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Need help with heating & hot water setup for tight space

Hi. I'm new to the forums here. I am in need of some help/input, any feedback is MUCH appreciated.

My situation:

- 1200 square foot condo apartment in Brooklyn, NY. On 2nd floor of a 4 floor building. Major heat loss is 2 exterior walls, all other walls touch 'warm' living spaces.

- Boiler closet within apartment is 36" wide, 31" deep, 7' high.

- Gas connection

- Current setup is a wall mounted atmospheric boiler. 100,000 BTU. Made by Myson, Apollo model. Completely dead now. Domestic hot water is from an indirect tank, 36 gallons. Made by Crown. Only 2 years old, still works fine. I'd like to keep/reuse the indirect tank if possible, will replace if I have to.

- Nobody makes a wall mounted atmospheric boiler these days. They don't exist. All wall mounted boilers have to be direct vented. I can't install a direct vent. So I have to use a normal cast iron floor boiler.

- I can't find a boiler + indirect tank combo that will fit within the tight space constraints I have. I've been looking at a bunch of 80-100,000 BTU boilers, none are small enough to fit along with an indirect tank.

- I can't install the indirect tank above the boiler, the walls are not strong enough to support it.

- If I can't fit an indirect tank along with a new boiler on the floor, I'm considering an external tankless coil. There's one made by TFI EverHot: <a href=""></a>. I'm looking at the 4 GPM or 6 GPM, which are small/light enough to fit in my boiler closet along with a new floor boiler. Does anyone know this company? Are they reputable? Will these units really deliver that amount of domestic hot water output? If so, for how long?

- I realize the external tankless coil solution is not the most energy efficient. It will also require an additional circulator pump, and I'll probably want a priority valve for when the heating system is on AND I need hot water at same time. The units don't seem to be insulated very well, I'm concerned about the heat loss and constant firing of boiler to keep the tankless coil hot. So all in all, I don't love this solution. But I can't find another option. Or is this option not so bad in reality, and I should just accept it?

Like I said, any feedback and suggestions are MUCH appreciated. I've been stuck with no hot water for 1 week already, I really need to find a solution and have it installed.




  • Robert O'Brien
    Robert O'Brien Member Posts: 3,425
    How about?

    How about an Energy Kinetics? They make a stackable gas model that will fit your parameters
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • CMadatMe
    CMadatMe Member Posts: 3,085
    Heat Loss

    No way you need 100,000 btu/hr is heat that space. You have no loss above and below. Does the existing boiler vent into a common chimney or is it its own?

    If common how about. Burnham Series 3 of appropriate size, it's 33" deep and much slimer.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Slimpickins
    Slimpickins Member Posts: 323
    Alllied Space Saver Combo

    I used an Allied Space Saver Combo in a situation like  yours.. Chris is right about 100k being too big. Do a heat loss calc and go from there. The piping instructions are weak in the manual but must be done in primary/secondary or you'll get a low flow harmonic noise. Good luck!
  • Kevin_in_Denver_2
    Kevin_in_Denver_2 Member Posts: 588
    Everhots work great

    I see these all the time in multifamily boiler rooms. Many are original, 40-55 years old.

    Paired with an efficient boiler, I think they are a good space-efficient solution.

    I'll bet you can find a good professional in the area who uses something like a Rinnai wall-hung tankless water heater as a boiler. Careful... it takes experience to do it right, but some cities allow it.

    Michael Chandler has done it many times:
    Superinsulated Passive solar house, Buderus in floor backup heat by Mark Eatherton, 3KW grid-tied PV system, various solar thermal experiments
  • kcopp
    kcopp Member Posts: 3,900
    To get you....

    by you could install a small electric for your domestic  while you sort out the details.
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