Hi,

we have such situation: heat pump is heating convectors in domestical property (water volume is about 100 Litres ). There is factory fitted circulateing pump installed inside heat pump, and for this small water volume it seems too big...as circ.pump gets hot and noisy (presure is ~0,5 bar). The sugested solution is to increase presure by installing buffer tank on return side before the heat pump, but what volume it should be ? The point is to reach 1-1,5 bar so the factory preinstalled pump will work at nominal conditions and will not be hot and noisy. Thanks

(Also notice : diameter of copper pipes - 22 mm, convectors - 16 mm )