Potterton boiler not starting

[Cake]

Good afternoon,

before starting i would to say i have been looking around this forum for many hours and no one has exactly the same issue or its not fully detailed for me to go 'yes thats it'.

I have a Potterton 50l boiler and its just broken down.

The boiler starts and ends after 1 minute with the green light solid, red light flashing and fan spinning. At no point does it spark, nor can i smell gas.

From reading other posts it can possibly be the air pressure switch or the PCB.

I have checked and gas is running to my cooker and being a sealed system off mains, all taps have full pressure.

One additional factor is that i currently have a radiator removed and valves closed, these were changed the other day too. I have not started the central heating during any of this and only hot water on. Expansion tank pressure is currently 0. My ehating working is not needed right now as when the radiator is back on i will get a plumber to come and top it up/pressurise it.

I am not looking for a home fix but advice on what its most likely to be any any simple tests i can do so when an engineer does come i have all the information i need.

 

[hanns21]

First thing is if its a presurised system it wont work unless the pressure is topped up. Secondly a gas engineer knows how to do his job and doesnt want you guessing to him how to do his job! You wont get much help on here from anyone when its to do with combustion.

 

[45yearsagasman]

Your post looks like a 50l, but I assume its a Suprima 50L? As said, it will most likely be a fault that is only repairable by accessing the combustion chamber, and as such,you require a competent person.

 

[bazdaman]

If no pressure in it could be flow related some suprimas had a flow switch that was wired through the APS, put some water in and give it a whirl