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Oil Boiler Heat Help

abdool3002 Member Posts: 2
I’m hoping someone can advise me on how to proceed with my heating problem. My wife and I recently purchased our home that has a 12-14 year old Oil boiler with baseboard heating. Everything seemed fine during the winter/spring months but lately we’re noticing the boiler switching on by itself and sending heat to the baseboards. Initially we thought maybe the thermostat was bad, since it looked very old. We replaced the thermostat hoping that would solve the issue but it doesn’t seem as though it did. The boiler is also used to provide hot water in our home. Any advice would be appreciated.

Thank you.


  • Paul48
    Paul48 Member Posts: 4,469
    It is most likely convective flow. There should be a flow control valve(s) in line to prevent that. Perhaps there is and it is stuck open. Some pictures would help us, help you.
  • Jamie Hall
    Jamie Hall Member Posts: 18,923
    To add to @Paul48 's comment -- the boiler is most likely switching on by itself to maintain the hot water hot, since it also supplies the domestic hot water to your home.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • abdool3002
    abdool3002 Member Posts: 2
    Thank you all for the comments. @Paul48 @Jamie Hall I will provide some pictures this evening and try to locate the valve.
  • captainco
    captainco Member Posts: 595
    As Jamie said, your boiler is making hot water. And as Paul said this heat is somehow getting to your radiators. Could be a pump problem or a flow problem. The boiler has its own temperature control to come on for hot water. The control is probably on the storage tank.

    There really haven't been many improvements in oil boilers in the last 16 years and many of the changes made have not been beneficial other than making them cheaper to produce.

    Using an oil boiler to make domestic hot water in the summer is expensive and possibly more expensive than an electric water heater. Plus, it is adding a considerable load to the A/C system if you are in an area that needs it.
    EBEBRATT-Ed Member Posts: 11,989
    Most likely suspect is your flow control valve is leaking buy during summer operation allowing water to enter the your baseboards by gravity flow
  • newagedawn
    newagedawn Member Posts: 586
    could be a short in your low voltage wiring,turning on your circulator to flow water through the baseboard , is your t stat wire old and in knots?
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"