Funny noises from boiler

[maurelius1]

Hello all,

I have a strange problem with my boiler. It is a Worcester 24CDI combi boiler. Last night while my wife was in the shower she suddenly remarked that the water had gone cold.

I looked at the boiler itself and it was making some funny hissing noises like someone was spraying an aerosol. I managed to trace it to a valve looking thing on the top front left of the boiler itself.

The hot water and ignition lights were still on.

I could have sworn there was a smell of burning as well (but cannot be sure) so it got turned off pretty quickly

Does anyone have any ideas what this might be? Any help is appreciated.

Thanks

 

[petit_pablo]

Either a blockage or pump is a likely candidate. Does it do the same on heating?

 

[gremlin16]

Faulty pump.

 

[maurelius1]

Either a blockage or pump is a likely candidate.

Oh dear!!

Does it do the same on heating?

I darent turn it on....don't know what it'll do!!

 

[nogoodatfaultfinding]

What is the water pressure like????
Are you sure the hissing was not the boiler over pressureising and blowing off??
As that tends to sound like a hiss from the inside.

 

[maurelius1]

What is the water pressure like????
Are you sure the hissing was not the boiler over pressureising and blowing off??
As that tends to sound like a hiss from the inside.

Water pressure seemed normal at the time (in the shower; just that it went cold) the hissing could well have been inside it was quite difficult to track down at first.

Presumably the over pressurising and blowing off would be caused by a blockage maybe???

Should the black valve on top of the unit be tight or loose?

If I switch it on to see whether the central heating is effected could I damage it?

I assume an engineer needs to make a visit?

 

[nogoodatfaultfinding]

Sorry did not explain myself very well.
I meant the preesure gauge on the boiler, its a dial that usually states between 0 and 4/5.
And no if it is blowing off it is not nessecery(anyone else struggle with that word?) a blockage.
I dont beleive although hard to tell over a moniter that you would be in any danger however if for peice of mind leave it off, check the gauge then come back.

 

[maurelius1]

Sorry did not explain myself very well.
I meant the preesure gauge on the boiler, its a dial that usually states between 0 and 4/5.
And no if it is blowing off it is not nessecery(anyone else struggle with that word?) a blockage.
I dont beleive although hard to tell over a moniter that you would be in any danger however if for peice of mind leave it off, check the gauge then come back.

The pressure was about 1.6bar when the noises started and as it cooled down it settled at 1.1bar when we switched it off.

 

[tonybhoy]

Sounds like the AAV was blowing out air/pressure.

AAV=Auto Air Vent. Boiler might have been overheating=faulty pump,as the other guys said above.

 

[maurelius1]

Sounds like the AAV was blowing out air/pressure.

AAV=Auto Air Vent. Boiler might have been overheating=faulty pump,as the other guys said above.

Doh..thanks for all your help guys, it is appreciated.

I'll arrange for an engineer to have a look.

Ah well.......