Potterton Powermax 115 - no heating or DHW

[Observer]

Need some help diagnosing problem with this installation in a two bed flat. Condensing/combi boiler with internal stored hot water. Have had no problems up till now although have been away over summer for 6 weeks.

All indicators (lights, water pressure) on the boiler appear normal/okay but no hot water on running hot water taps and no heating on setting CH stat to full. Removed bottom and top front panels on boiler and top/front panel. Opened valves to let more water into the system and the burner light came on briefly then off again. Bled one rad which had a lot of air and recharged back to 1.5bar. Checked the air vent screw which was (correctly I think) open ~1 turn. Opened the manual bleed valve on top but no water came out. Some parts (adjacent to the air valve) are hot (too hot to touch) so there must be gas supply and some combustion taking place

Suspect there must be air lock somewhere but to fix it?

Will be grateful for any help.

 

[adlplumbing]

on this type boiler i strongly urge u to get an rgi to have look this is not boiler to play about with

 

[Observer]

on this type boiler i strongly urge u to get an rgi to have look this is not boiler to play about with

I'm trying but struggling to find someone who will come out quickly. Meantime no hot water.

Is there any simple, DIY curable fault I can check/do that I haven't done already?

 

[adlplumbing]

i have only worked on older ones and they pain as well