DIY Doctor UK DIY Forums

hi

can you use the hot water from a combi boilder if there is no water in the central heating system.

just wondering as i am changing some rads and want to know if i can run hot water whilst doing it

the boiler is a ferrolli modena 102 if it makes any difference

thankyou

paul

No, most combi's work by a plate heat exchanger transferring the heat from the sealed heating water to the Domestic Hot Water.

Alot of people think the DHW is heated directly by the flames, this is not the case with most combi's anyway, there are some exceptions (not sure about your boiler).

If the system and boiler are empty, if you open a hot tap the boiler shouldn't fire up. But I have seen some that still do. This can cause extensive damage to the boiler.

If it's going to take a couple of days for you to carry out the work, you could l eave one radiator in place, and re-pressurise system - then you can use HW as normal.

htg