hi! i have a hot water baseboard weil-mclain oil fired boiler about 20 years old,i noticed for some time now that my circulator will come on for a few minutes before and burner comes on,but never does the circulator pump stay on after the burner shuts off as it should and like it did in past,could this be in the temperature gauge.i also get my hot water from the boiler as well.thanks for any help. bill
The thermostat calls the relay that runs the circulator. When the temperature drops below the set point of the aquastat the burner then runs. Domestic hot water is controlled by the low limit aquastat which maintains it's set point ( usually about 160 ) Unless it's not heating or you are not getting enough hot water it's operating fine.
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