poterton performa 28 combi ch not working

[seanyp]

Hi I have a problem with a poterton performa 28 combi boiler the dhw is working fine but when i turn it to just central heating nothing happens the pump dpesnt even run yet no fault lights are flashing any ideas???

 

[baxpoti]

Check external controls are calling for heat.

Link out terminals 1 and 2 on boiler mains terminal.

 

[seanyp]

there is no external controls its controlled directly from the boiler and has no room stats etc

 

[baxpoti]

when i turn it to just central heating

elaborate.