Heating boiling over tank out of expansion tank vent.??

[fula28]

Well WE have a boiling over imersion tank via loft vent!!! it filled the loft and upstairs with steam so shut it down. Its an old glow worm boiler with no separation between the hot water coming on and heating no elec, valves here. The fault like i say is heating on boils the hot water tank? maybe indirect pipework in tank U/S leaking into hot water tank? thats what ive been told so far. There is a valve on lower part of the imersion tank with D 1 2 on it is this the priority valve? pos u/s sorry bit new to this kinda work. any ideas .thanks

[stoneyboy]

fula28,
Suggest you get a gas man in to check the boiler thermostat and the boiler.
end

[Ronald0]

What controls the temperature of the hot water cyclinder when it is being heated by the boiler?

Does it have a thermostat attached to the side which is connected to to boiler? Or do you regulate the hot water temperature by the boiler thermostat?

[Tuesdaywhistler]

This is a very dangerous situation and I strongly suggest you get a proffessional in to have a look.

Tuesdaywhistler
Gas Safe Registered Engineer