Hot water flow switch pump / disable loop

[caseyjay]

Hi, my boiler is quite far away from my taps so someone installed a Grundfos pump to speed up the flow. When on, it all works fine but found that if left on for 20 mins or so, all the hot water (200l tank) goes.

I guess this is because there is a loop back to the cylinder and the cycle is losing its heat.

The simple answer appears to be turn the pump off when not needed - trouble is it's in the cellar, and a pain during the winter.

So I am looking at swapping out for a flow switch pump which will work on demand. Would I then be best cutting off the loop as well?

Appreciate any advice.

 

[Mark Br]

Put the pump on a timer

 

[caseyjay]

if I were regular as clockwork for needing hot water every day then the timer would work. As I'm not, the pump would then be running when I don't need the water and as it's on a loop, I fear it's losing all its heat running around the system - hence the only on demand query....

 

[twgas]

what about a pipe 'stat, turn off loop/pump once it's hot, lag the pipe to keep the heat in and it will not come on too often.