Ventilation

[rndrifter]

I've got a 6 x 14 enclosed trailer that I've built out inside as a travel tailer. It has one of those roof vents that is the standard crank vent on the roofs of these trailers. I've got the trailer sealed air tight, so it's the only vent..

In the summer, I leave it cracked about 4-5 inches for ventilation. I have a little window shaker and it keeps the trailer nice and cool even during the day. The ac does not exchange air with the outside.

The cool air sinks, so I don't worry about the vent at the top. I've noted no ill effects, so I'm obviously getting enough air exchange.

In the winter, however, I'm a bit more concerned because the heat rises, and the vent at the top may make it very cold inside and make heating difficult. So I'd like to have as small a hole as is safe, in order to conserve heat.

So the question would be theoretically, if you had a man in a sealed box, how large of a hole would you need to support air exchange? It wouldn't be the lack of oxygen that's the immediate issue.. it would be the buildup of CO2 inside, which would kill you long before you ran out of air.

Any input appreciated.

[rndrifter]

westend wrote:
I guess you bought alarms that sense both CO and CO2. I've never seen a CO2 (only) alarm but they may exist.

One thing I did for my propane heating appliance was to duct in both combustion air and flue make-up air. That makes the pressure balance in the cabin stay more towards the positive side.

In a real small space like your trailer, it may be a good thing to have a fresh air vent close to the floor, also. A PVC pipe used as a duct can be easily controlled by a plastic irrigation valve. The pipe is also fairly easy to seal against the siding.

I'm going to use electric heating, possibly using my generator if I need to run a little heater. I'm only going to be staying in my trailer in the day, since I work nights. I wouldn't dream of running any sort of fuel burning device inside such a small space.

[Boon_Docker]

The OP is talking about CO2, the stuff you exhale from your lungs.

[Dutch_12078]

If you're using an actual RV propane furnace, there is no transfer of combustion products to the inside as long as the heat exchanger is in good condition. The inside air is simply cycled through the exchanger, similar to an air conditioner. A fresh air vent and a good CO detector is still recommended of course, to insure a safe air quality.

[westend]

I guess you bought alarms that sense both CO and CO2. I've never seen a CO2 (only) alarm but they may exist.

One thing I did for my propane heating appliance was to duct in both combustion air and flue make-up air. That makes the pressure balance in the cabin stay more towards the positive side.

In a real small space like your trailer, it may be a good thing to have a fresh air vent close to the floor, also. A PVC pipe used as a duct can be easily controlled by a plastic irrigation valve. The pipe is also fairly easy to seal against the siding.

[rndrifter]

Well, I thought about it and it's just too important to take a chance with, so I bought a CO2 monitor (actually 2 of them - one for rv, one for my house). I'll report back with my findings :).

In my reading, I've seen where others are surprised to find their CO2 levels very high in their homes, especially small offices, etc.

Not good, and I'm going to be proactive here!