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can you use a instant hot water heater to run a baseboar loop

Timco
Timco Member Posts: 3,040
in THE MAIN WALL
Rinnai is absolutely rated as a heat source, and there are many piping options to accomodate your DHW with the same unit as well as hydro-air units. Check out their website. Great stuff and really easy to maintain...just be sure to perform regular maintainance (clean) the HX....the gas valve is fully modulating. Also, be SURE to use a x-tank and a 30# relief valve...NOT the T&P the unit will likely come with....

Tim
Just a guy running some pipes.
celestedorage

Comments

  • Garrett
    Garrett Member Posts: 2
    can you use a instant hot water heater to run a baseboar loop

    i am doing a pretty small loop of baseboard at the max i would need 70,000 btus to do it all comfortably, i heard there is a rinnai that can be used as a small boiler, has anyone done it?
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,519
    Do you mean a Tankless Water Heater???????

    Many folks confuse the two. Mad Dog

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
    Consulting by Mad Dog & Matt Jr.
  • Garrett
    Garrett Member Posts: 2


    yes i do mean a tankless water heater, can it be done
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    yes.

    just don't use the same tankless do do your domestic w/o seperating the waters. Plumb it like you would a normal boiler.
  • amhplumb_2
    amhplumb_2 Member Posts: 62
    Tankless Water Heater/Hydronic Heating Use

    Research this further with your supplier, but I seem to remember from a Rinnai class that the warranty changed if it was used for hydronic heating.
  • Mike T., Swampeast MO
    Mike T., Swampeast MO Member Posts: 6,928


    70,000 btu doesn't really sound "small" to me.

    Tankless water heaters are designed to greatly raise the temp of a small amount of water while boilers are designed to (by comparison) lightly raise the temp of a large amount of water. Try to move a lot of water through a tankless in order to pack in those BTUs and many will have extraordinarily high head loss requiring a very high-powered (and energy hungry) circulator, and I'm not even touching on the greatly increased velocity inside the HX. Study manufacturer literature very carefully before using.

    Plenty of "real" boilers (both conventional a condensing/modulating) that are reasonably suited to such a loss.
  • Derheatmeister
    Derheatmeister Member Posts: 1,581


    Do not be cheep just buy a boiler.

    Instand waterheaters are based on setpiont not Outdoor reset!

    Seen to many problems with these kind of installs!
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