H/W entering F&E tank through system feed pipework? Any

[Plumbhelp]

Hi,
I have an open vented system which feeds a cylinder and boiler. When the boiler is operated the pump seems to operate but the hot water is also backing up the supply pipe from the boiler back to the F&E tank which is then pouring out the over flow pipe. The pump was changed recently, I have changed the stat on the cylinder. My next two steps would be to change the stat on the boiler (glow worm hideaway) or check if the cylinder is split inside. Is there an easy way to check this or could this be something else. Any help/advise is greatly appreciated.

Many thanks
Paul

 

[dcawkwell]

Nothing to do with any of that.
Sounds like you have blockages in the system.

 

[petertheplumber12]

Or may be caused by the pump being put on the wrong way round, make sure the flow pipe on the boiler is the pipe that gets hot first when boiler switches on.

 

[Plumbhelp]

Thanks for your replys.

In regards to blockages do think the system needs a power flush? The 3 rads on that level heat up ok.

I will also check the pump but it doesn't seem that it's being pumped into the tank just backing up from boiler when operated.

Need to get this sorted.

Cheers

 

[dcawkwell]

Cap the feed and expansion pipes and shove some mains pressure through the system.

If possible go to a sealed system at the same time. If your boiler has a overheat thermostat. Open vented systems have no place in a modern heating system.

Sorted.