Cold Radiators Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[woodie]

When I used most of the hot water ie for a bath and then the boiler comes on to re heat the water my radiators go cold. If I switch off the hot water my radiators go hot. It only seems to happen when I use a lot of hot water.

[roger196]

Your boiler is setup to give priority to hot water. Only once it has reheated the hot water tank will it turn its attention to the CH.

[DONFRAMAC]

Combi boilers are designed to do just that,---- hot water priority, diverter valve returns flow to rads only after hot water demand is finished.

[woodie]

Thanks for info. Had system for awhile never noticed it before.