Isaac Occhipinti, head of external affairs at the HWA, said: “HWA member companies receive enquiries from both consumers and installers on a regular basis, asking for help and advice on sizing the hot water cylinder. The HWA wanted to make this process as easy as possible for everyone, and so we have developed this online tool. 

“Getting the calculation wrong can have repercussions for everyone involved: installers get called back to jobs; consumers run out of hot water or pay over the odds heating water they don’t use; and manufacturers get called out to unhappy customers.

“The good news is that answering a few questions on our new online cylinder sizing calculator will help consumers identify the correct size for the job.”

Stuart Elsy, commercial group chair at the HWA, added: “The cylinder sizing calculator has been created using government and heating design guidelines, together with decades of experience from water heater manufacturers, to give consumers and installers logical and sensible advice on the size selection of a domestic hot water cylinder.”

Should a property require a unique type of cylinder, HWA members can also offer advice on bespoke solutions.