hole in exhaust flue

RICK_64

House has an "old" GM Delco boiler and out of the exhaust
vent(flue)about 8" where it connects to the boiler is a
1/4"or a 5/16" hole! It looks as if it was drilled for a
reset switch which is also mounted right below the above
mentioned hole. I believe this should be plugged up!?!
should a rivet be used? a screw? could there be harmful
levels of co2 emitted from a hole that size? Thanks

Unknown

Flue holes

It could be the point where analyzing equipment was inserted, can you post a pic?

Dave

Mike T., Swampeast MO

CO2 (carbon dioxide) is harmless to breathe--we inhale it with every breath. It is the product of complete oxidation of carbon.

CO (carbon monoxide) however is deadly. It's the product of incomplete oxidation of carbon. A properly functioning furnace or boiler produces extremely little--often even harmless--CO levels. If for any reason however the supply of oxygen to the boiler is reduced significantly, you start gettings LOTS of CO. Blocked flues, a boiler in a space that's too small and too tight, or even depressurization (relative to the outdoors) in the space containing the boiler can all cause the problem--thus flues are an absolute necessity.

In your lungs--just like oxygen--carbon monoxide binds to the hemoglobin in your blood. But unlike oxygen, the hemoglobin can't release the carbon monoxide. That's why even low levels of carbon monoxide are very serious--even deadly--over time. While there might not be enough CO present to cause an immediate problem, it continues to build up in the blood which in turn can carry less and less oxygen.

RICK_64

Thanks for the replies/co correction.
I don't believe the hole was for test equiptment(no-one
ever did any testing).
Which leaves the question, should the hole be plugged and if so, how? Thanks again!

Unknown

Put a screw large enough to block the hole with

a little high temperature RTV sealant(over 600 degrees). Someone probably tested it somewhere in the past that is what the hole is for. By the way it should be tested every year in order to avoid high bills and unsafe operation.

Bob Harper_2

"CO2 (carbon dioxide) is harmless to breathe--we inhale it with every breath. It is the product of complete oxidation of carbon."

Mike, I believe you meant to say we "exhale" CO2. Yes, you may inhale a teenie bit( usually less than 1000 ppm) but you exhale C02 to remove acids from the body. In fact, your respiratory drive in not to breathe in oxygen but to exhale CO2 as the body reads higher levels of carbonic acid in the cerebrospinal fluid. The carbonic acid dissassociates into CO2 in the aveoli in the lungs where it can be blown off. In medicine, we speak of "blowing off acids". --from a retired paramedic :-)

Good pickup, though.
Bob

Mike T., Swampeast MO

Thanks Bob. I got rather exhuberant in that description...

We do inhale CO2 with every breath--it's a natural part of atmosphere--small but ever-present. But I forgot how profoundly our breathing feedback mechanism is related to CO2. Thousands of times too much CO2--even when plenty of oxygen is present--and we'll essentially hyperventilate ourselves to death.