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Flue liner necessary?

pweedith
pweedith Member Posts: 7
So I'm a realtor and currently under contract with a client to purchase a 3 family home. We asked for a flue liner to be installed but when the seller's chimney guy came to quote the job he told them that it wasn't necessary. Is this true? We're trying to figure out if we should make him go through with installing it as agreed or if it's something he can skip out on. The seller has gone above and beyond and done things that weren't asked of him so I want to be fair. 

A little more info: currently a clay lining. It is only used for venting 3 gas boilers and 3 gas water heaters.

Thanks for any help. 

Comments

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    If a licensed chimney sweep did at least a level II inspection of the chimney, and if the chimney is sized to properly handle all 6 appliances, then it probably doesn't need a liner, if the chimney company is competent and honest.
    But I'd get a second opinion...
    steve
    SlamDunkpecmsgBob Harper
  • pecmsg
    pecmsg Member Posts: 4,775
    If a licensed chimney sweep did at least a level II inspection of the chimney, and if the chimney is sized to properly handle all 6 appliances, then it probably doesn't need a liner, if the chimney company is competent and honest. But I'd get a second opinion...
    I agree. Not enough information to give an answer. Get a second opinion and post the #’s of the equipment. 
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,453
    @pweedith

    There is no direct answer. Not all chimneys require a liner if they are in good shape. Depends on appliance BTU input, inside or outside chimney? height of chimney and the lowest winter temperature etc
  • Bob Harper
    Bob Harper Member Posts: 1,034
    The chimney must be suitable for the class of service. That requires an NFPA Level II inspection. That removes the guesswork. No more assuming if you see a flue tile sticking out of the top then it must be 'lined'. Lined means continuous and serviceable. In my 36 yrs of inspecting chimneys I have never found one properly constructed. Moreover, I've never found a chimney sweep who found one in the wild that passed except those sweeps who poured the footing to crown themselves. The IRC points you to NFPA 211 as the std. as to what a chimney must meet for gas or oil atmospherically vented. Let me pose a few questions to drive home my point. Does an interior chimney maintain a 2" clearance to combustibles all the way out the building? Is it firestopped at each ceiling level and in the attic? Are all the mortar joints between flue tiles fully grouted and no wider than 1/8"? Did they use a medium duty non-water soluble refractory cement mixture struck smooth with no squeeze out? Are all the flue tiles properly aligned with no staggering? I could go on and on. Suffice it to say every chimney requires a liner to meet code. Often, we have to break out flue tiles to get a larger enough liner in. Lots of guys will cheat and put in an undersized liner, which is asking for trouble. Smoothwall liners don't have to be derated 20% as corrugated ones do. Heater liners don't have to be insulated to meet their listing even with wood touching the chimney. If you seal them top and bottom they become air insulated like a Dewar's Flask aka Thermos bottle. HTH
  • captainco
    captainco Member Posts: 792
    I can't believe a chimney guy that could make some money would turn down a chimney liner job if it needed one, Sounds pretty credible to me.

    The only time I recommend liners is if the chimney is in need of repair or someone has a bladder problem.
    If the chimney is in need of repair then there is a venting problem with the equipment venting into it. A liner will never fix that, but it may make it worse.

    The Fuel Gas Code states that a chimney should not be more than 7 times bigger than the smallest equipment vented into it. Bet this job violates this. Also the Code states the smallest equipment must exit first. Probably another violation. Yet these are allowed in multi-story building all the time. How much of Code is verifiable and how much of it is based on opinion of persons that never worked in the field. Yes we have to follow Code, but that does not eliminate us from liability if things don't work!!

    Something I bring up in class is what type of venting material causes the flue gases to condense the most?
    B-vent! Aluminized liners are next. Stainless is much better but not as good as Clay. They have the highest thermal conductivity to absorb and transfer heat.

    Condensation in flues is caused by poor operation of the equipment venting into it and its environment.

    Do you ever wish the people that told us how to do our job actually knew how to do it themselves? It was stated in an article in GAMA magazine a few years ago that nobody on the Code board worked in the field!
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    edited August 2021
    captainco said:

    I can't believe a chimney guy that could make some money would turn down a chimney liner job if it needed one, Sounds pretty credible to me...

    I read it as the OP (Realtor) has the buyer, and the seller's chimney guy, maybe a friend, maybe not even a licensed chimney sweep but a dude that drops liners is trying to help out his buddy by saying it doesn't need one.
    If the realtor is working for the buyer, he/she has an obligation to help protect their interests.

    In any matters of real estate, I always get my own professionals, to protect my own interest.

    steve
  • captainco
    captainco Member Posts: 792
    Laws of disclosure when selling a house come into play. There can be jail time if some accident occurred because of negligence. Over the years I have trained many home inspectors and certified chimney sweeps. I have found chimney sweeps know more about chimneys than most HVAC contractors.