Greenstar Ri Boiler -

[tel.54]

3 year old installation with a Greenstar 24 Ri and Sunvic S plan controls.
Occasionally the pump does n't switch off when there is no demand.
During this period the boiler fires but radiators do not warm up.
The pump has a mind of its's own and will perhaps switch off after a few hours

The system seems to work normally when in a timed period.

 

[quality]

So (please excuse my french) what is the problem
Have you had it serviced since the install 3 years ago ?

 

[tamz]

The pump should be wired back to and controlled directly by the boiler.
Have you got an auto bypass fitted?

 

[tel.54]

Yes Tamz - to both questions.I know the the overrun should be approx 3 mins but it can go on for hours or not stop atb all

 

[tel.54]

Hi Quality
The problem is the pump is running and the boiler firing when there is no heat demand.

Yes it's been serviced every year and the Service engineer called yesterday , but like all intermittents
it could not be duplicated when the expert was around.

 

[tamz]

I would start by checking the wiring to the boiler block ST2 especially if the pump goes to the boiler through a wiring centre. Pump live is to the left and switch live to the right of the block.
If that is ok check for back feeds from the motorised valves (sticking microswitch).

 

[tel.54]

Thanks Tamz - I'll try that

 

[mmi4790]

I have a similar problem. I switch on the hot water only and the radiators start warming up. On another occasion, when I switch on the radiators they stay on even after 1 hour when the timer has switched off.

 

[tipintim]

I have a similar problem. I switch on the hot water only and the radiators start warming up. On another occasion, when I switch on the radiators they stay on even after 1 hour when the timer has switched off.

Is the system your refering too
1. a new system
2. An existing system upgraded

 

[PlumbBobBob]

symptoms point towards three port valve passing

 

[tipintim]

3 year old installation with a Greenstar 24 Ri and Sunvic S plan controls.
Occasionally the pump does n't switch off when there is no demand.
During this period the boiler fires but radiators do not warm up.
The pump has a mind of its's own and will perhaps switch off after a few hours

The system seems to work normally when in a timed period.

If it works in timed period, happy days. Time it for your consumtion. Sounds to me it has not been commisioned and switched to user mode.

 

[mmi4790]

It is an exiting system upgraded. I think the problem is to do with the port valve as suggested by steveb. There a black switch which can be moved. I have moved and now the radiators don't come on when I just switch on the hot water.

 

[mmi4790]

Thanks for the info. I think this could be the problem. There a black switch which can be moved. I moved it and now the radiators don't come on when I just switch on the hot water.