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Maintaining 110 degree minimum in standard boiler (no water tank)

ehhorn Member Posts: 1
edited March 2019 in Oil Heating
During our annual boiler service the tech suggested replacing the control so the boiler would maintain a minimum 110 degree core temperature. His reasons were: 1- the boiler (cold start oil) wouldn't have to recover from a much lower temperature, reducing the amount of soot build-up in the combustion chamber, and 2- resulting in better heat transfer through the boiler jacket. The boiler does cool off to ambient basement temperature (45-50) during the day primarily because the house shell is well insulated and has sufficient insolation to keep the house's living space warm. Can I expect the oil burned to maintain the minimum 110 temperature be offset by the improvement in efficiency?

Thanks for your responses!


  • STEVEusaPA
    STEVEusaPA Member Posts: 5,966
    Nope. Sounds like your boiler is very oversized, or you are using deep setbacks.
    Your better off with an aquastat that helps keep the boiler from condensing, via circulator hold off, or proper piping to keep low temperature return water out of the boiler. Doing so will allow the boiler to heat up quicker, and get you out of condensing quicker. Sustained condensing in the flue and the chamber contribute to soothing.
    A properly cleaned/tuned burner, with adequate combustion air won’t soot up. I have one particular customer with a cold start Peerless I service every 2 years (because he won’t go 3). Virtually no soot.
    I haven’t cleaned my boiler in 3 years. Swung open the door, nothing to clean. Changed nozzle, dual filters, pump strainer, combustion test.
    Warm start will just waste fuel.