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Gas gun versus new gas boiler

silow
silow Member Posts: 1
We're converting from oil to gas as part of a renovation that added a room and expanded another room in the house. Our Peerless oil burner is only 5 years old. One option is to get a gas gun for the current oil burner, which our plumbing/heating contractor says should have enough capacity but 'it will be close.' The alternative is to replace the boiler with a slightly higher capacity gas furnace. Any suggestions?

Comments

  • KC_Jones
    KC_Jones Member Posts: 5,081
    edited August 2016
    silow said:

    We're converting from oil to gas as part of a renovation that added a room and expanded another room in the house. Our Peerless oil burner is only 5 years old. One option is to get a gas gun for the current oil burner, which our plumbing/heating contractor says should have enough capacity but 'it will be close.' The alternative is to replace the boiler with a slightly higher capacity gas furnace. Any suggestions?

    Has a heatloss been done? That is the only way to determine the size of the boiler that is needed. It is also the only way to determine how much emitter you need in the addition. Why would you completely switch to forced air for a gas conversion?

    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • ChrisJ
    ChrisJ Member Posts: 12,819
    If the boiler is big enough now, why won't it be after the conversion?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Robert O'Brien
  • SWEI
    SWEI Member Posts: 7,356
    I'll just add that it's quite likely the existing boiler is itself oversized. Assuming the block is still in good shape, a gas gun can often be sized (down) and tuned to the heat loss, which can increase the efficiency of the boiler.
    EzzyT
  • Steamhead
    Steamhead Member Posts: 15,329
    Is this a steam or hot-water system?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    Charlie from wmass
  • SWEI
    SWEI Member Posts: 7,356
    Good point...
  • ChrisJ
    ChrisJ Member Posts: 12,819
    Do boilers produce less output when converted with a gas gun?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    The efficiency is 2 percent lower with the same rated input btus with gas vs oil. So yes it can be lower. It often is a none issue as the boilers are usually slightly to grossly oversized. If this is the case they can be downfired to the required output rating and you gain back some efficiency points.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
    SWEIChrisJ
  • ChrisJ
    ChrisJ Member Posts: 12,819
    2%?
    What is that, 1000-2000 btu/h on the typical boiler?

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Charlie from wmass
  • Paul48
    Paul48 Member Posts: 4,469
    Has there been any mention of a chimney liner? If you add that to the equation, it might be time to look at a mod/con. It's an option, a great option, when handled by a highly competent HVAC contractor. Handled by a contractor that only matches the capacity of what is already in the house, it can be a nightmare.

    I guess we need to clarify something......Is this hot air, water, or steam?
    Charlie from wmass
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,450
    If it's not steam, the smallest Peerless oil boiler is 3x larger than the average NYC area homes heat loss
    To learn more about this professional, click here to visit their ad in Find A Contractor.
    Charlie from wmass
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    Also peerless says a. Gas conversion voids the warranty.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ChrisJ
    ChrisJ Member Posts: 12,819

    Also peerless says a. Gas conversion voids the warranty.

    So void the warranty and if the boiler fails 5-20 years from now spend the money on a new one at that time. No?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    It is not my choice, every homeowner needs to weigh that for themselves. But if this is hot water Robert's point stands, the boiler is too big.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
  • ChrisJ
    ChrisJ Member Posts: 12,819

    It is not my choice, every homeowner needs to weigh that for themselves. But if this is hot water Robert's point stands, the boiler is too big.

    I don't know if anyone can say that without seeing a heatloss done on the house.

    We don't even know what size it is.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    I can, I asked the magic 8 ball. Lol
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
    ChrisJZman
  • njtommy
    njtommy Member Posts: 1,105
    @ChrisJ too big is the size. How many times have we ever seen a house or at least posted on here being too small of a boiler. I can personally say 2 times in 12 years I've seen a system that was too small.
  • Steve Minnich
    Steve Minnich Member Posts: 2,755
    I've seen plenty of undersized AC's but not any boiler that I can remember
    Steve Minnich
    Minnich Hydronic Consulting & Design, LLC
    [email protected]
    njtommy
  • Paul48
    Paul48 Member Posts: 4,469
    That's because guys won't admit when their unit is too small. :wink:
    ChrisJCanuckernjtommySolid_Fuel_Man
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    edited August 2016
    Albany NY is the home of undersized steam boilers. Most of the problem boilers I see there are undersized if they are under 10 years old.
    Has the OP answered iif it is steam or hot water?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    https://heatinghelp.com/find-a-contractor/detail/charles-garrity-plumbing-and-heating
    njtommyZman
  • ChrisJ
    ChrisJ Member Posts: 12,819
    njtommy said:

    @ChrisJ too big is the size. How many times have we ever seen a house or at least posted on here being too small of a boiler. I can personally say 2 times in 12 years I've seen a system that was too small.

    My house had a Burnham V83 connected to 392sqft of radiation when I moved in.

    Oddly enough, the V83 outputs something like 63,000 btu/h I think? Which is just about right for the house's heatloss.

    Sadly, that's not how any of this works with steam. :)
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    Charlie from wmassnjtommy
  • jumper
    jumper Member Posts: 1,830
    My experiences in the seventies & eighties are like njtommy's. Generations ago local authorities ordered too big heating systems. Then in the eighties they insisted on marginally sized replacement boilers and furnaces for those over sized systems in the name of energy efficiency. Rarely a problem in Toronto where those design condition cold snaps don't last long. Other places can be different.

    njtommy
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,450
    ChrisJ said:

    It is not my choice, every homeowner needs to weigh that for themselves. But if this is hot water Robert's point stands, the boiler is too big.

    I don't know if anyone can say that without seeing a heatloss done on the house.

    We don't even know what size it is.
    I've never seen an undersized hw boiler in 38 years. The smallest Peerless oil is 129K. I stand by my statement
    To learn more about this professional, click here to visit their ad in Find A Contractor.
    njtommy
  • Tim McElwain
    Tim McElwain Member Posts: 4,506
    What is the Make Model and Serial number of the existing boiler? Was a heat loss done when the oil boiler was replaced?

    A gas conversion burner can if properly set up and the unit fired to its maximum design efficiency be equal to the oil gun if not a couple of percentage points above.

    My experience (over 3,500 gas conversions in my career) on converting most Peerless boilers has always been good. I never worried about warranties as i picked up the warranty myself.
  • captainco
    captainco Member Posts: 595
    Yay Timmie!! A comment based on experience and confidence rather than opinion and insecurity. What Timmie says is absolutely solid. :D