Baxi Solo 3 switching off when room stat still should be calling for heat

[Ryan Huskinson]

Hi, I have a problem with a Baxi Solo 3 system...I've had 2 engineers come out to it now and still not working correctly for some reason.
I have had the 3-port motorised valve replaced, room thermostat and programmer and boiler serviced.
It works fine for 30 mins to an hour and all radiators nice and hot and so is the hot water. After this period the boiler stops then has the 'Boiler On' light and 'Pilot' light both on. Boiler then fires up after 10 mins or so can sometimes be quite a bit longer, but then no heat through the radiators no matter how long I leave it doing this on-off cycle. Still have plenty of hot water though. If I switch it off completely at the programmer and switch it on after a few hours it follows the same pattern of all rads fully hot, system off, rads not hot etc etc.

The pump seems to be running and can hear and feel the difference when I change the speed setting (I typically leave this on 2) and the boiler dial on about 3.5, the 3-port valve finds the correct position when changing the programmer settings and the room stat is set to between 18-20°C but heating can't have met that demand as it is no more than 10°C...can almost see your breath its cold...the overheat light has not come on once...is this fixable does anyone know? Thanks

Read more: //www.diynot.com/diy/threads/baxi-solo-pfl-30-starts-stops-starts-stops.471365/#ixzz4S4gon2yz

 

[ianmcd]

Ask your engineer to test the potentiometer it is detailed in the installation and servicing instructions how to test it and also test the thermostat sensor when the boiler starts playing up if these are both OK I fear you could be looking at a replacement pcb so might be worthwhile looking at a Baxi fixed price repair as you seem to have wasted some money already, something else that you might consider is I see SSE advertising that they will repair your boiler free of charge as long as you take out a boiler care plan about £20 a month I think, but be warned they have some really poor engineers and might take forever to get to the bottom of it, Baxi fixed price repair would be your best bet I think

 

[Ryan Huskinson]

Thanks for that Ian hope this does the trick

 

[AGAS]

i thinks thats the best advise you can get as ianmcd has advised , get baxi fixed price repair to sort the problem , believe it or not it would probably be cheaper in the long run . thats if you don't know anyone really reliable with fixing boilers .

 

[stem]

get baxi fixed price repair to sort the problem , believe it or not it would probably be cheaper in the long run

Yes indeed. I had a Solo 3 with a very similar fault about 10 years ago, and paid for a fixed price repair £200 ish I think at the time. It was an intermittent fault and the guy who serviced my boiler wasn't sure what the problem was, so made the same suggestion as AGAS. Baxi came out, and over several visits fitted:

New PCB
New gas valve
New fan
New air pressure switch

All in all, I reckoned not far off £1,000 of spares and yet the fault persisted:

Finally they swapped the thermostat sensor. Problem solved, and this is probably the cheapest spare part for the Solo 3 at about £10

So, I kept the old parts as spares. The guy who services the boiler, is quite happy to fit them at £30 a time, when I have a failure, so far, the fan, circuit board and, air pressure switch have been used, so all in all it was good value.

 

[Ryan Huskinson]

Thanks Stem I shall have that checked first just in case

 

[jeff the gasman]

Solenoid