Baxi Solo 2 Not Firing Up

[rshales007]

Hi All,

A couple of months ago my Baxi Solo 2 PF 50 started buzzing. It seemed to do this randomly, but continued to work. Putting my ear to it, it seemed to be coming from the PCB.

Yesterday, the boiler stopped working. The main fuse for the boiler had blown, so I replaced it. The fuse on the PCB had also blown, so I replaced that. At this stage, the 'boiler on' light on the PCB was coming on, but the boiler wasn't firing up. I checked all the wire for continuity and they were fine. I took the PCB right out and inspected it for damage but couldn't see any. I read on here about dry joints around the thermostat knob, so tried flexing the PCB slightly at the corner where the knob is, and wiggled the wire a bit. The boiler fired up, but didn't stay on for more than a few minutes before shutting off and going back to just the 'boiler on' light.

All this, and the fault finding diagram in the service manual made me suspect the PCB was faulty, so I have installed a new one, but, I am still only getting the 'boiler on' light coming on and the boiler refuses to fire up.

There is no power at the pump live, and the fan is not running. Is there anything else preventing the boiler from firing up, or is the new PCB duff ?

I might try the old PCB again just in case.

Cheers for your help

 

[namsag]

Changed a solo2 board the other week and on powering it up all that happened was the on light nothing else, took it out again refitted all connections still nothing... power on and off a few times and it burst into life.

 

[rshales007]

OK, put the old PCB back in. After a bit of wiggling of the thermo knob, I got a full set of lights, the fan came on, but no spark. I got power going to the control valve and the pump live. Having said that, the pump didn't actually seem to be running.

 

[rshales007]

Now put the new board back in and same as before. The on light is lit, but nothing else happens.

 

[rshales007]

Didn't get any further with this last night. Still got the new PCB installed, but nothing happening other than the 'on' light comin on. Anyone know what checks the PCB might be doing before it decides to power anything up and proceed with the firing up process. The fault finder diagram tells me to change the PCB, but I've done that.

I mentioned earlier that with the old PCB installed, I managed to get slightly further in that the fan came on, but, even though there was power to the pump, it didn't seem to be running (silent/no vibration). The PCB wouldn't be able to detect this on start-up would it ? Without the pump, the boiler would run until it overheated wouldn't it ?

 

[gas4you]

Check the aps and the pipes to it

 

[rshales007]

Boiler is now sorted. The pump had gone, but the replacement PCB which I bought was also defective. Won't get my money back on that one until Interpart have checked it. Had to buy another one in the meantime. Once I'd put that one in, boiler fired up straight away.