Need your opinion on combustion testing

RayWohlfarth

I have been trying to help a boiler owner troubleshoot some boilers from afar. When I asked to see their combustion readings, the excess air was really high. During the conversations, I discovered the tech inserted the combustion analyzer probe in the flue pipe, above the draft diverter. I suggested that to get a proper air to fuel reading, the probe should be inserted below the draft diverter. According to the owner, the manufacturer said the tech tested it at the proper place. The manufacturer said that once you set the gas pressure to the proper pressure, that is all that is needed. I would love your thoughts on this

Ironman

The manufacturer is obviously wrong. You don't take combustion readings where the flue gasses have been diluted with fresh air.

Steamhead

Ironman said:

The manufacturer is obviously wrong. You don't take combustion readings where the flue gasses have been diluted with fresh air.

This. And, there's no way you can set up a burner by just setting the gas pressure. I've seen where burners were dislodged during shipping and are producing high CO, and you'd never know unless you test.

If you're not testing with a properly-maintained and certified digital analyzer, and the know-how to use it, you shouldn't be in the business.

RayWohlfarth

@Ironman I know Couldn't believe they said that. I once saw a sooted boiler the readings above the draft diverter were tolerable.
@Steamhead Right. I always check before the dilution air
Thanks gentlemen