we have a wrocester 24i combi, i think its about 8 years old. we have it service every year by BG and had them out several times for odds and soods.
This problem started around 5 years ago but the problem only happened maybe 2 or 3 times a year, now though its happening around 2 or 3 times per week.
Ok, as you see in the picture a combi boiler.
Bottom right, the pressure clock, next to that the timer swtich with the on /off and timer button. next to that on the left is the heat control switch, you turn in for the hotness of the water.
Ok, the problem.
There is a switch on the timer, on, off and time setting (like a clock you can set it to go on and off at a certain time) We use the switch to turn the appliance on and off, we never use the timer as we only have heating either on all day or off.
ok, to swtich the combi on the switch is set to the bottom, on doing this the appliance fan goes on, this is a noice hard to describe but the fan comes on, after a few seconds the appliance ignites, you can hear this noise like a 'whoosh' gas igniting kind of noise. Then obviously the radiators get hot and we have hot water.
We have noticed that several times a week, that some times we feel a little cold and feel the radiators and they are cold, the appliance has gone off, so i go upstairs to the boiler and the fan is still going but obviously not working the, lets call it the ignitor as i do not know technical names. So now i can run the hot tap and only cold water comes out, the hot is now not working. The only way to get things back to normal is by turning the boiler off, waiting 5 minutes until the fan dies then return it back to on, and again the fan starts, then a few seconds later the appliance ignites and again we have hot water and the cenral heating is working.
This is an intermittent problem, it happens about 2 or 3 times a week, some days its ok, heating on all day and no probes, but another day the heating can be on from 9am in a morning then sometime on the evening the rooms get cold and we find the heating if off.