CO detectors read "10"

[Phisherman]

I have three Nighthawk Carbon Monoxide detectors. One in the basement, one in the kitchen and one in an upstairs bedroom. The kitchen and bedroom detectors have been showing "10" for the past 48 hours (the basement reads "0"). There is an attached garage, but neither car has been running for the past 14 hours. I decided to turn off the furnace and water heater for a couple hours and open four windows. There was no change in the readings. I then unplugged them, plugged them back in, and waited an hour. The readings of "10" returned. Since there is no combustion I"m wondering where the detectors are picking up the CO? There are no noticeable odors in the house, even after being outdoors for 2 to 3 hours. Any ideas?

[Doug Miller]

Keep a window open.

Switch one of the detectors that's reading 10 with the one that's reading 0 and see what happens. If the one that's reading 0 in the basement starts reading 10 in the kitchen, call the fire department NOW.

[Edwin Pawlowski]

CO has no odor but with no combustion (that may have an odor) it is hard to say what the problem is. You fire department will have detectors that can check things out for you. Better to feel a little silly if nothing is wrong than to be DEAD right. They won't mind coming out on a service call now rather than a rescue call at 3 AM.

[Joseph Meehan]

Call your local fire department. They will be happy to come out and check. They like people who buy and use safety equipment. They really don't like finding dead bodies. They can check it out for you and offer suggestions if needed.

[Art]

I would call the fire dept unless the one that reads zero continues to do so when moved to the spot that the other one reads 10. They do have a limited lifetime though in any case. So do you.

[Steve B]

Have you read the directions?

On mine, it says that furnaces, fireplaces, and even street traffic can be detected by these detectors.

A reading of 10 is very low.

Just for the sake of discussion, what is the threshold level? The level at which you should be concerned? What did it say in the directions?

Steve

[AZ Nomad]

keep in mind that CO is odorless.

If you like your braincells alive and healthy, don't spend another night there until you solve the situation.

[Jim Shortz]

Move the basement detector to the kitchen and see if it reads 10 or go buy a new one, try it and return it if the old ones are not found to be defective.

[Art Todesco]

[buffalobill]

"Replace CO Alarms Every 5 Years Carbon monoxide alarms are valuable lifesaving devices that, when used and maintained properly, are effective at detecting carbon monoxide in the home before it reaches lethal levels. Kidde recommends that you replace your carbon monoxide alarm every 5 years from the date of manufacture in order to upgrade to more advanced carbon monoxide sensing technologies and new innovative safety features. All UL-listed carbon monoxide alarms are required to publish the date of manufacture on the label accompanying the product (usually on the back of the alarm). Kidde also recommends testing carbon monoxide alarms monthly to ensure they are in proper working order and that batteries are still fresh. It is also important to have home appliances checked annually by a qualified technician. Carbon monoxide alarms are designed to activate in accordance with UL Standard 2034. Individuals with medical problems or those believing they may be susceptible to lower carbon monoxide levels may consider purchasing a warning device which alarms at lower levels of carbon monoxide than those specified by UL Standard 2034. " so it says at:

[trader4]

I guess we found the cheap skate that buys things, uses them, then returns them, so the rest of us can pay higher prices.

[trader4]

That's a very interesting way of putting it. I had always heard that these detectors have a limited life because of the sensors in them, not because the manufacturer wanted to sell something new. If it's true that the existing ones have a limited service life for a valid reason, you think the manufacturer would have sense enough to just say that, instead of this BS. I could make that same statement about my furnace or dishwasher, yet we all know they last a long time.

All UL-listed

[Jim Shortz]

I doubt a half hour of use a on a retuurned CO detector would strap your finances too badly.

[jaykchan]

Read the instruction of the detector to see what "10" means, and what the instruction recommends you to do. If the instruction says that it is a dangerous level, trust it and call Fire Department and stay out of your house.

My family (including me) almost died of carbon monoxide because I didn't trust the detector and spend too much time playing detective (trying to find out the source of the CO, and trying to see if the detector was defective or not). I was much better off trusting the detector and let the Fire Department to figure out what went wrong. Turned out a squirrel got stuck in the chimney and blocked the vent of the water heater. My family and I are all fine; but the squirrel of course was dead, and my ego was not intact either.

Jay Chan

[zxcvbob]

I have a Nighthawk, and it drifts up to about 7 or 8 occasionally (sometimes 9) for no apparent reason. Even with the windows open. Resetting it doesn't help. Eventually, it settles back down to zero. The detector works great when there actually is a CO problem (trying to light a cold wood stove, or one big smoldering ember in the stove which then start backdrafting.) I think it just loses it's zero calibration.

10 is a high enough reading to almost start being a little concerned. Almost. HTH :-)

Best regards, Bob

[Steve B]

wrote

Like you never did it.

A person who tells you he's honest will probably lie to you about other things, too.

Mark Twain or Will Rogers

Steve

[George E. Cawthon]

Read your manual. It doesn't mean anything and the detector can't detect a reading that low, so

10 is the same as 0. Mine read 10 for a while, went bonkers when the power went off, I replaced the battery (it ran down rather fast with the power off). Reads 0 all the time now. When you unplugged the thing did you take the battery out? If not, you need to and also replace the battery.

[tekIQ]

[George E. Cawthon]

Nonsense. A reading of 10 has no meaning and many CO units can't detect anything under 25. Let the guy read is manual. No alarm is even sent unless the reading gets above 50 for a long period. A peak reading doesn't even begin until above 10. A reading of 10 has no meaning, except that the unit may have malfunctioned.

[George E. Cawthon]

Better to read the manual, then one wouldn't have to feel silly.

People in a rational household don't die of CO poisoning. Those that die are in cars, campers, motorhomes, and tents doing stupid things without ventilation, or simply trying to kill themselves, and people in homes that have done something extremely stupid like bringing a hibachi into the living room to stay warm or cook something.

Chronic CO poisoning is a bit different but your CO detector may be useless for detecting that.