black filter

[zigfried]

I am writing on behalf of my in-laws.

Approx 2.5 months ago, they had a very high efficient York furnace installed, which I believe was 98%.

They have been changing the pleated filter,which was supplied by the company that installed the furnace, every month and it has been very dark in color, almost black. They are concerned, as I am, that there may be a problem.

I can get other info as far as model #, filter brand etc., if it might help.

Thanks for any comments.

[t527ed]

do they burn candles?

[zigfried]

My apologies, as I intended to mention this as I had seen in searching othere posts.

No , they do not burn any candles at all.

[VTP99]

Just a wild guess maybe some other incomplete combustion problems. Gas hot water tank or dryer ? Where is the return air register ?

[zigfried]

Some more information.

The original furnace was approx approx 20+ years old. Obviously the old style, vented thru a stack to the roof (60% efficient?).

With that furnace, the 'old' style filters werre used that I have also suspected didn't trap a whole lot and as I mentioned previously, are now using a pleated version provided by the installer. A dozen was provided and they were advised that they be changed on a monthly basis.

The hot water tank is beside the furnace, also venting thru the stack to the roof. My understanding is that when a new tank is required and if the decision is made to remain with gas, the stack will have to be reduced in size with a sleeve from 5" to 4". I may not be 100% accurate on those measurments.

The electric dryer is in another room in the basement.

There were a couple of additional registers along with a cold air return added to the recroom in the basement when the furnace was installed.

We have called the installer, who thru research was deemed to be reliable and we are awaitng a return call.

I hope to be available when they call, and was hoping to have some thoughts from others before they did.

Thanks again.

[Some Dude]

Sounds like their ductwork is dirty.
I have had to tape cheese cloth over registers on start up before.

I once looked down a return air duct and it was packed with 1/2 inch of black powder from 3 generations of heavy smoking. You inlaws may not smoke, but who did they buy their house from.
Also take into consideration that new furnace is variable speed and probably moves more air, stirring up whatever is still in the old ductwork.

Have the ductwork checked especially the return air.

[t527ed]

Sounds like their ductwork is dirty.
I have had to tape cheese cloth over registers on start up before.

I once looked down a return air duct and it was packed with 1/2 inch of black powder from 3 generations of heavy smoking. You inlaws may not smoke, but who did they buy their house from.
Also take into consideration that new furnace is variable speed and probably moves more air, stirring up whatever is still in the old ductwork.

Have the ductwork checked especially the return air.


agree with this since candles are not the culprits.

let the installer come back and take a look, many times the newer furnaces will pull loose dirt from the return due to the stronger blowers.

[gary_g]

Is there a fireplace in the house?

[captube]

Is there a fireplace in the house?

I was on one black filter that was from the gas log fireplace, damper shut.

[tocss]

how clean do they keep the house. any new carpet or heavy cooking.i removed my in-laws filter and found it black. found out latter that they burnt dinner the night before.

[Sleuth]

Cajun cooking?

[pacnw]

the newer equip can be more powerful, thus moving the dirt off the duct work and to the filter.

when our company installs a new unit, we do a duct cleaning as well. If they refuse, we warn them of just this type of issue.

could be other things like have been mentioned, but my guess is dirty ducts.

[REP]

Do they have ductboard ducts or flex pipe runs?
Could be after 20 years that the black fiber lining on these products are flying off into the airstream.Thats just a wild guess.Is there any slight build up around the supply registers or even return registers?
Of course it could be dirty ducts reacting to a strnger airflo than what they had,in which case a good duct cleaning is in order.

[beenthere]

Is there any internally insulated sheet metal duct?

[lane]

Hopefully it isn't an open return system, drawing in all the musky moldy crawlspace air.

Lane