Baxi: pump noisy and stays on permanently after boiler off

[James L]

I have a Baxi boiler supplying a stored vented hot water system (hope that helps).

One of the two pumps does not switch off after the boiler shuts down. Also this pump is noisy and rattles.

Can anyone offer any advice on both these problems.

Also, does anyone know why the system has two pumps?

Thanks

 

[Agile]

Sometimes two pumps are used as an alternative to motor valves.

Has this only happened as a fault or was it always like that?

You should be able to work out if its the HW or CH pump. Then see if a thermostat has failed or fallen off the HW cylinder?

Tony

 

[James L]

Thanks Tony.

The plot thickens. One pump appears redundant (i.e. never kicks in) and the other pump is for the CH and it must also be for the HW as that is working? The two pumps were always in place. There is a thermostat dial on the cylinder but it appears fine.

The one pump continues to clank away. I have tried fiddling with the central knob and ensured the pump is on the lowest pressure, but with no effect.

Also the boiler comes on with a bit of bang too, which does not seem healthy.

The Baxi Solo 2PF is controlled by a Horstmann Centaur Plus C27 and has a Hortsmann valve.

The pump making all the noise is an Ideal CE. This pump was replaced in Sept-04 and has been working OK since then. The warranty expires in July this year.

In order to get HW I had to recently ensure the CH was programmed to come on too (with the termostat turned right down so the RAD's did not come on).

A new circuit board was put into the Baxi boiler in 2004 after an electrical meltdown.

The engineer that fitted the new pump in 2004 came 5 days ago saying that it must be some sort of electrical problem which is why the pump will not switch off and he has disappeared off the face of the planet since and is not returning any of my calls.

Hope that all helps.

Thanks

 

[Agile]

Many plumbers are uncomfortable with electrical circuits! You really need a heating engineer.

Feel the non running pump 30 min after you set it to heat the HW. See if its warm?

If its warm then open the axial screw if there is one and see if the shaft is free to turn. Full instructions in the FAQ section at top of index.

Tony

 

[geoff@cetltd]

WHatever concerning the dual pumps, ...

but pump overrun not switching off is a common fault on one version of the solo 2 pcb