Baxi Solo 3 PFL 50 will not ignite burner ???

[olrod]

Hello, I have the above boiler which is only 3-5 years old. Anyway this morning I come downstairs to the unit ticking...... And find out the Gas Supply to the Boiler has stopped. ( I am on a prepay metre ) I switch on Emergency credit to get the Gas supply back on, It has happend before. Anyway instead of the Boiler igniting and running fine it just makes a sound like its on but there is no sign of any flame??? I turn up the heating and turn on the taps but no this boiler is not heating a thing I try a reset. turn control knob to off wait three minutes and turn to settting 5. The boiler light comes on then fan light then Pilot light but not the burner light. I checked the gas, ok, I checked the wall thermastat, ok, I checked the timer, ok. So why wont this unit ignite and turn on the burner ???? Any ideas guys ? Or am I being thick?

Thanks for reading.

Mike

 

[EliteHeat]

Are you sure the gas is on?

 

[olrod]

Err yes, I get gas from my gas hob. Just no CH or HW. Because the Boiler does not want to Ignite. Maybe I am doing something wrong but its only got 4 lights and one dial !! It goes from 0-6 and has a * next to the zero. Zero is off and it usually sits on number 5 ..........

But yes GAS is on but I cannot check if its getting in unless I take the unit apart. Which seems drastic to me. I may need to call a man in ( ££££ )

 

[baxpoti]

Sounds like it's desperate for a service (a proper one)!

 

[ollski]

Have you left it ticking for 10 - 15 minutes?, If the gas pipe has emptied completely it could take a while to purge through the pilot

 

[olrod]

It not ticking at the moment. It makes what must be a fan noise and says the pilot is on, there is Gas being supplied somewhere as my gas hob works.

How often should they be serviced ? I have only lived in the house for six years and got it newly installed around 3 ish years ago.

The unit was left on ticking without gas being supplied to it for at least 2 hours it seems. As said this is not the first time, normally I credit the metre and the unit fires up or I switch it off and on again via the dial.And normally all is ok again. But this time it didn't ignite, there does not seem to be any flame at all, there is no ticking sound either now, so the unit is not sparking and does not seem to have a flame ??? there is a fan noise and there is air coming out the outdoor exit pipe. The LED say power on, fan on, pilot on, but burner off??? I now have four cold children and a runny nose If you say call out an engineer then I will do just that. Anybody know a decent place to ring in the Dartford area ???[/b]

 

[gas4you]

Every 12 months Could be the pilot injector has got blocked

 

[olrod]

Every 12 Months !!!!

The pilot injector ? Is that something I can try to solve or check ?

Is that major or minor ?

Thanks for all your help people

If you need help with a PC give me a shout :

http://www.computerandvideogames.com/forums/index.php?site=pcg

You will find me in Tech.

As you can tell Heating and boilers is not my thing.

 

[olrod]

OK .............

I have lit the (sealed) boiler with a hob igniter. The burner ignited and the burner LED came on. I left it for a while (5 mins) and the rads started to warm up. Good! But when I turned it off and on again it did not ignite which tells me there must be a problem with the igniter / spark ??? I relit it and it went ok again. This unit should not need manual lighting, it is a sealed unit after all. How can I check the igniter or fix this?

I feel I am getting warmer in solving this

 

[gas4you]

is the fan spinning? The fan needs to spin to register with the air pressure switch that it is up to speed. The air pressure switch then tells the pcb that it is ok to start ignition spark.

Therefore it could be fan, air pressure switch or pcb fault if first 2 are proved ok

 

[olrod]

I think so but I need to check further. After it went out again of its own steam I re-lit it again this time I disconnected the Spark/igniter wire the burner went out but left the pilot flame on, I then reconnected the spark wire and the burner came on ??? every time I disconnect the igniter/spark wire it goes off and when I re-connect the burner ignites !?!?!? The burner stays on until the rads heat up to the thermostat temp then off the burner goes never to come back on by itself ???? Until I re-light it.

Now I am thinking electrical ??? As I have not heard the ticking noise since it went wrong or am I barking up the wrong tree.......

I am off to bed now I will check the fan tomorrow.

 

[gas4you]

I think on this model the ignition lead is also used as the flame rectification connection, therefore when you disconnect it the pcb thinks the pilot has gone out so shuts the gas valve.

It certainley now sounds as though it is not a lack of gas problem if it lights every time with you hand igniter. Try holding the ignition lead near the metal case (don't touch the metal end of the lead ) about 3mm gap, switch on and see if you have a good visible spark

 

[meldrew's_mate]

Solos can suffer from heat hardening to the air pressure switch sense pipes, which then crack. The APS itself can sometimes fail, but usually this becomes unreliable before it fails. Stupidly these heat sensitive parts are at the top of the boiler where it gets the hottest!!!

The spark ignition is usually very quick and reliable when it gets to that stage of the ignition process, though the PCB has been known to burn holes in itself.

You should have a CORGI come out and check the boiler as replacing the APS and sense pipes involves opening the boiler casing, though you could take a flier and buy the APS, pipes, and the little plastic 90 degree bend off the top of the APS, so the heating fitter doesn't have to make two calls.

 

[olrod]

Mmmmmmmm tried that and cannot seem to get a spark from the igniter when disconnected from the burner end. So I removed the PCB very fiddly. Cannot see much of a problem apart from a slight browning of the circuit board around one or more components roughly in the middle. Failure or just heat not sure. I may just buy a new PCB and try it. Am I right in thinking if I now do not get a spark its the PCB which has failed. The fan is definitely running OK. ???

 

[Bamber gaspipe]

Sounds like pcb burnt out, you said it was left trying to ignite for about 2 hours?