Biasi Riva Compact combi boiler

[Jacko]

Hello All
The pump proving switch on the above named boiler does not retract.
As soon as the boiler is pressurised the pin comes out even with no power to the boiler.
The pin is not warped, the diaphragm has been replaced and there is no debri behind the diaphragm.
What causes the pump proving switch to be fully out with no demand on?

 

[Riley]

Are you gas safe

 

[Jacko]

Yes. 539230

 

[Riley]

@ShaunCorbs sorry bud have to ask we have a strict non diy gas policy. Shaun should be able to sort you

 

[Jacko]

yeah no worries mate, totally understand

 

[Riley]

We take discussion like this off open forum to avoid prying eyes. Stick around there’s some really knowledgeable guys

 

[ShaunCorbs]

hes gas safe reg help away will sort it out

 

[AMGasServices]

Have you tested the micro switch withyou multi meter ?

 

[Jacko]

Have you tested the micro switch withyou multi meter ?

The flow switch works fine. Once reset I can create a demand and manually engage the switch and the boiler fires up, when I then release the switch the burners go off. The pin on the manifold stays out on goes down when the boiler is depressurised.

 

[AMGasServices]

Is it a single board or twin board ?

 

[Jacko]

Is it a single board or twin board ?

Single green board

 

[AMGasServices]

Do you have any lights flashing? Could be a weak pump or PCB

 

[Jacko]

Do you have any lights flashing? Could be a weak pump or PCB

When the pump stops after a demand the lights flash indicating a primary circuit or no flow fault. I assume if it was a weak pump the pin wouldn’t come out fully, this pin comes out fully and that happens even with the power isolated???

 

[AMGasServices]

I’ve had it on an mini where the pin comes out fully it doesn’t have the force to make the micro switch.

If not ring technical department on Monday.

 

[bill577]

I would check for a blockage on one of the connecting pipes, try using a magnet around the pipes to the flow switch.

 

[Jacko]

I would check for a blockage on one of the connecting pipes, try using a magnet around the pipes to the flow switch.

Hello all thanks for your help,I changed the complete flow manifold and it’s all working now. The fault was limescale build up in the manifold stopping the pin retracting. There are no connecting pipes to this boiler, once the pressure of the boiler stops the pin should retract.