carbon monoxide, tap over speaker?

baja_van · 12-20-2021, 08:11 PM

since winter is here and i picked up a "Mr. heater", i want to install a carbon monoxide detector.
i picked on up at my loco hardware store. but thinking it would be to loud in a van. it would only be 5" from my head when sleeping.

could i put some tape over the grille for the speaker or is this also how it detects? when i open it up, i can tell that a speaker is under the grille but started thinking how does it detect?

thanks

1der · 12-21-2021, 12:43 AM

A CO sensor should be mounted lower than your head level when sleeping and in the area where the heater is going go be operating. CO is heavier than air. It will be loud anywhere in the van, which is what you want.

A Mr. Heater unit is a catalytic heater. It is not supposed to emit CO but it will use up the O2 in the space it is operating. This is the concern and the CO sensor will not help w detecting the O2 depletion.. Make sure you leave enough open window / vent to allow some fresh air to replenish what the Mr. Heater is depleting. This introduces more cold air into the cabin which then has to be warmed.

You will also have to deal with the significant moisture that will be introduced into the cabin by conversion of propane to heat. The amount of moisture you exhale plus the heater generated moisture will condense on the cold windows and cold metal inside your cabin.

**daveb** · 12-21-2021, 02:26 AM

Ray is spot on. If the heater doesn't work out for you, a 12v electric blanket or pad might be an inexpensive solution or a good backup.

baja_van · 12-21-2021, 05:49 AM

Quote:

Originally Posted by 1der

A CO sensor should be mounted lower than your head level when sleeping and in the area where the heater is going go be operating. CO is heavier than air. It will be loud anywhere in the van, which is what you want.

A Mr. Heater unit is a catalytic heater. It is not supposed to emit CO but it will use up the O2 in the space it is operating. This is the concern and the CO sensor will not help w detecting the O2 depletion.. Make sure you leave enough open window / vent to allow some fresh air to replenish what the Mr. Heater is depleting. This introduces more cold air into the cabin which then has to be warmed.

You will also have to deal with the significant moisture that will be introduced into the cabin by conversion of propane to heat. The amount of moisture you exhale plus the heater generated moisture will condense on the cold windows and cold metal inside your cabin.

ok. thank you. so it would be better to get a lp/o2 sensor then?
i thought carbon monoxide is slightly lighter then air?

**BroncoHauler** · 12-21-2021, 06:43 AM

Yes a CO alarm is loud, so don't place it near your pillow, but it's job is to get you up and out of the confined space. Loud is good when your life depends on it.

Herb

1der · 12-21-2021, 07:54 AM

Quote:

Originally Posted by baja_van

ok. thank you. ........
i thought carbon monoxide is slightly lighter then air?

Dang, thank you baja_van! - you are correct re weight of CO vs Air. CO is very slightly lighter than air. I have been misinformed on this fact!

"Air is made up of 78% Nitrogen and 21% Oxygen - Nitrogen has a weight of 28.013 while Carbon Monoxide (CO) has a weight of 28.011"

Placement: https://www.epa.gov/indoor-air-quali...oxide-detector

Air/gas movement is going to play a larger role in this case. I would think placement near ones head should be considered. The CO gas stream may not dissipate, but relative gas temperatures would play a role in the movement of the CO throughout the cabin.

doublevan2 · 12-21-2021, 08:19 AM

A nat gas installer told me years ago - not an exact quote mind you because my gray matter has somewhat disappeared over the years but here goes - for every 1,000 BTu's of heat output - you should allow at least one square inch of fresh air to enter your space in order to replace oxygen and/or vent CO2 - cross ventilation would be desirable here also -- seeking any corrections or advise from 1der or BroncoHauler - as their experience is way over my head.

Mind you - your hearing is worth something also - maybe find a location where you wouldn't go deaf should your alarm go off -

arctictraveller · 12-24-2021, 12:56 PM

While "Mr Buddy" type heaters are inexpensive and easy to use, there are issues with the consumption of oxygen, the introduction of moisture, and the occasional shortage of the small propane bottles. Many years ago I was in a van with my girlfriend and a portable heater. After some "exercise" we fell asleep, and I only woke up because I rolled over and sensed oxygen leaking in around the rear door seal, but there was a serious lack of oxygen inside and we could have died. Moisture and oxygen depletion can be solved by providing ventilation, but now your letting your warm air out and bringing in more cold air. In my opinion, a better solution is to install a diesel heater. The Chinese diesel heaters sold in numerous places are inexpensive (currently around $140 for the heater and a complete install kit) and when installed in the van will recirculate the heated air rather than continually heating outside air. They are a bit of work to install, since you have to set it up to use outside combustion air and exhaust to the outside. Never the less, there is no moisture introduced inside, actually, they are great at drying the entire interior, including wet gear etc and ice covered windows are a thing of the past. I've run one for two winters now, and it's been flawless. I just spent a month in temps in the mid to high 30s at night and burned less than three gallons of diesel. Since my van is gas, I had to install the provided fuel tank, but it was quite simple. I don't run it all night, just a few hours in the evening and then again in the morning, instead I use a cold rated sleeping bag. I do have a combination CO/smoke detector too, but its really a toast detector since it goes off every time I make some.

Pntyrmvr · 12-24-2021, 02:03 PM

Mr Heater buddy types are available with Canada/Massachusetts combined spec (yes a strange spec) that shuts off in low oxygen and/or CO situations.

I put the propane/CO sensor on the base of the wall. CO and air are so close in density while propane is much heavier I figure that's the best spot. Must clear our dust bunnies though.

KenInRockwall · 12-26-2021, 10:18 AM

I had the exact thought as you. I recently got a small Mr. Heater unit and CO sensor, both of which were reportedly safe and/or approved for us in an RV. However, after reading the information on the CO sensor/alarm installation guide, I realized it would be futile to use it in my case. "The CO alarm should not be installed within 15 feet of a flame". There is no place in my Sportsmobile to safely separate the Mr. Heater and the CO alarm by 15 feet. Also a note of caution, even though the Mr. Heaters show up as being "catalytic" heaters, they are not. All the ones that I looked into (and the small one that I have) are actually burners. These will reportedly not generate CO, unless the oxygen available to the burner is too low. They will generate CO2. As the instruction say, you must provide adequate ventilation to allow for sufficient O2 and exhaust for the CO2. The bottom line is that I'm not sure with those conditions, the Mr. Heater will actually provide sufficient heat nor be trust worthy for using while sleeping. Although, it can probably be safely used while not sleeping.