c/h on puma 80 stays on

[bourkey]

can anyone help
we have got a puma 80 about 5 years old c/h comes on by itself but cannot be turned off by timer or switch,hot water is fine,red light comes on
when tap is running.only way to turn c/h off is to put boiler on stand by.

 

[kevplumb]

dhw flow switch is stuck

 

[ChrisR]

Your domestic hot water flow switch is stuck in the "flow" position. Do a search on Puma, DHW flow, etc and all will be revealed.

 

[bourkey]

will check dhw flow switch cheers thanks for a speedy reply