are the best way to minimize the problem after the clean up. Do you need two? you need complete coverage of the coil as it sanitizes only what it shines on and the coil is the most logical point of germination. Honeywell bulbs are 14'' long.

Backing up a bit, why do you have so much moisture inside the cabinet? The relative humidity level on the leaving side of EVERY A/C coil is above 95% or so at 55 degrees...it's nearly saturated air. Slowing the air flow whether it be spinning blower wheel slower or a restricted filter will remove more moisture from the air and deposit it down the drain at a higher rate. That's an important process to have in a muggy region. Running the blower after the cooling operation is terminated is the worst possible thing you can do in a humid region. Any moisture on the coil warms up and re humidifies the air. The moisture during cooling remains airborne because the interior components are the same temperature as the air. That changes after the cooling turns off. When the fan runs after the cooling terminates the air conditions change quicker than the surface temperatures and the moisture wants to stick and condense on everything inside because the components are now colder than the air passing over them. Everything gets very wet, over and over and over.

The other issue is how big a deal do you want to make out of this. In the 28 years I've been in the HVAC trade, I've never been a guy that took general safety issues too seriously beyond safety glasses. Last year I did some work in a floral walk in cooler that was being remodeled. The owner was cleaning a (dry) cooling coil that was cruddy with dirt and mold while I was resolving some leaks. He was wearing a mask while I didn't. Guess which guy had little lung function that night and wound up in the ER the next morning.

I'd install the light(s), clean the equipment with a product specific for the task, and be certain that the fan runs only with the compressor during the cooling season. I'd revisit the situation annually.