I had 2 carbon Monoxide detectors when I heated with propane and they do work. I placed one 2feet off the floor and the other one near the ceiling of the van. I also had both front windows down about 2 inches and that system kept the van vented just right. The alarms did not go off anymore. Ps, the alarm for carbon monoxide will go off way early before you get dizzy or worst case dead, IMHO, always , always have 2 alarms, you may need backup someday.
Because propane relies on oxygen here is why your alarm went off...
[h=3]Combustion Requirements[/h] Three ingredients required for combustion to take place include fuel, ignition and air. Without any one of these three ingredients, combustion will not occur and even still, the ratio of air to gas must be within an acceptable range for combustion to occur. For instance, a mixture made up of equal parts propane and air will not combust when ignition is introduced. With propane, combustion will occur when the gas in air mixture is between 2.2 and 9.6 and is referred to as the "limits of flammability". In other words, 2.2 parts propane and 97.8 parts air is a combustible mixture as is 9.6 parts propane and 90.4 parts air. Combustion will occur anywhere between these two gas to air ratios with the "ideal burn" being about 4 parts propane and 96 parts air (1:24). This ideal ratio is considered to be the most efficient burn of propane gas when used. Complete combustion of propane is evident by a blue burning flame.
[h=3]Incomplete Propane Combustion - Carbon Monoxide[/h] Carbon Monoxide is produced during the incomplete combustion of propane. Incomplete combustion is defined as within the limits of flammability but higher or lower than the ideal ratio of 4 parts propane 96 parts air. Incomplete propane combustion can occur in one of two ways:
- Lean Burn - The ratio of propane to air is less than 4 parts propane. 2.5 parts propane to 97.5 parts air would produce a lean burn. A lean burn can be recognized when flames appear to lift away from the burner and can potentially go out.
- Rich Burn - A ratio of propane to air is more than 4 parts propane. 8.5 parts propane to 91.5 parts air would produce a rich burn. Recognizing a rich burn is very simple as the flames are much larger than they are supposed to be and are largely yellow in color.
Several products of incomplete combustion that are easily visible and if noticed, action should be taken immediately. Visible signs of incomplete combustion include burner flame appearance (as listed above), soot collecting on appliance windows such as that of a space heater and excessive water vapors forming on windows and cool surfaces during appliance operation. Appliance service and adjustment is needed if any of these visible signs of incomplete combustion are noticed.
Propane requires A LOT of air! That is why the window must be open....
