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convert water heater to holding tank

hotheat Member Posts: 1
I am trying to convert a 75 gal water heater to a holding tank for a boiler system. Where can I get the piping to connect to the old water heater element holes? Everything I have tried does not fit correctly.


  • Larry Weingarten
    Larry Weingarten Member Posts: 3,389
    Hello, For most electric heaters, those holes are one inch thread. They may be straight rather than tapered thread, as the elements use a gasket to seal, but I've never had a problem making them water tight using one inch tapered pipe fittings. o:)

    Yours, Larry
  • GroundUp
    GroundUp Member Posts: 1,956
    What he said^^^. All I've seen are 1" straight thread as well, and 1" NPT will seal under residential pressures. A good anaerobic thread sealant definitely helps seal better than tape and dope IMO, I use Permabond LH150 or Loctite 567
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Are you referring to the square flanged elements? As has been stated, the round elements are 1" straight pipe thread.

    If they are square, have your local machine/fabrication shop make you some adapter plates. May even be able to get 1-1/4 FPT then!
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!