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Instantaneous vs Indirect

Dobber Member Posts: 91
 I am currently quoting a radiant job that the homeowner wants an instantaneous water heater (Bosch) as opposed to an indirect. He has one now and likes it and believes it will be cheaper to run than an indirect with the boiler.

 I have never been a fan of instantaneous water heaters but I'm not stubborn enough to give a customer want they want as opposed to what they need.

 My question is, is there any operating cost comparison studies out there that I can use to  show  customers?


If you don't have time to do it right, what makes you think you have time to do it over?


  • CMadatMe
    CMadatMe Member Posts: 3,085
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Robert O'Brien
    Robert O'Brien Member Posts: 3,392
    I too would lean toward indirect

    The local utility offers a rebate on indirects but not tankless? The indirect should last longer,need less maintenance and repair and IMO the operating costs are so close as to be neglible. Since the customer already has one,I'll leave out the quirks of DHW delivery with tankless heaters .
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • R Mannino
    R Mannino Member Posts: 434

    How about your take on that paper Chris, I have some beer to drink and don't have time! :')
  • CMadatMe
    CMadatMe Member Posts: 3,085
    In a Nutshell

    Drink to your hearts content! No savings, but ya get 5 cents a can or bottle..
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Canucker
    Canucker Member Posts: 703

    I skimmed the article but it appears that they compared stand alone natural draft WH to a tankless and found a long payback? That would make an indirect an even better option, unless I missed that part, no?
    You can have it good, fast or cheap. Pick two
  • gennady
    gennady Member Posts: 830

    Indirect tank allows to size boiler to heating load and decouple DHW load from heating load. And because of that there is no need to oversize boiler. Also, post pumping allows to use heat otherwise be wasted. Also peak of DHW might be a huge btu draw, and gas line has to be sized accordingly. Instantaneous heater representatives try to convince it is not true, but in my opinion it is a big factor.
This discussion has been closed.