Potterton 28 no hot water

[Cisse062410]

Hi

I have an issue with a potterton 28 boiler where the hot water system is not working(turn taps on and water stays cold). There are no warning/error lights on and the hot water light doesn't come either. I have done the electrical test as described in the manual and it points to the pcb but I have read online that the diverter valve could be at fault?

Any advice would be appreciated as I am unsure how best to test the valve to further diagnose the issue rather than changing the pcb?

 

[picasso]

Your boiler or a customers ?

 

[Cisse062410]

Its my parents boiler.

 

[picasso]

More probably the diaphragm has gone, have a google and see if the symptoms are the same.

 

[Cisse062410]

After referring back to the manual I have found that I made an error during diagnosis on the first step...... neon illuminated wasn't referring to the dhw neon...... I should stick to fixing robots and welding equipment.....

 

[gigz]

What model potterton is it ?

 

[Cisse062410]

It's a performa 28. I have replaced the differential valve diaphragm this morning and the boiler is now firing up correctly, the diverter valve is actuating and pin activating the microswitch but outlet is cold......

 

[Agile]

Is it a Performa 28i ?

 

[Cisse062410]

It just says performa 28 on the label.

 

[ianmcd]

switch the CH off and leave for the pipes to cool then run the HW ONLY and feel the CH pipes to see if they are getting hot

 

[Cisse062410]

switch the CH off and leave for the pipes to cool then run the HW ONLY and feel the CH pipes to see if they are getting hot

The central heating pipes do get hot when turning hot water tap on with boiler set to HW only........ im guessing diverter valve knackered although the pin is rising on the diverter valve.......could that mean the PHEX is blocked?

 

[ianmcd]

no that is you testing the diverter valve and if the pipes remain cold with the boiler running then the diverter valve is fine

 

[Cisse062410]

Ok thanks for the quick response. So the diverter valve is the fault as well as the differential valve diaphragm (which I've already replaced).

 

[Cisse062410]

Just an update. I have removed the diverter valve, stripped it down and refurbed it with a kit purchased of eBay as it was seized. It took just over an hour all together. Thanks for all the guidance it's much appreciated.

 

[snes]

What a real pleasure to have an OP post back with both an update and a thank-you.

Well done, that man!