Hi Guys - A bit of advice required

[Jagobezzer]

Hi Folks, I need a bit of advice or help.

I have a low pressure hot water system due to the Hot Water Tank being in a bedroom, not in the attic. I have a Salamander Electric Pump fitted, which until recently has now started "hunting". It's driving me banana's as I was told by Salamander to:

1. Switch off the pump at the electric point
2. Close the inlet valve (only two valves on this pump - in and out)
3. Run the water through all the taps using the pump, non comes out due to the inlet being closed.
(I have tried to run just water through the entire system without the pump running)
4. Use a foot or bike pump to pump the pressure vessle to 29-30psi
5. Open the inlet valve and then switch on the pump.

No difference?

The thing is, the pump operates normally when running the hot water tap on the bath (22mm copper pipe) but hunts on the 15mm copper pipes that supply the bathroom sink upstairs, kitchen sink downstairs and the wet room sink downstairs.

I can only guess that there is an air bubble in the system which is compressing when the pump runs causing it to hunt.

Any help or even paid assistance would be greatly appreciated.

All the best
Jim

 

[ShaunCorbs]

Or the pump is getting old and the pressure transducer is starting to fail causing it to come on when it thinks there’s a pressure drop

Or you have a leak etc

 

[John.g]

The precharge pressure of 30 psi seems a bit high even though it shouldnt cause a hunting problem, think I pumped one up for someone (pump was cutting in/out frequently when off) to ~ 10/12 psi. May be worth throttling in that bath hot tap until or if the pump starts hunting and measure the flowrate then, I think these pumps also use flowswitches to stop the pump when the flowrate is < 1.0LPM and the pressure switch is satisfied although hunting is not a sign of start/stop operation.