ferrolli sigma 40/69 system boiler co level v high

[lame plumber]

found a sigma 40/60 during a service that had v high co output, fga not happy. Cleaned everything down check gas rate, bp etc etc still .007+ so rang ferrolli engineer i know. He remembers a tech warning years ago re vertical flues on these stating that you should only use horizontal flues as they were failing to remove pocs, but a kit was available to range rate them down, ie produce less fumes! My only other thoughts were failing fan but aps allowing burner to light ok or installer didnt put in larger flue reducing ring supplied with fan/flue on installation. anyone else come across this situ?

 

[villa_tom]

found a sigma 40/60 during a service that had v high co output, fga not happy. Cleaned everything down check gas rate, bp etc etc still .007+ so rang ferrolli engineer i know. He remembers a tech warning years ago re vertical flues on these stating that you should only use horizontal flues as they were failing to remove pocs, but a kit was available to range rate them down, ie produce less fumes! My only other thoughts were failing fan but aps allowing burner to light ok or installer didnt put in larger flue reducing ring supplied with fan/flue on installation. anyone else come across this situ?

0.0070 is acceptable if your done a full strip down service. If the gas rate and burner pressure and flame picture are good and the MI's don't state otherwise on the readings then I'd say it was ok.
Id have a check of the flue ways while I was there and and if they where good and I'd done everything physically possible to try and improve the readings then I'd be pretty happy leaving it be.

 

[lame plumber]

0.0070 is acceptable if your done a full strip down service. If the gas rate and burner pressure and flame picture are good and the MI's don't state otherwise on the readings then I'd say it was ok.
Id have a check of the flue ways while I was there and and if they where good and I'd done everything physically possible to try and improve the readings then I'd be pretty happy leaving it be.

thanks for that, prehaps I should have said .007 and continuing to rise when the fga bailed out, leaving me to reset it twice. Flue clear, intake part reading 0 on CO/Co2 and 20.9 on O2 so main problem is pocs arent being cleared. So according to regs on cpa an id situ, but boiler been working for 8 years like this as last 2 services engineer didnt quote fga readings so prob dint have an fga.

Currently awaiting answer fm engineers at ferrolli, and will take it fm there.