Boiler not firing up after refill.. help please.

[dougie212]

Hi there..

So, after flushing my boiler system to release what appears to have been an airlock in some pipework (had a very satisfying splutter and huge surge of black muck out of the drain valve) for my new radiator...(previous thread), I have today gone and bought some Central heating cleaner. Added it via a radiator, filled the system up, bled the radiators and the pump via the big centre screw as previously advised, all up to pressure...turned the boiler on and it switches on, but doesn't ignite....... the pilot light is lit, all the usual lights are on but its not igniting. Tried the hot water, and again, its firing up but not igniting. I only know of the centre screw on the pump to drain air out, is there anywhere else? Many thanks in advance. Ive *hopefully* attached a pic of the dam boiler.........

 

[GQuigley67]

Shut down all radiators bar one, try force the airlock to that radiator and bleed it. Gravity systems are a pain with air locks, I usually just stick automatic air vents in when draining down to save me the hassle

 

[dougie212]

Thankyou..! Do you think its an airlock then thats stopping it from igniting? The boiler is in the bathroom so I think I might shut everything off but that one.. I assume I shut them all off and turn the boiler on. will it move it even though its not igniting?

 

[joni os]

You will soon be told, correctly, you need to be gas safe to work on boiler and the thread will be closed. What you can do is check and clean the gauze filter, located where return flow attaches to boiler. It is possible that moving sludge around system has caused blockage at this point.

 

[dougie212]

I'll close it now then, thought it was ok as long as I dint touch the gas side... which trust me... Id go no were near. I was just curious if there was another way of venting the boiler.. but I'll close it .

 

[gassafe]

That thing looks old!

 

[GQuigley67]

You will soon be told, correctly, you need to be gas safe to work on boiler and the thread will be closed. What you can do is check and clean the gauze filter, located where return flow attaches to boiler. It is possible that moving sludge around system has caused blockage at this point.

He's not tampered with the boiler just the system, you don't need to be gas safe to open the pump vent.

To op, best gettin someone in, if it was an airlock or blockage it would fire up then overheat, if it's not firing at all then time to get a gas engineer in.

Parts might be obsolete though as it looks really old

 

[hammers4spanner]

Parts are obsolete

 

[gassafe]

Some systems are so old they don't like being tampered with, leave them alone & they will tick along happily, drain them down, add sludge remover & everything else & a lot of crap can get disturbed & lodged into places it shouldn't be...

 

[dougie212]

Think its time to look to get it replaced.... Does anyone have any recommendations in the Cannock/Stafford area? Spoke to my parents and they have suggested British Gas, but am guessing they will be 10 times more expensive than most.. Its a combo boiler and I'd just like a straight change.. thanks

 

[Atouchofgas]

That's an old Vaillant vcw242 by the looks of things you can access those parts without disturbing anything Gas related ( although there should be a grey panel in front of the pump and controls ).
If everything's running but not firing then I think you're going to have to call a gas engineer out.

 

[dougie212]

Just gone to try it again, and nothing is running now. I turn the hot tap on and get a click, and nothing...... Time for a new one I think

 

[joni os]

Your experience has confirmed quantities of sludge in existing system, you are also competent to remove and reinstall radiators. Most important new boiler goes on clean system. Rather than rely on others to power flush, drain down, remove rads and individually hose through. Purchase four 1/2" hose tails in the following sizes:- 1/2" BSP male, 1/2" BSP female, 3/4" BSP male, 3/4" BSP female. You can then use the male fittings to connect and assist flush of rads, invert and tap with rubber hammer while flushing. The female fittings will allow you to fit drain hose to radiator valves and flush pipework with mains pressure water via your fill loop, one valve at a time.

 

[dougie212]

Problem solved.... I took the chrome cap off the pump and manually span it to free it off... that got the pump running again, then at the back on top of the boiler is the AAV. That was rather crudded up, gave it a little squeeze and some air came out.... turned the system on and could still hear the water bubbling with the air so (rightly or wrongly) I give the AAV a gentle tease with some pliers while the boiler was on, and out came a whole heap of air, and whoosh the thing fired up... chuffed...! just a little issue with the TRV now.... (I'll start a new thread...) Thanks everyone so far...!