banging in the boiler and airing cupboard

[littlepie]

Can any one please help me, Have no heating or hot water at the moment. When I switch on the heating system, the boiler fires up and the pilot light comes on but after about 30 seconds the light goes out the boler starts to bang and the pump (which is in the airing cupboard upstairs) starts to bang and it sounds like it might explode. I had the pump replaced in January, and I had the boiler serviced in February. I bled all the raiators last night - there was only one that sounded like it had some air in - so now don't know what to think. The boiler is a Potterton Suprima. Have called a plumber but he can't come for a few days so any help would be much appreciated

 

[Lagerkhan]

Can any one please help me, Have no heating or hot water at the moment. When I switch on the heating system, the boiler fires up and the pilot light comes on but after about 30 seconds the light goes out the boler starts to bang and the pump (which is in the airing cupboard upstairs) starts to bang and it sounds like it might explode. I had the pump replaced in January, and I had the boiler serviced in February. I bled all the raiators last night - there was only one that sounded like it had some air in - so now don't know what to think. The boiler is a Potterton Suprima. Have called a plumber but he can't come for a few days so any help would be much appreciated

Did you get water out when you bled ?
Check that you have water in the small expansion tank and that you have water in the system.

 

[Timmyturtle]

If its banging its probably a flow problem,ie sludge in the system.
I believe the some(if not all) Suprimas had a flow switch which will turn the boiler off if low flow detected,though i may be wrong.
If theres no flow the boiler stat will also cut it out because it cant get rid of the heat quick enough.
If there is no or low flow the boiler will basically heat the water untill(and beyond if allowed) It boils.If the water boils it creates "air" which in turn causes a banging noise.(like a kettle thats almost boiled gets noisy)
Thats the 0 from H20
Does the pump actually turn?
as its been done recently has a wire come out from the pump...check for live feed

 

[littlepie]

yes a small amount of water came out, how do i find out if there is enough water in the system? soory if i sound thick!

 

[Timmyturtle]

The small tank in the loft needs to have water in it....or
If pressurised needs to show approx 1 bar on gauge

 

[gas4you]

Check the pump again. It may be faulty! Next you need to check that the live for the pump is live, this comes from the suprima pcb. If this is dead then could point to a pcb fault in which case you will need a new pcb

 

[meldrew's_mate]

If the water boils it creates "air" which in turn causes a banging noise.(like a kettle thats almost boiled gets noisy)
Thats the 0 from H20

Not quite right, but the rest is good advice.
When water boils it produces steam, not air. This expands to about 22,000 times it original volume, then promply condenses back into water, and contracts, when it hits the cooler water above. The subsequent shock wave causes the rather violent banging, and it is this which can cause boiler and pipe damage if left unresolved.

Check the pump.