We have a rather ancient but working well oil boiler for hot water & central heating that had manual controls, a switch for the pump & a mixing valve to regulate the temperature of the heating water (mixes hot water from the boiler with the CH return.
Yesterday I decided to bring this into the 20th century by fitting a thermostat in series with the pump & leaving the mixing valve all the way open (to the boiler).
While this is working insofar as the pump stops & starts there is still hot water in the heating system & a couple of the first floor radiators get hot.
Is this conduction through the pump ? If so is it normal (I can't remember the gas system in our last house doing this) & is there anything that I can do about it ?
Thanks in advance
Yesterday I decided to bring this into the 20th century by fitting a thermostat in series with the pump & leaving the mixing valve all the way open (to the boiler).
While this is working insofar as the pump stops & starts there is still hot water in the heating system & a couple of the first floor radiators get hot.
Is this conduction through the pump ? If so is it normal (I can't remember the gas system in our last house doing this) & is there anything that I can do about it ?
Thanks in advance
