Please can someone advise.
Baxi 105e combi.
New pump fitted 6 months ago
New diverter valve fitted 3 months ago
Magnetic filter and additive fitted.
On the top of the diverter valve there is a diaphragm. Some call it a pump proving switch others call it central heating diaphragm.
Anyway, boiler works fine on both hot water and heating, on first fire up. The problem is once you turn off the hot tap or heating reaches temperature and shuts it down, the pin that operates the micro switch doesn't retract fully ready for next demand of heat or hot water, so the boiler won't start and the 60° led flashes indicating air in the system or low system pressure. I changed the auto bleed valve when I changed the pump. Boiler is quiet so not air, and pressure is good 1.5 bar cold.
I've just removed the top diaphragm all is clear, cleaned and silicone grease gland and pin. The drilling below the diaphragm is clear and the copper line out the back to the bypass pipe is also clear. Still the same.
If I manually push the pin down after each cycle it works fine until next time it reaches temp on heating or hot tap is turned off then the pin fails to retract again, 60° led flashes.
I know it's an old boiler but any ideas?
Baxi 105e combi.
New pump fitted 6 months ago
New diverter valve fitted 3 months ago
Magnetic filter and additive fitted.
On the top of the diverter valve there is a diaphragm. Some call it a pump proving switch others call it central heating diaphragm.
Anyway, boiler works fine on both hot water and heating, on first fire up. The problem is once you turn off the hot tap or heating reaches temperature and shuts it down, the pin that operates the micro switch doesn't retract fully ready for next demand of heat or hot water, so the boiler won't start and the 60° led flashes indicating air in the system or low system pressure. I changed the auto bleed valve when I changed the pump. Boiler is quiet so not air, and pressure is good 1.5 bar cold.
I've just removed the top diaphragm all is clear, cleaned and silicone grease gland and pin. The drilling below the diaphragm is clear and the copper line out the back to the bypass pipe is also clear. Still the same.
If I manually push the pin down after each cycle it works fine until next time it reaches temp on heating or hot tap is turned off then the pin fails to retract again, 60° led flashes.
I know it's an old boiler but any ideas?
