Baxi 80 Eco Wont Ignite

[dry_flood]

Hi everyone. I have a Baxi 80 Eco Combi boiler that wont fire up. When I reset the boiler and turn on the CH & HW it tries to light and you can here it sparking but after 10 seconds or so it stops and the ignition failure light comes on. This happens every time & it refuses to light.

I have a friend who has been corgi for 7 years but works for a builder and only fits systems in new builds. He doesnt do any kind of repair / diagnostic work. He had a look and said that it was more than likely the flame sensing electrode and lead. So he got the replacement parts, fitted them and after a few tries the boiler ignited and the CH came on and worked as normal

About 4 hours later I was running a bath and the water kept going from hot to cold. I turned the boiler off just in case. I left it a while and tried to light it again but now I am back to square one as it is refusing to light.

Something tells me that the new parts didnt make any difference and it was probably because he had the front off the boiler and the PCB exposed. Maybe a loose wire?. I turned the boiler off at the mains and made sure that all of the wires were connected to the PCB correctly but that didnt make any difference.

I would appreciate it if someone could suggest some possible solutions or anything that i can tell him to check.

Gaz

 

[Agile]

The first thing for a CORGI to do with that kind of fault is to measure the gas valve min/max pressures. Very common on your model.

There are several things which could cause that problem, like faulty gas valve or faulty PCB.

Rather than throw parts at it I would always recommend having the fault diagnosed properly.

Tony

 

[dry_flood]

I have suggested what you said to my CORGI friend and maybe he is out of practice but he says that it would be hard to measure the gas valve pressures if the boiler is not lighting as it wouldn't keep flooding the chamber with gas if it cant light it.

He is adamant that the PCB is fine as it is not showing any of the symptoms that the manual says for a dead pcb.

He is coming round at 6 and is going to try it. Are there any other things I should get him to check?

Gaz

 

[Baxmax]

I really feel these are basic diagnostics,is there a sprark ? yes , is there gas present when the spark is generated,mmmm.....what method could i adopt to acerertain gas is present or not at the same time the spark is generated....I am sure i should know this.... And so on and so forth

 

[dry_flood]

Ok. He checked the gas pressures this evening. The mains gas is showing the correct pressure into the boiler but it is not registering a pressure on the gas valve when the boiler tries to light. After going through the fault finding in the manual we have agreed that it is more than likely the Gas Valve.
Looks like you were right on this Agile.

I have sourced a new one (boxed & sealed) for £55 for my boiler from a seller on ebay. It turns out that the original gas valve is no longer made and it has been replaced. This was very cheap compared to the other prices I found and even cheaper than he could get it from any of his suppliers.

Will be fitting it on Saturday so will give you all an update then.

Gaz