baxi 80he dhw-dials-?

[pistonpat]

have the baxi instant.the problem is if. i run the hot water nothing happens-if i turn the preheat tap dial up and down it will work --
but sometimes the light will flash =(warm). sometimes fine
(the heating works fine)

 

[Cpplumber]

The preheat is there to heat the secondary heat exchanger to allow instant hot water. If you have this feature off, you will have to wait a short time for the boiler to start heating water and a few additional litres of water. Most people don't bother with the preheat as the boiler fires randomly to do this. You turning the dial up and down is probably just activating this as it should do.

The fact it doesn't fire when you run the tap suggests either a flow sensor or diagprahm in the diverter valve is at fault. I'm not 100 percent on the boiler you have to point you at the fault. I'd suggest getting a RGI out to look. Should be a relatively easy fix once the fault has been dialled in

Good luck.

 

[pistonpat]

strange i just turned the main water from the stopcock outside and it seems to be working fine