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Oil Furnace Turns On

Eggie Member Posts: 2
I have turned off the thermostat for my heating system, which is an oil furnace.  The furnace also heats the water for the house.  Other than turning on when we open the hot water, the furnace also turns on periodically for short periods, even when the water is not running.  I do not have a hot water tank.  Is it normal for the furnace to turn on for no apparent reason?


  • billtwocase
    billtwocase Member Posts: 2,385
    you have

    a tankless heater in the boiler, and it has to maintain temp to supply hot water. Necessary evil in your case. Only way to end the constant short cycles would be to have an indirect water heater installed, and set control to maintain about 100 degrees.
  • Mac_R
    Mac_R Member Posts: 117
    Furnace turns on

    You need to be careful about turning down the temp on older boilers.  (Because it was just installed does not make it new.)  Most systems that use a coil to heat the DHW require a minimum boiler temp.  I would read the manual that came with the boiler to find out what that temp is.  I know the New Yorker FR-122 requires 125 min temp.  Your best bet is to replace the boiler with a high efficiency system that uses an indirect water heater.  If you are going to be in the house for five to six years then it is worth wile. 
  • Eggie
    Eggie Member Posts: 2
    Electric Heater

    I was thinking of installing an electric hot water heater and leave the furnace only for winter.
  • Steamhead
    Steamhead Member Posts: 16,476
    You won't like it

    Tankless coils and electric heaters are both expensive to run and don't produce that much hot water. Go with an indirect instead. This could be hooked up to your present boiler if you aren't ready to replace it yet.

    With an indirect, the boiler does not have to maintain temperature all the time. It only fires when the indirect or the house calls for heat.

    And some indirects have lifetime warranties. You'll never find that on any standard water heater.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
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