Gravity to pumped hw

[bellmanplumb]

I have just been to look at a house that initially looked to be an old gravity hot water and pumped c/h system. The cylinder was changed last summer (not by me), and since then the header tank has run over when the boiler is on for hot water. After a lot of mucking about I found in another very small loft space, that the cylinder changers had fitted a pump on the hot water side wired through a relay. So this was literally just pumping the water up and over into header. I have disconnected the pump so in essence we are back to a gravity system but was wondering if there was any other way of getting a pump back onto the hot water side easily enough? The pump is located by the boiler and the c/f and ex are by the cylinder approx 7 metres away.
Any more info needed let me know.

Thanks in advance

 

[diamondgas]

bellmanplumb ...... You'll struggle to put two pumps on an original gravity / pumped heating without the symptoms you describe... Is the boiler original or relatively new? Reason I ask is regarding the ability to seal or combine f&V 🙂

 

[bellmanplumb]

boiler is probably nearly 30 years old at a guess!!!

 

[diamondgas]

Is the pump on the flow by any chance? If so it shouldn't be because it may well be interrupting the free path required for the openvent! In theory you could fit a pump with a bypass. The bypass would in effect reduce the flow and pressure put on the open vent/feed pipes. I say in theory because I've never seen it done? 🙂

 

[bellmanplumb]

no pump is on the return. I think I may have to take the pump out completely and leave them with a gravity system again and suggest this summer is a great time to look into updating the boiler!!

 

[diamondgas]

no pump is on the return. I think I may have to take the pump out completely and leave them with a gravity system again and suggest this summer is a great time to look into updating the boiler!!

Is there no way of converting to 'y'plan?