Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Burnham V-74T oil fired steam boiler need new combustion chamber/insulation?

Dave_61 Member Posts: 309

We are purchasing a house that has a Burnham V-74T oil fired steam boiler. We had the boiler serviced and were told that the combustion chamber needs to be replaced.

We were told that the risk would be that we could cause damage to the cast iron with the damaged chamber and were quoted a price of between $400-500 to replace.

I was looking online and found the kits for about $80. Looks pretty straightforward. But then I read somewhere that if the boiler is wet base, the only thing truly needed is the target wall and there would not be a risk of damage.

Is this true for the model I have? I am presently not at the house to look at piping (we close in September). Is this a wet base boiler, or can it be piped in different ways? And is replacing combustion chamber optional?



  • lchmb
    lchmb Member Posts: 2,997
    It is in fact a wet based boiler. You can run it without a chamber for a short time in my opinion, but it will effect noise and efficiency. As far as doing it yourself, I would warn against it. You need to be able to clean out the existing chamber, properly install the new one (it's not as easy as it seems) and set up the combustion once done. Some things are just better left to the pro's..
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,505
    edited August 2017
    The V-7 is a wet base. You would want to install the entire kit. Then you'd want to confirm that the correct nozzle size is in use, and have the unit combustion tested.
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
    HVACNUT Member Posts: 5,829
    $80 is what you would pay for the chamber kit. Then what?
    Like the others said, it's not an easy job for a homeowner to handle. Your out of luck before you even start because you don't have a soot vacuum or brushes. It will kill your shop vac.
    The burner must be removed (no swing out door on the V7). The blast tube insertion depth probably has to be adjusted with the new front plate refractory. New burner flange gasket.
    Start up, combustion analysis, draft and smoke tests.
    Your paying for a job, not a chamber kit and the prices you got are reasonable.
    I recently posted on another thread that Google tells you the price for a part (the company will mark it up and rightly so), but they don't tell you the labor, experience and overhead to do a repair.
    Pay for it. Sleep soundly, and save the black snot for the professionals.
  • Dave_61
    Dave_61 Member Posts: 309
    Thanks guys. I will definitely call and have the pros do it. Sometimes these YouTube videos make things seem much easier than they are.
  • BobC
    BobC Member Posts: 5,477
    i agree that job is best left to the pro's. Keep in mind the V7 boiler series had problems because of suspect castings, mine lasted almost 16 years and many didn't last that long. Just make sure they carefully examine the block sections to be sure it has enough life left in it to justify the repair. I'd hate to see you spend that money and then lose a section of the block because of a leak the next season.

    If the sections are in good shape the repair is well worth the cost.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Steamhead
    Steamhead Member Posts: 16,827
    @Dave , where are you located? We may know someone who can help. Have you tried the Find a Contractor page of this site?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service