Soot above gas fire

[ajsdoc]

We have a Valor 541 Ultimate gas fire.
We had it serviced only a month ago. We have it serviced yearly with the boiler.
Recent power cut for 2 days (don't ask)so ended up using it lots (otherwise hardly ever used)
We've noticed a small amount of soot on the marble of the shelf above.
Flue is clear outside. CO detector in room working but not gone off.
Is a small amount of soot normal, or should I be getting our gas man back?
The coals look correct according to User Manual.
I appreciate hard to advise, just don't want to overreact.
Thanks in advance.

 

[twgas]

Soot is a BIG NO-NO, turn it off and get it checked out

 

[Tibbot]

Soot on a gas fire surround is a sign of POC spillage and is dangerous so it mustn't be used until made safe.

 

[ajsdoc]

Yep, thanks. Thought you'd say that. Will get him back again.

 

[gas112]

marble back panel will not be sealed to the wall properly if your only getting staining on top

 

[richardrich79]

Soot on a gas fire surround is a sign of POC spillage

Read more: //www.diynot.com/forums/plumbing/soot-above-gas-fire.385717/#ixzz2mar3vZ4b[/QUOTE]
Sorry to ask but what's POC

 

[Madrab]

Products Of Combustion