Water into F/E tank

[davidstanton]

I fitted a new pump to my old Glow Worm 65 80-B. It's a balanced flue, pumped downstairs, gravity upstairs system.

Having fitted the pump, I am regularly getting excessive water going into the F/E tank in the loft, and then overflowing. This is only happening when the CH is on.

I have been given two possible solutions:

One said turn the pump speed DOWN as the new pump will be more efficient than the old pump and may be "over pumping", and the other solution was turn the pump speed UP do dissipate the heat quicker, reducing over heating and expansion on the F/E tank.

Any ideas? Thank you

 

[chrishutt]

Since the feed and expansion tank is overflowing when this happens, your problem is more serious. You probably have a blocked feed pipe near the connection to the circulation pipes (very common - do a search here for lots of threads on this).

 

[davidstanton]

Would that be the case eventhough the boiler / system drains completely and fills perfectly from the F/E tank?

 

[murdock]

Have you fitted the pump the right way round?

 

[davidstanton]

I assume so, as I fitted it the same way round as the old pump

 

[JohnD]

One said turn the pump speed DOWN as the new pump will be more efficient than the old pump and may be "over pumping"

have a look at the position of the F&E pipe, and the expansion pipe. they should be close together, and on the "suction" side of the pump (which will likely have an arrow somewhere on the casing to show direction of flow.

That ought to mean that excessive power in the pump will not be trying to push water up the pipes, as it might if they were on the pressure side, though you might possibly get a momentary surge when the pump starts.