Help it's cold!

[angel150]

Does anyone have any ideas why my boiler turns itself off when it snows?

We have a Potterton Profile 40e most of the time it's brilliant, but when it snows (not very often in Brighton) it doesn't like it and it turns off. Had it serviced 2 years ago and it didn't do it last winter, but today it did it again.

The reset button (Can't tell whether you've done anything or not) didn't seem to work. The thermostat since it happened seems to think its 20 degrees c - it's definitely not!!

I have finally managed to get it to ignite by turning it off and then on again at the mains. Any idea what is going on? Is it overheating when it gets this cold in which case why won't the reset work even though it's stone cold?

Is it the thermostat which isn't getting it to reignite when you turn it up? and is it safe to keep relighting it by turning the electric on and off?

 

[bab]

Is snow getting into the flue as this will stop it working. seen it before

 

[angel150]

Flue sticks out at right angles on kitchen wall about 3m from a 8m high wall. It's possible some sleety snow could blow into it but not much and I think it turned itself off after it stopped snowing today. If it is that is there anything I can do? Also just remembered I dusted the top of the thermostat this afternoon, could that have any effect?