Pumped Feed to Hot Water Tank and Diameter of Pipework All aspects of plumbing questions and answers, help, tips and information

[billy-b]

I am in the process of fitting radiators and pipework ready to have a boiler fitted. I have a gravity fed hot water tank which has a solar panel heating with an immersion heater for top ups in the winter and it also has two auxiliary heating coils, I wish to feed one of these coils from the boiler instead of using the immersion heater. Whilst I accept that 22mm pipes are required if heating the tank by gravity, is it ok to use 15mm from the boiler pump. The tank is probably about 5 metres from the boiler

[proptech]

Hi billy-b
22mm should be used for this, remember to include a balance valve on the return. For a gravity system 28mm would be used.