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Intermittent, sub-30ppm CO readings?

Apartment has a gas furnace and water heater. My carbon monoxide monitor is a Kidde Nighthawk. Occasionally (maybe once a month) I'll noticed a reading in the 10-25ppm range stored in memory. Is this anything to be concerned about?

(My stove is electric, but I feel like I've noticed these after cooking. Not sure if stuff burning off of the heating elements would cause them though).


  • Jamie HallJamie Hall Member Posts: 13,421
    Well... not going to kill you. But worth thinking about. Trouble is, with intermittent readings like that is that it's very hard to pinpoint the source. It could be, as you suggest, stuff burning off heating elements. But it could also be... do you have a kitchen exhaust fan? Could it under certain conditions create a back draught from the furnace or water heater? And the list would go on from there...
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • amccouramccour Member Posts: 5
    I DO have an exhaust fan in my bathroom, which is pretty close to the intake vent for the furnace. I actually have tried running that when the furnace was going to see if I could get a reading, but I haven't been able to intentionally reproduce this.
  • icy78icy78 Member Posts: 382
    10-25 where the nighthawk is.
    Who knows how much at other locations.
    Serious issue there. My lo level alarm wouldve shrieked at me at 15.
    It could be from carbonization off the burners. (4000ppm has been recorded from ovens in oven-cleaning mode.)
    More likely it's as Jaime hall said , backdrafting, or maybe aircurtain effect at the water heater or furnace.
    One of our guys recorded 27ppm at a house with UL2034 wifi C0 detectors,....
    Plugged up waterheater flue due to too low flue temps. Chimney also showed 0.05" flue pressure. Too high, which allowed too much air thru the draft hood, resulting in appliance spillage into the home.
    You should have it checked I'd say. But, they need to know how.....
  • captaincocaptainco Member Posts: 460
    Is this a multi-story apartment. Are all the furnaces and waters heaters common vented from floor to floor. What about combustion air openings. I have seen apartments where the furnace or water heater on one floor spill into an apartment on the other floor. Someone that really knows the interaction of multiple systems, floor to floor, need to check this out.
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