Just FYI, our local fire department just did a neighborhood smoke alarm inspection for anybody interested. We asked them about CO alarms and they said that unlike smoke alarms, which are generally mounted on or near the ceiling, CO alarms are useless unless mounted near the floor. According to them, CO is heavier than air; by the time its level reaches a high-up alarm, it's way too late.

Great that you have a heavy duty hood. The oven can also be a problem. Or was for us in our last house, where the smoke detector was on the ceiling about 3-4' from the double ovens (which were mounted pretty high and we always used the top one.) It was constantly going off. Just the teensiest amount of smoke would do it, you wouldn't even really have to have smoke.

I can chime in, since we just went through this! Our town also required us to install hardwired smoke alarms when we remodeled. Our kitchen is open to a living/dining area and a pantry space. We installed ionization alarms in both the LR and pantry. They had CONSTANT nuisance alarms. They went off every other time we cooked ANYTHING (even just boiling water for pasta) or toasted anything in the toaster. It was horrendous!

I did some research and found that the ionization type cause a lot of false alarms in kitchens. We recently replaced the ones near the kitchen (LR, pantry and hall) with photoelectric alarms, and now: no more nuisance alarms! Yay! We still have ionization in the bedrooms and basement.

The catch is, if yours are hardwired together they have to be all the same manufacturer, or you risk them not operating correctly. Since the photoelectric ones with battery backup of the company we already owned did not have "mute" buttons (which I definitely wanted from our earlier experience of having to mute them every other day!), we had to change the entire house :(

There are basically two companies.... Kidde and FireX are the same company; First Alert and BRK are the same company. We originally had Kidde, but switched over to DRK/First Alert.

Thank you, Staceyneil! You answered my questions exactly!

We had to have a hardwired smoke alarm in our kitchen as well. We had false alarms from the toaster, not even burnt toast. So, we swapped it for photoelectric as Staceyneil suggests.

Our photoelectric one does not have a "mute" button, which I missed when I actually did burn some biscuits. If you have a photoelectric one with mute, can you post the model number/vendor? Thanks. (Since ours isn't hardwired to other smoke detectors, we can do any brand. I just grabbed whatever Home Depot had on hand after the umpteenth false alarm drove me nuts!)

Janet, mine are hardwired... but they are BRK 7020B.... it looks like the First Alert SA720CN might be the comparable non-hardwire model. It has a mute button!

The point stated above about CO detectors piqued my curiosity, as we have ours mounted on the wall about 6' off the floor. I did a google search and did not find ONE reliable recommendation to place it near the floor. Here is one quote I found:

Where Should I Place a Carbon Monoxide Detector?

Because carbon monoxide is slightly lighter than air and also because it may be found with warm, rising air, detectors should be placed on a wall about 5 feet above the floor. The detector may be placed on the ceiling. Do not place the detector right next to or over a fireplace or flame-producing appliance. Keep the detector out of the way of pets and children. Each floor needs a separate detector. If you are getting a single carbon monoxide detector, place it near the sleeping area and make certain the alarm is loud enough to wake you up.

I forget which site it was, but I looked at several & this seemed to be the consensus. So, CHECK IT OUT before you install one.

I'm not trying to be argumentative, but this seems pretty important to get right!

It sounds like we need to replace our alarm that is near the kitchen with a photoelectric one.
The kids call the alarm the "toast readiness indicator"...

We just installed two Carbon Monoxide detectors: one hardwired in the basement and one plug-in between the kitchen and bedrooms. The manual for the Kidde plug-in has a section titled "Installation Locations to Avoid." These include:

1)Kitchens, garages, or furnace rooms that may expose the sensor to substances that could damage or contaminate it

2) Areas where the temp is colder than 40f or hotter than 100f (crawl spaces, attics, garages etc...)

3) Areas within 5 ft of heating or cooking appliances

4) Areas near vents, flues, chimneys or any forced/unforced air ventilation openings

5) areas near ceiling fans, doors, windows or areas directly exposed to the weather

6) areas near deep-cell large batteries (large batteries have emissions that can cause the alarm to perform at less than optimum performance)

7) Do not install on a switched or dimmer controlled outlet

NO mention of height requirements, but honestly, is there any place where this plug in can be installed without voiding the warranty?? Why do I get the feeling that these instructions are all about protecting the company against liability and not about providing reasonable guidelines for the consumer....

Still searching for a suitable outlet....

After the famous umteenth alarm, I did the one thing you aren't supposed to do. I took the battery out! And it's been out for a few years. I did buy some new ones about 3 years ago. They rotate (in the package they came in) from kitchen table to other kitchen table to entryway shelf. I keep putting them on my To Do List but they don't get done. Now I think I should discard those and buy new ones. Oh, yeah, and install them!

I only skimmed answers, but I always though you were NOT supposed to have one in the kitchen for the exact reasons mentioned. One in the central hallway or just outside the kitchen is what I had thought was right, and what we have always had. So if you have a true smoke alarm, it'll sniff it out, but if you have a pan disaster, you close the door or open the windows to air it out before it gets to the detector! We've always had battery operated cheap-ish (I guess?) ones. Don't know much about hardwired.

Brendainnj - Fascinating! Are there any scientist-types reading that can tell us if CO is indeed heavier than, or lighter than, air? My hubby just told me that he saw one site that gave the specific gravity of CO as 0.997, which *would* make it lighter than air. Not sure how reliable that site is either.

I would hope that our city Fire Department would be right, but who knows? I'm only passing along what they told us. Maybe some other readers could call *their* fire departments and see if we can get a consensus? They told us that if we're going to have one, to get one that plugs into an outlet near the floor.

I'm a firefighter. Doesn't mean I have all of the answers, but here's my take. CO is ~approximately~ the same density as air and it mixes throughout the air space in a room fairly evenly. CO detectors work fine plugged in to a normal height wall outlet.

Regarding smoke detectors in the kitchen. Follow your local building code requirements, but we typically recommend that homeowners do not install a smoke detector in the kitchen. An adjoining room works fine and can help cut down on false alarms. (this is solely my personal view and does NOT represent my FD in any manner.)

I work on the insurance side of the debate and also as a volunteer firefighter.

A CO detector in the home, ANYWHERE is better then NONE.

If the city wants a detector in the kitchen,then install a heat detector, it is NOT a live safety device. A heat detector will only operate when it reaches say 135F, by then you would be out of the home because the smoke alarms in the rest of the home would have gone off. Smoke detectors, regardless what type are not a good idea in a kitchen because of as you know false alarms. The dual type (ionization/photoelectric) are the best in the rest of the home since they cover both types of fires, slow smoldering and fast moving. Install them in the hallways AND in each bedroom. I sleep with the bedroom door shut, why because I have gone to many fires and have scene that a closed door makes a huge difference from fire spread and smoke damage, you need EVERY advantage when a fire happens.

Pinch Me

Install the smoke detectors TODAY, they will save your life.

Now anyone have fire sprinklers in your home?? That is the ultimate in fire protection.

OK off the box now, back to kitchen renovations...lol

We have the Kidde PI2010 dual sensor models throughout the house including near, but not in the kitchen.

Ours is an open floor plan so there are no walls between the kitchen and the smoke alarm which is about 15' from the stove.

The ionization circuit is not as sensitive on dual models.

We never have false alarms from cooking.

Thanks all ... we ended up going with the Kidde line -- mostly PI2010s (Dual sensor) with a CO/Ionization model for the hallway outside the bedrooms and a plain photoelectric for the kitchen. The kitchen one needs to be in the kitchen, but it'll be pretty far from the range.

Once again, I'm in awe of the great information one can get on GW!

ZacsDaddy THANK YOU for starting this topic, and Staceyneil with your advice we have turned kitchen chaos into calm!

We just switched out an ionization for the photoelectric alarm and tonight broiled flank steak in total, blissful silence. The wall oven was the offender in our home, cuz our alarm is about 4 ft up and 4 ft over from it, and cooking anything at 425+ or broiling (even with the door closed) set off the shrill sound and sent cats (and company!) scampering. But no more, and I can't believe I never knew we could solve this for about $15. (fyi it's Kidde/Firex model #PE120, from Home Depot (also has the number 21006371. It's hard-wired in, but not connected to the alarms on the other floors, although it could be.)

As usual, the Kitchen Forum to the rescue!

Whoever said CO is heavier than air is misinformed. It is slightly lighter than air. If you remember your chemistry air is a mixture of oxygen and nitrogen with a molecular weight of about 29. CO has a molecular weight of 28.01 Not a large difference, but definitely not greater. Therefore it's perfectly acceptable to have a CO detector in the same place as a smoke detector.