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.

Gas hot water tank instead of boiler????

tessy
tessy Member Posts: 2
im in the planning stages of remodeling my basement for living . the old floor will be removed to dig down for more headroom( i will be doing the work ;concrete contractor). ive poured many floors, garages, sidewalks, driveways,etc with the radiant heat and even installed the tubing but have never had exp. with the final connections...anyway..

1st--- question is can i use a HWT to run the system????

-the basement will be 975sq.ft

2nd--- is can i use the same system to heat my future de-tached garage ??

-the garage will be 675sq.ft. so a total of 1,651sq.ft.

the reason i ask is that i have a 60 gallon gas power vent tank that is brand new ....

Comments

  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    Not to code in Massachusetts

    Some places let you but not where I am. The heater needs to be rated by the manufacturer to be a space heating appliance.
    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
  • tessy
    tessy Member Posts: 2
    RE.

    thanx charlie for the response..

    i was told at a local plumbing supply that using 1 would be a slightly cheaper option....now i guess i took that as it must be legal, but i will have to check..

      what are the pros and cons to a system like that??? obviously i wouldnt think it would be as efficient??!!!

    also as far as running lines to the garage ...

    i would have to get the insulated pre wrapped tubing correct?

    1 other question is that i remember some1 saying that the btu per sq. would be less than that of a boiler ???

    any opinions on this design im open for suggestions....

    thanx every1
  • gennady
    gennady Member Posts: 835
    water heater as a boiler

    To the best of my knowledge, boiler is a device with outlet temperature over 140F and must have H stamp. If outlet temperature is lower than 140F, then it is a water heater, and do not have H stamp and is not a subject of boiler code and boiler inspections. How you use it does not matter
  • meplumber
    meplumber Member Posts: 678
    It does in some jurisdictions.

    Gennady, in some jurisdictions, a duly licensed professional cannot install a water heater as a central heating appliance.  It has less to do with the water temperature and more to do with the H stamp and the relevant safety devices.  Also, the AHJ's are reluctant, as the number of homeowner installed units try and pull DHW and heating from the same water path increases.  This has huge legionnaire's potential and I believe there have already been some cases documented.



    From an efficiency standpoint, there are better options out there than a unit designed to provide domestic hot water.
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,216
    Pressure is different too

    The pressure relief for a water heater is 150 pounds. The heating components are rated for a 30 pound relief valve to be connected. This means after several years of service some knucklehead comes and replaces the 30 pound relief valve with a 150 pound relief valve and the thing to pop is the radiator piping in the bed room or bath room not the pressure relief valve. Codes are for herding the knuckle heads.
    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
  • gennady
    gennady Member Posts: 835
    water heater as a boiler

    Well, i meant instantaneous water heater, and also i meant it is possible, but it is not right thing to do. I would never advise to customer to do it,but i'v seen it done and it works just fine in radiant heat application. Of course local regulations must be followed.
  • Dan0
    Dan0 Member Posts: 3
    works for me

    I have a 24 x 40 / 960 sq ft garage that I heat with a  40 gal, Nat gas water heater, I keep the temp at 55 to 65 deg depending on what I am doing, I poured 5 in of concrete with a 12 in bell footing, plastic & 1in of foam under that, 4 rolls of 1/2 in Pex, 4 zones equally heated, I also just installed staple up with aluminum heat panels in my home, 1708 sq ft, also use a 40 gal DWH for that, total sq footage for both is 2666 sq ft with 2 hot water heaters, I use on avg of 7 therms per day, at a cost of .885/therm or $6.19/day, that includes my water heater for the house, gas dryer & forced air furnace for back up, for a family of 4, I live in S/E Wis & keep the inside temp of the house at 70 deg, the house is 20 yrs old & I am in the process of sealing up minor drafts & cold spots & watching my gas bill drop :-)
  • Gordy
    Gordy Member Posts: 9,514
    edited February 2011
    It may work

        But just think if you had a mod/con doing the heating what your gas bill would be with a 93% eff boiler. Not to mention more space with less tanks around. Also the possibility of never needing the FA system as a back up because you could supply higher water temps to the staple up zones than a water heater can supply.



    Gordy
This discussion has been closed.