GSHP - I need help with making it as efficient as possible!

EricMears

ccbrowning said:

EricMears said:

Very likely the system is running due to 'thermosyphon' : i.e. the hot water from tank downstairs is lifting itself up and displacing colder water in the floors.  You'll only stop that if you can put a valve into the line.

We have a meter which shows just heating electricity usage and I checked 24 hours after changing to summer mode and it’s not gone up at all. Hope it doesn’t cause issues later. So maybe the installers did a passable job? lol

If it is indeed 'thermosyphoning',  it wouldn't use any electricity to move heat around the house.  However, if that results in the tank cooling down you can expect the heat exchanger to fire up which will use power.

ccbrowning

Thanks! You appear to be right - used 1 kWh overnight. I’ll have to check the timer settings to see if I can get it to do this during the day so it may use the solar power. 

EricMears

ccbrowning said:

Thanks! You appear to be right - used 1 kWh overnight. I’ll have to check the timer settings to see if I can get it to do this during the day so it may use the solar power. 

A 'proper' solution (which I ought to do but have never got round to  ) would be to put a solenoid operated valve alongside the main pump and use existing <pump on> signal to operate the valve then the valve's output to operate pump.

matelodave

EricMears said:

ccbrowning said:

Thanks! You appear to be right - used 1 kWh overnight. I’ll have to check the timer settings to see if I can get it to do this during the day so it may use the solar power. 

A 'proper' solution (which I ought to do but have never got round to  ) would be to put a solenoid operated valve alongside the main pump and use existing <pump on> signal to operate the valve then the valve's output to operate pump.

You'd be better off using a motorised valve with auxiliary contacts to eliminate thermosyphon rather than a solenoid. A solenoid valve requires current to hold it open or closed whereas a motorised valve just uses power when its operating.