How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Tim H. Your Own Question
Tim H.
Tim H., HVAC Professional
Category: HVAC
Satisfied Customers: 3966
Experience:  Experienced in all aspects of HVAC, both residential and commercial.
Type Your HVAC Question Here...
Tim H. is online now
A new question is answered every 9 seconds

I have a Coleman 7900 Standing Pilot Furnace (7956 A856) and

Resolved Question:

I have a Coleman 7900 Standing Pilot Furnace (7956 A856) and the pilot light won't stay lit and it has put out a lot of soot. The repair tech said that it was a problem with the fresh air intake and I need a new furnace because this model is so old. Can anybody tell me what exactly the problem might be, because the tech hasn't been able to explain it to me
Submitted: 5 years ago.
Category: HVAC
Expert:  Tim H. replied 5 years ago.
Thanks for giving me the opportunity to help! There are different reasons why a pilot can be sooty. One is that the pilot just needs a thorough cleaning. Take apart, blow out the pilot tubing, clean pilot and orifice. Another reason may be a plugged heat exchanger. This is a fairly big job to clean out all of the soot, etc but can be done. There are 2 ways to tell if your heat exchanger is plugged, visual inspection and a CO test. These are things best left to a professional as he will know what to look for.
But I would certainly get at least one more opinion before purchasing a new furnace as the previous company may just be trying to sell a furnace.
Customer: replied 5 years ago.

Well, I've heard from the previous tech twice and all he offered was that it was something that couldn't be repaired, but all he ever did was to look down the chimney/exhaust out the roof of the house. I actually took the chimney all out to try and see what he said was the problem so I could better understand it and I have failed to see what could be causing a problem with the fresh air intake, which is what the tech claimed was causing the soot. The same tech put a new gas valve/pilot assembly on this furnace about 2 months ago. Is there any kind of a damper or vent piece in the top of this furnace that would fail, he called it a bevel.

Expert:  Tim H. replied 5 years ago.
There are many venting parts both for fresh air and exhaust, but I fail to see why these can't be replaced. Have you gotten a second opinion yet? It sort of sounds like this guy may not know what he's doing.
Tim H. and other HVAC Specialists are ready to help you

Related HVAC Questions