Gas Boiler sometimes ignites with a whump

[RogerBlake]

My Ideal ICOS Gas condensing boiler occasionally starts up with a Whump! instead of it's normally quite silent start up. It seem to do this at random. Any ideas?

 

[bster]

Igniter\pilot pipe may need cleaning as its not igniting the gas straight away resulting in a small build up of gas before ignition?

 

[kevplumb]

or failing that GET IT SERVICED

 

[Agile]

Igniter\pilot pipe may need cleaning as its not igniting the gas straight away resulting in a small build up of gas before ignition?

Sorry apprentice but the Icos is an advanced premix boiler! Pity about the PCB and the AAV which leaks on the display module!

The spark ignition electrodes obviously need to be clean and correctly gap set to 4 mm as all good servicing engineers would check!

If that problem is intermittent it is often due to a sticking gas regulator on the meter.

Try seeing if its any different with gas cooker on or off.

Tony

PS Good word that "whump", will have to try to remember it !

See:- http://encarta.msn.com/dictionary_/whump.html

 

[nickso]

crakced or damaged burner can cause the same thing but ive found the icos/isar burner to be quite good at resisting normal wear and tear.

might be worth a look in case someone has damaged it and just stuvk it back in.

 

[ChrisR]

correctly gap set to 4 mm as all good ....

Er
3mm +2 -0 for the M series,
3.5mm +/-1 for the later HE ones

I think those are right, but check the manual.

Also check flame detection electrodes (including earthy one at the back) / ionisation probes, depending on model.

 

[corgiman]

bet you their crappy little condense trap is blocked

that causes a mighty whump