Duct cleaning and CO detectors

[David Macy]

I had my homes return and supply ducts professionally cleaned last week.

The CO detectors were set off and record a peak level of 130PPM.

The guy said it was from reverse pressure.

It was interesting watching them spend 3+ hours cleaning my system.

Whatg do you think about the CO detectors going off?

[John Adrian Sopher]

Hmmm don't know.  Never had the service done.  What kind of CO detectors do you have that record an actual measurement? 

[David Macy]

This one is in a bedroom and had the 130 Peak level. (Picture was before the cleaning)

The other one is a combination CO and smoke located in the basement and sounded off to.

[Gregory Scheer]

I'm curious.  What was the cost to have the ducts cleaned and did it involve?

Greg

[Jay Markanich]

I thought Nighthawks didn't go off until 400ppm.  I understand that CO isn't dangerous until it reaches 800ppm.

Reverse pressure - what were the ducts drawing in?  Did they use some kind of a generator (even outside) or a vacuum in the car?  Was the generator or car near the house, and if so, near a fresh-air intake for the house?  Where was the vacuum, near the water heater or near the detector that went off?

Do you have a gas water heater and could they have drawn air back down the WH vent tubing?  If so, how did the CO from the back draft get to the bedroom where the detector went off?

Hard to know without seeing the crime scene, but you might start with answering those questions...

[Jay Markanich]

In Virginia, it depends on the length and number of returns that need cleaning, but it runs $300-400. I recommend to my clients that they get the service that brushes and vacuums.  

If a fungicide is sprayed afterward, it costs more.

[John Adrian Sopher]

Yeah I wish I could have only spent $300-400.  A year after I got my house I had to replace my H/A and the ducts.  I went from rusted out ducts in the foundation to attic ducts.  $2000  

[David Macy]

I paid $350.

They had a large vacuum outside.

The guy said the reason they went off is reverse pressure.

They cut a 8 inch hole at the plenum and cold air return. They drill small holes at each section of supply vents that have seperate sections. They use whip(aggitator) to loosen the dirt. The talk off the return air vents and vacuum. The use an air hose for the supply.

They plug the small holes with plastic caps. They cover the large holes with shhet metal.

The guy said when we do an inspection take the cold air return off by the nearest entrance and show the clients the dirt. (Beyond SOP)

We did notice a small layer of dirt on most areas of the home due to how dirty the ducts were. 44 years worth

They did a good job, I would recommend them.

[John Adrian Sopher]

I always recommend cleaning ducts on older houses.  Most people don't think about it or think its very low on their to do list.

[Jay Markanich]

Dave - from what you describe it could be that they drew air down from the water heater vent and up towards the bedrooms.  Do you have gas appliances?  I can't think of where else reverse pressure would have gotten the CO from.

I don't take off the covers, but I always show people any built-up stuff with my flashlight.  I tell them that it is more than just dust, but also accumulated organisms...  that gets them to understand.

[David Macy]

Yes I have a gas water heater.

For 300-400 dollars a well worth investment.

Will go into my Improve section.

Need to come up with some verbage. Care to offer an example.

Here is mine.

Improve: Now acknowledged as a major allergy and disease causing problem by leading medical authorities, poor indoor air quality has prompted doctors and allergists to commonly prescribe furnace and air duct cleaning as a remedy. Duct cleaning can reduce heating and cooling costs by allowing your system to operate more efficiently. Moreover, duct cleaning can cut maintenance cost because a clean system has fewer breakdowns. Standard throw-away fiberglass filters remove less than 7% of these particles, which means much of the rest settles in your air ducts. Contact a qulaified contractor to perform the duct cleaning process.

This is long and I need to work on the comment. Any ideas are welcomed.

[Jay Markanich]

I think $300-400 is well worth the expense!  For so many reasons.

As to your verbiage, it is not too long.  The length emphasizes its importance.  I would say only to change one thing -- "Moreover, duct cleaning ALONG WITH REGULAR SERVICE can cut maintenance costS because a clean system has fewer break downs AND CAN LAST LONGER."  That's a super paragraph Dave.   

On my reports I routinely recommend an allergy-free filter.  I have used them from day one in my house (10 years old) and every time our HVAC guy comes for my annual service he comments on how clean the systems are.

[Steven Turetsky]

Maybe it's a regional thing, but I find it hard to believe that it would cost  $300-$400 in NYC to clean the ductwork in a n average home. The company I used to work for bought a duct cleaning system just before I left. I also doubt that they would have bothered for that amount.

Perhaps I will inquire.

[Jay Markanich]

I have an annual service on my HVAC system, two units, and it costs $160.  That's two visits, fall and spring.  I doubt you could find that price in NYC either!!

Some clients of mine just had their ducts cleaned, three-level townhouse, one system- and it cost $300 including fungal spray into the ducts after the cleaning.

[Steven Turetsky]

Like I said, I think I am going to try to get some more information on the subject. It just seems like a small amount to pay when you take into consideration purchasing the equipment, supplies, salaries, insurance, vehicle insurance, advertising, office support, etc, etc.

I am considering getting into mold remediation and thought about duct cleaning.

[Stephen Stanczyk]

We had ours done about a year after we moved in.  They used the rotating brush and vacuum so they did not have to cut holes in the plenum.  They charged by the register.  I think they ran a special of $9 per.  Had them sprayed with the fungicide also.  I think total cost for the house was about $200.  They also sold me on electro-static air filters at the return air vents.  Once the system was clean, it was easiest to keep the whole thing clean by filtering all the air before it got to the equipment.