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Venting Installer Question - Can I Use One Trade?

njb52njb52 Member Posts: 11
We will be replacing our existing over sized boiler with a new higher efficiency boiler and want to reuse out existing chimney flue to vent the exhaust. Since the new boiler will produce lower exhaust temps, it was recommended that we use a 4" liner for the existing flue with 4" B-vent between the boiler and chimney. Can a heating contractor/plumber do the new liner and associated duct work install, or would I need a chimney sweep to do that work and get separate pricing? It would be nice to have one trade involved so that if any future problems occur, the original installer can rectify them.
Thanks in advance.


  • Paul S_3Paul S_3 Member Posts: 1,257
    edited May 2016
    In my area we can .....where are you
    located....also make sure the new boiler is correctly sized .....what type of boiler cannot be 90%plus since your venting into high is chimney and what is the btu input of your new boiler?
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    [email protected]
  • njb52njb52 Member Posts: 11
    Thanks for such a quick response. We live in Massachusetts, and will be installing a Burnham or Weil McLain basic cast iron boiler. The preliminary sizing is for a 50K unit.
  • BmeBme Member Posts: 3
    Along those lines, I replaced my water heater today, as the tank started leaking. Went to my local home improvement store with a smart phone full of pictures so I get the right unit. Eight hundred dollars later it's home and installed. Checked all connections, soaped gas line connection and away I go. About 5 minutes after I fired it up I noticed a smell of paint gassing or plastic melting. Sure enough the pvc vent pipe is getting soft. Anyone here see where this is heading. Now I have fully installed high efficiency unit, where an ultra high efficiency unit was. The pvc vent pipe is on a upward pitch of 1 inch every 10 inches on a 17 foot horizontal run. Here is my question? Can I replace my pvc run with a standard galvanized steel vent line in a similar way or do I have to plumb it vertically thru two floors of my home? Any imputed would be greatly appreciated. Joe.
  • JUGHNEJUGHNE Member Posts: 6,783
    Pictures of before and after would be helpful if we could see the installation.
  • BmeBme Member Posts: 3
  • SWEISWEI Member Posts: 7,356
    njb52 said:

    We will be replacing our existing over sized boiler with a new higher efficiency boiler

    will be installing a Burnham or Weil McLain basic cast iron boiler.
    These two statements appear to contradict each other.
  • AbracadabraAbracadabra Member Posts: 1,948
    edited May 2016
    SWEI said:

    These two statements appear to contradict each other.

    Makes sense if their current boiler is 70% efficient :)
  • JUGHNEJUGHNE Member Posts: 6,783
    edited May 2016
    This is for Bme........................
    I believe that your old WH had an inducer fan that used dilutation air to cool down the exhaust gases so PVC pipe could be used.

    Your new WH looks gravity vented, requiring 4" B-vent exhaust up thru the roof. Not PVC side wall venting.

    If these assumptions are correct you have a FIRE and CO hazard!
    This is as serious as a heart attack!

    Look at the instructions that came with your new WH, which is lower efficiency than the old one by the way.
  • BmeBme Member Posts: 3
    You are correct. 3 hr drive to get the right unit. Thank you.
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