Potterton Kingfisher CF50, No hot water

[DougInsole]

Can anyone help, Potterton Kingfisher Gravity Fed Boiler, No Hot Water,
Central Heating works. Replaced 2 way valves, both tanks in loft full of water. Electric immersion heater works when switched on and full flow of hot water, can not understand why boiler will not heat water when switched on?

Thanks

 

[twgas]

It sounds like a boiler fault and as there are very few parts on these boilers my best advice is to call a RGI. Also as its open flued it will need the flue checking.

 

[rojaca]

Just to be sure, you have two seperate zone valves- So DHW circuit is pumped not gravity?
Are you getting any voltage to the boiler from the dhw zone valve when programmer and cylinder stat calling.
Does your boiler make any attempts to fire on DHW only?

 

[Agile]

You say you have replaced both two port valves! One might ask why both.

If they are correctly fitted and the HW valve is not opening then its obviously a fault between the programmer and the valve. This will include the cylinder stat.

Tony

 

[DougInsole]

Just to be sure, you have two seperate zone valves- So DHW circuit is pumped not gravity?
Are you getting any voltage to the boiler from the dhw zone valve when programmer and cylinder stat calling.
Does your boiler make any attempts to fire on DHW only?

Thanks for the reply, The programmer lights come on when I select HW and CH, it appears that only the valve for the CH is responding, the HW valve Manual /auto selection is stiff, ie same when the programmer is off.

The boiler fires up when I select the CH option, but does not fire up when I select just HW only.

 

[DougInsole]

You say you have replaced both two port valves! One might ask why both.

If they are correctly fitted and the HW valve is not opening then its obviously a fault between the programmer and the valve. This will include the cylinder stat.

Tony

Hi Tony

They were Honeywell valves and looking very tired, so thought it best to replace them both at the same time. Do you think it could be the thermostat on the side of the cylinder that is playing up, anyway I can test this before replacing.

Regards