PDA

View Full Version : FURNACE BURNER HOLES PLUGGED WITH DEBRIS FROM HEAT EXCHANGER



thefatguy
11-03-2006, 01:12 PM
Dear members of this Learned Craft,

I have an "ARCOAIRE" downdraft furnace with its tradnamed "RPG" heat exchanger.

BACKGROUND: It has been off for 6 months until the recent cold snap. Well, I turned it on two weeks ago & I could smell natural gas outside. I didnt think much of it - I figured it was a wierd downdraft from the flu-pipe since I live near a tree line. A week later my CO detectors started going off - this all coincided with poor heating performance - this furnace used to drive you out of the house with heat. I swapped the CO detectors around, but in area of the house, near/adjacent to the furnace INLET they all went off.

I took the cover off & fired up the furnace again,#1) the filters were plugged - I cleaned them, #2) I noticed that two of the three - burner tubes inside the heat exchanger, were not alight all the way. One tube was fully lit & it had the parade of blue cones comming off it. However, the other two burner tubes were not lit 3/4 of total length, maybe 2-3 inches of jets were lit. But, the unlit tubes were engulfed in a random blue flame. I looked at all the tubes closer with a flash light & the area underneath all the burner tubes was a pile of black particulate debris. THe tubes with the problems had a noticeably larger piles. THerefore, all I can fugure is it is the heat exchanger rusting away & fowling the burner tubes. MY QUESTION - What should I do. Is it a forgone conclusion that my furnace is toast ? OR ShoudlI have a furnace guy come out & clean & inspect it ? The furnace is exactly 16 years old. It is a 90% efficiency model with electric igniter. My question concerns value - rather than wasting a service call on a guy telling me my furnace is shot ( which I strongly suspect ) - should I just get on with replacing it ? THe reason for this question is because of the CO in the house - is it a forgone conclusion that if CO is in the house - the heat exchanger is shot - or - ( I know there is CO because of the incomplete combustion ) - because the filter were plugged, it was able to suck in CO from the unit because of the vacuum caused by the plugged filters. ? I dont want to throw good money after bad..Since this is a 90% model, Im not as motivated by fuel prices to replace it because of the payback. Please advise - thanks !

comfortdoc
11-03-2006, 02:03 PM
Shut off the furnace and call a technician to evaluate it. It's the only way to know what the condition of the heat exchanger is.

seaeagle2
11-05-2006, 01:27 AM
16 year old rpg heat exchanger with soot, shut off the furnace, you need a new one.

beenthere
11-05-2006, 04:29 AM
Doesn't matter what age a furnace is, if its setting off the Co detector when it runs, shut it off!!!

many companies will waive the service call charge if you have them install a new furnace. Get it checked.

MikeJ
11-05-2006, 04:57 AM
Seen a few of those like that. If you were to pull the burners you would find that the slots in them have rusted up quite a bit. Then the air and gas mixture is such that you are not burning cleanly and soot is being produced. It accumulates in the heat exchanger until it plugs up and the flames now can't even go up into the H.EX. properly. So they escape the unit whereever they can. Cleaning is probably not possible or very costly as is replacing the heat exchanger. Just a heads up for you for when the salesman comes to sell you a new more efficient unit.