I’ve recently had a mixer shower fitted that runs off my hot water/central heating boiler.
When I run the hot tap at the wash basin I can hear the burners light up and it delivers hot water continuously.
When I run the shower it gives hot water for maybe 3 minutes ,then the burners stop and cold water comes out.
If I leave it running ,after maybe a minute or two the burners light and hot water comes again, and so on till I’m finished showering
