Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

Coleman/Evcon MH furnace

S EbelsS Ebels Member Posts: 2,322
I noticed you said "another company replaced the furnace a couple years ago". Did this replacement include a new roof jack? If not, your customer may have a venting problem. Coleman had a lot of "issues" with the inner pipe becoming perforated and allowing flue gases to be recirculated back into the combustion chamber. We run into a couple of these every year the way it seems. Pilots that won't stay lit, smells, poor looking flame, CO are all symptoms that occur when you have one of these go bad.
Get up an the roof and check it out with a flashlight. Another thing we have found on these POS furnaces is that debris and rust from the flue will fall down and acculmulate on top of the flue baffle, which is right at the top of the HX. This causes a restriction in the flue and can lead to some really wierd things going on with the furnace. Check that out too. The fix for this is to drop a shop vac hose down the flue and try to suck it out. If that won't work due to the debris being a solid pile of rust, the only thing you can do is get a long piece of pipe or a broom stick and push the baffle down to allow for sufficient exhaust area. This obviously reduces the efficiency of the furnace but it's about all you can do short of pulling the whole thing out and cleaning it.

Probably the best thing you could do for your customer would be to sell them a new ThermoPride mobile home furnace. These are without a doubt the best made furnaces on the market for mobile and modular homes. The Coleman is an accident waiting to happen.


  • GlenGlen Member Posts: 855
    elderly client

    smells "gas". This was 2 years ago - a few short months after another company installed a new furnace. After a small parade (installer, gas inspector, other interested parties) through the house - I look. We tested everything and for everything - 1 ppm CO through the house (gas range is almost always on - she bakes the most incredible goodies). All I found was a small LPG leak on the gas valve. Replaced it under warranty.
    Now - 2 years later - the complaint of a gas smell is back (same parade, me too but I find nothing!) So we have the unit turned off - gas off etc.
    There is product notice for these furnaces - but this model falls outside of the notice model numbers. Notice lists combustion chamber burnthrough and insulation burnthrough - but I find nothing. I would like to replace the furnace - for everyone's peace of mind - but there seems to be a lot of nodding and bobbing, and shoulder shrugging - but no one has stepped up (eg, manufacturer) to say yes - let's replace it. any ideas????
  • EdEd Member Posts: 284
    coleman furnace

    Glen - it appears you have performed "due diligence, however, some things come to mind:
    - dog in building? ("natural gas")
    - possibly sewer gas? wc waxseal leak?
    - dry trap somewhere?
    - gas leak @ some other location - neighbor/ meter/regulator/gas flex?
    - possible flue gas drawn into building thru make-up air?
    - exhaust damper stuck open, allowing reverse flow into bldg.
    - we have found several odor problems related to wc waxseals deteriorated. Also in older bldg. the vents can get plugged & cause trap siphoning & odors.
  • RangerRanger Member Posts: 210

    You should be working thru your local Coleman distributor for answers.That's suppose to be there job.If you are not getting the support you feel you need please e-mail me and I will try to point you in the right direction.I have to initally agree with Ed but I am also curious if the roof jack was also changed when the new furnace was installed.The vast majority of the furnaces in the recall were found to be overfired,BTW.Hope this helps.
  • Joe GrossoJoe Grosso Member Posts: 307
    I agree

    Possible roofjack issue. I really dislike Colemans alot. I do not care for them at all. A good 25% of my business is Mobile Homes, so I've been there so to speak.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • GlenGlen Member Posts: 855
    thanks -

    I didn't check on the roof this visit - but did two years ago - essentially to check placement of venting - all was new and in place. Even looked down the warm air plenum for lost animal (deceased) etc. but back to the venting - it makes sense that if the plumbing vent was close by the stack - fumes could be drawn in. Re - overfiring - pressures are set to spec with allowances for our high alt (3500 ft) - but it too makes me wonder if I should not take a LPG meter set with me to correctly check the unit. The old folks (did I tell you that baking happens daily???) are keeping warm with electric and are comfortable. I have made inquiries through my supplier to see if there is any interventions available (eg new furnace)and that discussion is still under way. I don't do much scorched air now - but served my aprenticeship with an Intertherm dealer - troubleshooting has not changed - but I am scratching my head on this one. Oh Yes - one small dog - non smokers, no candles - no pot pourri - no cat.
  • EdEd Member Posts: 284
    Coleman roof jack

    Just for dicussion: The coleman mobile home furnace is a sealed combustion, direct vent appliance? Therefore, the only way to get a gas smell from the unit is prior to the combustion chamber unless: 1) the heat exchanger is damaged, 2) the roof jack is not properly installed, ie: the outer flue sheild not attached to the furnace as required. Any other problem with the roof jack (inner flue apart,plugged, or crown assy. rusted out, should cause the unit to shut down. If not correct or complete, please enlighten me.
  • WeezboWeezbo Member Posts: 6,232
    this is something different to mull over,...

    the average wind speeds and direction. ?

    if the stove is a down draft ,..perhaps it requires make up air to balance the air exchanges...
  • Joe GrossoJoe Grosso Member Posts: 307

    That's true Ed, a bad roofjack will usually cause a 3 flash malfunction. Pressure switch.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • RianSRianS Member Posts: 104

    Your correct Ed, the only way for a gas odor on this model is a fuel line or gas valve leak. I have installed many of the Coleman furnaces and the only problem I have noticed recently is the pressure switch stuck closed.
  • GlenGlen Member Posts: 855
    Gentlemen -

    Everything looks like it is new out of the crate - and I am leaning to prevailing winds, proximity of plumbing stacks etc, and perhaps other air quality issues. Local dealer has been most helpful with suggestions - as has the Wall.
    I am trying plumbing vent extensions first - and go from there.
This discussion has been closed.


It looks like you're new here. If you want to get involved, click one of these buttons!