Hi, my baxi solo 3 pfl 30 goes onto 'overheat' if operating with just the water selected. if heating & water are both on everything works ok.
I've replaced both operating and overheat sensors, pump and mid position valve, bled the system and had an auto-bleed valve fitted.
Any ideas?
rgds
Tom.

Tom Wood, March 2007

This can happen if there is no circulation of the water. If you have a three way zone valve it should be Ok, but if you have a couple of 2 way valves there can be a chance that when the water in the tank reaches temperature and shuts the valve there is no means of circulating the water through the boiler, which then goes into overheat

Malcolm, May 2007

Its the gas valve solenoid. Change the gas valve.

George, April 2007

hi there check the pump overun is working the pump should run for at least 4mins after heating or water has stopped calling.
if the pump is not running the heat build up of water stuck in the boiler will cause the overheat stat to operate

brod, April 2007