I have a Myson Apollo 15kW boiler with just a two position HI-Low temperature switch. It does not matter which position the switch is in, the flow temperature at the boiler never gets to more than 55degC (measured with a clip on thermometer). I turned the CH thermostat way up to 30degC, to make sure that it was not switching the boiler off, but it made no difference. The house got hotter (very) but the pipe temperature only crept up a few degrees and the boiler just ran and ran without cutting out.
I wondered if it could be that the pump is set to high (Grundfos Selectric 15-50 set to speed 3). The boiler installation instructions say that the pump must be able to deliver 1.145 cu metres/hour at a head of 3.35 metres, which the pump can do (just) on speed 3. So I am reluctant to turn the pump down in case it damages the boiler.
Does any one have any thoughts or suggestions as to how I can get the boiler running at a higher temperature?
I wondered if it could be that the pump is set to high (Grundfos Selectric 15-50 set to speed 3). The boiler installation instructions say that the pump must be able to deliver 1.145 cu metres/hour at a head of 3.35 metres, which the pump can do (just) on speed 3. So I am reluctant to turn the pump down in case it damages the boiler.
Does any one have any thoughts or suggestions as to how I can get the boiler running at a higher temperature?