major MOLD Problem !!!!

[SuperTech2010]

2story home...3ton...10seer...11years old...zoned (upstairs and down) with bypass... metal duct...condensate pump... return sized at 200sq. per ton...flex drops to boots... R-4.2........ heats and cools just fine. There is mold thru out the entire downstairs supply and return. Heavy mold a half inch thick in some places. The mold is everywhere. The boots, flex, and trunk all. Airhandler has got some but not as thick. There is no mold from damper to upstairs. i have never seen mold this bad before. The H.O. are very clean people, eat from the floor clean. Only been living there 1year tho. thanks for any help as always:cheers:

[Pion]

Is there a humidifier by any chance?

[energy star]

Is the condensate actually being pumped or is it leaking into the duct.

[hvacvegas]

Is there a humidifier by any chance?

Thats the first thing that hit me.
A unlevel humidifier is a mold factory.

[SuperTech2010]

no humidifier...and yes the condensate is leaving the primary pan thru the drain pipe(with trap) to the pump(4ft away), and pump is working.

[mdharris68]

What does the inside of the evaporator coil look like? And is the drain trapped as per mfg specs if necessary? Just sayin'

[SBKold]

Cool, dark, and damp - that is what mold needs to grow.

Figure out why the internal ducts are damp.

Or add UV lights - take something out of the equation.

[teddy bear]

A/c ducts are damp 24/7 during the cooling season.
After cleaning or replacing the ducts, provide a "dry time" everyday that thoroughly dries out the coil and ducts for a couple hours to prevent mold from growing. Maintain <50%RH in your home, basement/crawlspace with a whole house dehumidifier. The dry air from the dehumidifier could be distributed to the home via the ducts which will also keep the ducts dried out.
UV lites are only effective within a couple feet.
Regards TB

[walterc]

Most of the moldy ones I find have one or more conditions.
Here it is very humid, you may be different in your area.

1. Customer always runs the blower in "on" position on the tstat.
2. Has refrigerant leak and constantly runs low on freon. (Has it charged once a year for example).
3. Improper charge also.
4. Bad metering device.
5. Restrictive ducting.
6. Never changes filters.
7. Airflow- static wrong.
8. Runs the system at lower than normal temps- (example- 68*).
9. Dirty system.

Basically- airflow or temp problems.

[ChaseAir]

A/c ducts are damp 24/7 during the cooling season.
After cleaning or replacing the ducts, provide a "dry time" everyday that thoroughly dries out the coil and ducts for a couple hours to prevent mold from growing. Maintain <50%RH in your home, basement/crawlspace with a whole house dehumidifier. The dry air from the dehumidifier could be distributed to the home via the ducts which will also keep the ducts dried out.
UV lites are only effective within a couple feet.
Regards TB

Properly sized ducts should never be damp. Clean them? How do you clean ducts, especially if they have mold? I suppose that big shop vac thing won't do it, would the vaporizer that people fill with the perfume disinfectanct clear it all out?

[smooth_operator]

Here is some moldy duct work before and after cleaning. This is not a final product. After cleaning all that insulation liner will be coated with fungicidal protective coating. It will be applied with special airless sprayer rig. Very cost effective in most situation.

http://images53.fotki.com/v52/photos/2/1057222/10039080/lerch037-vi.jpg
http://images112.fotki.com/v1531/photos/2/1057222/10039080/lerch044-vi.jpg
http://images59.fotki.com/v684/photos/2/1057222/10039080/lerch035-vi.jpg
http://images114.fotki.com/v74/photos/2/1057222/10039080/lerch043-vi.jpg?1315155656
http://images114.fotki.com/v1606/photos/2/1057222/10039080/lerch040-vi.jpg?1315155623
http://images108.fotki.com/v205/photos/2/1057222/10039080/lerch041-vi.jpg

[chiefPE]

What does "return sized at 200sq. per ton" mean? sq inches? Why does that matter? Sounds like the AC is sized to big for the house. Is the mold only in the duct or is it also in closets? What do they keep the t'stat set on and what is the sf of house, size unit, cfm, discharge temp? Need that info to find out why the %RH is to high. Do you know what the %RH is in the house? If the %RH is 50 or less will not have mold. Oh, yea where is the return & supply duct located? Need more info to solve problem.

[ChaseAir]

[QUOTE=smooth_operator;11204142]Here is some moldy duct work before and after cleaning. This is not a final product. After cleaning all that insulation liner will be coated with fungicidal protective coating. It will be applied with special airless sprayer rig. Very cost effective in most situation.

[url]http://images53.

How did you do that?

[smooth_operator]

We do it with air duct cleaning tools.
We use power vac truck and compressed air duct cleaning system. It's NOT rotobrush.

[ChaseAir]

We do it with air duct cleaning tools.
We use power vac truck and compressed air duct cleaning system. It's NOT rotobrush.

Abatement tech?

[smooth_operator]

Power vac truck, 10,000 cfm at 15"wc vacuum with filters in place.
It's not just power of vacuum that cleaning it but however both high volume vacuum and proper cleaning tools. We use compressed air systems. Our power vac truck has on board air compressor that supplies 250 psi at 60cfm non stop.
I'm sure they will remove my posts ;-)

[energy star]

Roto is a toy

[SuperTech2010]

thanks for all the help guys......the problem was supply duct sizing....sizing supply too small to make up for when both zones have a call...replacing entire system

[Mille Racer 69]

Activ tek air scrubber.
I have personally seen it make mold flake off walls.

[hvacker]

If it's as bad as you say I think I'd involve a company that specializes in mold mitigation. If you do it yourself and the HO thinks they are sick your the one some lawyer will snag.
Very few hvac companies, if any, have the ability to test and certify for molds and you will need this if you get sued.
BTW lawyers really like the word mold.
A flooded building I was involved with had to remove and scrap all ducting, fan coils and 4 feet of drywall in the entire first floor. Then people came and tried to grow mold in vitro. Big $$.

[tinknocker service tech]

no suprisbite the bulet and have it replaced with madal wrapped e it is fiberglass duct
i am about to set off a flame war but get rid of that fiber duct it is famos for mold grouth
replace it with wrapped medal ducts and flex take offs
trying to fix that stuff is costly and in the end nowin


replace it

[genduct]

no suprisbite the bulet and have it replaced with madal wrapped e it is fiberglass duct
i am about to set off a flame war but get rid of that fiber duct it is famos for mold grouth
replace it with wrapped medal ducts and flex take offs
trying to fix that stuff is costly and in the end nowin


replace it

No flames, just facts!!!!
Mold grows when there are two things present: liquid water AND organic material (in this case dirt) Fiber glass is just that INORGANIC GLASS just as inorganic as galvanized.
So look up the info and don't just repeat "old wives tales" i know you aare smarter than that. It is OK to prefer sheet metal if that is your preference without coming up with negatives about other choices.
Mike

[Cooked]

......Mold grows when there are two things present: liquid water AND organic material (in this case dirt) Fiber glass is just that INORGANIC GLASS just as inorganic as galvanized.
..........

You are correct Mike with one caveat. The fiberglass, whether rigid ductboard or a lined metal duct, presents a much greater surface area for the mold to adhere to making it more difficult to mitigate and clean up.

As far the pics posted of the duct (looks like a plenum) all I can say is that's amazing. I have never seen that process in action before. Wow!

[stickinit2thman]

What does the inside of the evaporator coil look like? And is the drain trapped as per mfg specs if necessary? Just sayin'

What is your static pressure on downstairs only zone calling? If bypass isnt balanced correctly it could be blowing water off coil, anyone agree?

[stickinit2thman]

What is your static pressure on downstairs only zone calling? If bypass isnt balanced correctly it could be blowing water off coil, anyone agree?I was in the right area, I saw the post of the solution after my post so I was close at least.

[ChaseAir]

You are correct Mike with one caveat. The fiberglass, whether rigid ductboard or a lined metal duct, presents a much greater surface area for the mold to adhere to making it more difficult to mitigate and clean up.

As far the pics posted of the duct (looks like a plenum) all I can say is that's amazing. I have never seen that process in action before. Wow!

The pictures are hard to believe. What caused the mold to begin with? If the problem I'd not solved, it will surely come right back. How does moisture get into ductwork, but by design issue?

[tinknocker service tech]

genduct
you are correct. I am not a fan of fiber duct although have worked with it many times. Not as duct work but for sound profing chambers for industrail wood cutting and planing machines

needless to say most old duct with fibir or liners seem imho to build mold more so then just plane rapped madal ducts do

most cases it seems lack of maintance of filters and iceing up from other problem putting excess moisture into the ducts and the prossess begins

sorry for my prejugest statement but i do hate that stuff LOL

[sammyray]

This is an open air handler closet to attic and running system below 65 degrees.

[Chris_Worthington]

No flames, just facts!!!!
Mold grows when there are two things present: liquid water AND organic material (in this case dirt) Fiber glass is just that INORGANIC GLASS just as inorganic as galvanized.
So look up the info and don't just repeat "old wives tales" i know you aare smarter than that. It is OK to prefer sheet metal if that is your preference without coming up with negatives about other choices.
Mike

Mike,

Just a question here, so don't take this wrong way or anything :D

Would not fiber duct have the pockets and the hairs to reach out and grab some material/water?

These pockets and hairs I see as a non issue when it comes to metal duct.

BTW, call me I am off vacation now :D

Chris

[genduct]

You might think so, but on the micro level the rough surface of galvanized looks just as rough as liner or board to that dirt!
Also consider the oil on sheet metal that act like flypaper on the sheets, that no one cleans off as per the new requirements (suggestions) of ASHRAE 62
Main point is that both sheet metal and Fiber GLASS are both inorganic and neither will support life (bugs) it is the organic material (dirt) and LIQUID WATER that aare needed for growing bugs.

[genduct]

genduct
you are correct. I am not a fan of fiber duct although have worked with it many times. Not as duct work but for sound profing chambers for industrail wood cutting and planing machines

needless to say most old duct with fibir or liners seem imho to build mold more so then just plane rapped madal ducts do

most cases it seems lack of maintance of filters and iceing up from other problem putting excess moisture into the ducts and the prossess begins

sorry for my prejugest statement but i do hate that stuff LOL

I respect your right to think and say what you believe. I think if you had all the facts you might reconsider, but even if you don't It's OK with me

[genduct]

You are correct Mike with one caveat. The fiberglass, whether rigid ductboard or a lined metal duct, presents a much greater surface area for the mold to adhere to making it more difficult to mitigate and clean up.

As far the pics posted of the duct (looks like a plenum) all I can say is that's amazing. I have never seen that process in action before. Wow!
\
But with the superior insulation the opportunity for condensation providing the liquid water seems to me to be less