Mr. Heater MH18B Portable Propane Heater - 18,000 BTU Indoor/Outdoor Use for Camping, Garage, Workshop & Emergency Heating (Red)

On an initial test to burn off any possible residual manufacturing related odors, my Big Buddy California approved model, ran for 2 hours and 40 minutes on high in my basement. I had two windows open a bit. The device threw a lot of heat and I didn’t use the heaters battery powered fan. My CO monitor showed nothing, but my eyes were burning a bit, so I did some research on numerous web sites.The byproducts of propane (C3H6) combustion are carbon dioxide (CO2), water (H2O), some nitrogen oxides (NOx) and potentially carbon monoxide (CO), if there is an insufficient source of oxygen present. Low oxygen results in an incomplete combustion causing carbon monoxide.1. Carbon dioxide – Propane produces .139 lbs of CO2 per hour for every 1000 BTU’s consumed. The big Buddy on high (18,000 BTU/hour) emits 2.5 lbs. of carbon dioxide every hour.The average American emits up about 57 lbs of carbon dioxide per day, or 2.3 pounds per hour. The Big Buddy at the highest setting emits just about the same amount of CO2 (2.5 lbs) per hour as an adult does (2.3 lbs).As long as there is sufficient oxygen available, this carbon dioxide production should not be a problem. Keep the minimum required vent (window) opening.2. Water – Any amount of propane that you burn in a space heater will produce approximately 163 percent as much water. So, a two pound run of propane in the heater produces 3.26 lbs. of water, or just over a quart and a half of water. In the dry winter weather, this may be a plus.3. Oxides of nitrogen – NOx emissions do not form in significant amounts until flame temperatures reach 2800 F. Propane flame temperature in air is 1967° F. NOx can be a toxic gas that at lower concentrations is an upper respiratory irritant. Propane produces, variably .036 ounces of NOx per pound of fuel. At the Big Buddy’s propane flame temperatures, NOx seems that it does not appear to present a major problem.4. Carbon monoxide – This colorless, odorless, tasteless and deadly gas is produced when there is an insufficient supply of oxygen during combustion of a fuel. It is imperative that one should open a window to allow for a source of oxygen. The Mr. Heater manual recommends a source vent to be 18 square inches for the Big Buddy. The device also has an oxygen depletion sensor built in to shut down the Big Buddy in the event that here is a lack of oxygen present for complete combustion. An incomplete combustion produces deadly carbon monoxide.For insurance to guard against incomplete combustion, one should have at least one or perhaps two carbon monoxide monitors available. Also, the pilot flame should be predominantly blue with a slight hint of green. The tip of the flame should have a tinge of yellow. If the pilot flame is yellow, it may be an indication of insufficient oxygen present for a complete combustion, or a dirty pilot line tip.On my second test with the mostly cloudy outdoor temperature at 20° and winds at 10 to 20 mph, I opened two windows exposing 40 square inches to the outside. This is double the minimum required amount of vent opening. With the furnace shut off and the inside temperature dropped to 65° in my 570 square foot location, I turn on the Big Buddy to high, without the fan. To my surprise, the temperature rose steadily from 65° to 71° in 45 minutes. A 6° rise. At that point, I shut the heater off and closed the windows. The room took 3 hours to drop back down to 65°. I was more than pleased with this result. My CO monitors showed nothing. However, my eyes still burned.I went back to the computer. I believe I found the answer to my burning eye concern from one source: At combustion, some water and carbon dioxide can combine to yield a weak carbonic acid (H2CO3). Acids can cause a burning sensation to ones eyes, such as someone cutting an onion. The writer ([...]) suggests leaving the room when the heater is working and going back into the room when the heater is turned off. I think I will try this in the future, or I may stay in the room and put eye drops in to flush the acid, if the burning eye becomes troublesome.I am surprised at the volume of heat produced without the fan. I wanted this heater as an emergency back up if a power failure occurs and it does suits my needs. The eye burning problem is not critical to me; however, I wanted to know why this occurs.Yes, I am pleased.I do not know why they sell the adaptor as if it works with this heater. I guess the older version had a built in fan, which of course they do not say this one doesn't have a fan. I bought this and spent more for the heater, and bought the adaptor since they led me to believe it had a built in fan.The Heater puts out a lot of heat, which mostly drifts up. I purchased this for a couple of jobs. I wanted this as and emergency heat backup if my electric heat goes out in the winter. This will not keep my house comfy but should keep it above freezing for a couple of days.The other reason I purchased this, I have a gazebo in my backyard which I have windows on 3 sides that I install in the winter. The gazebo will not hold heat, but the windows block cold air from blowing through, I enjoy setting in there if I have something to blow warm air toward me. That is why I wanted and paid for a heater with a fan, which I obviously didn't get. When it arrived I set it aside thinking I was all set for enjoying my gazebo this winter. When I finally had time after Christmas to go out and hook this up to a 20lb propane tank and relax in the fresh air with a warm breeze! You can understand my disappointment when I looked all over the heater and couldn't find a place to plug in the adaptor they sold me.At that point, I did the unmanly thing and dug out the directions, and schematic. NO FAN, the blowup showed no fan inside at all. I went to my computer and checked to see if they sent me the wrong heater, no, it was the correct one, but now the description is minimal, and says nothing about a fan, but they still have the 12V adaptor listed to buy with it. So I guess they upgraded/downgraded the heater then after selling a bunch of the lower quality ones they changed the description to not say there is a fan.So, as the heater is now, it does create a lot of heat and will probably be worth having if my electricity goes out, and the natural gas is off for my current second heat source, I guess this will be a help. Since that will probably never happen, and this will not help for the main reason I bought it, I guess I just spent a couple hundred dollars for an emergency backup. I will box it back up, and store it in my shed, just in case! I should have tested it when it first came in, but I had no reason to doubt it would work, and definitely no reason to suspect they would remove an important part like the internal fan without letting people know.I have a home in the Sierras, near Bear Valley. The home is all electric (except for a great fire place).Power use to go out occasionally in the winter and never in the summer. Thanks to PGE it goes out all the time (winter or summer) and for longer periods.I got this heater because it can be used indoors and provides enough heat to the warm the main floor along with the fireplace. It worked so well, that I got a second one for upstairs. I still open a window for fresh air, just to be safe. Great product and no problems. I would strongly recommend it, if you live in an area with cold temperatures and unreliable electricity.I like this heater. It is very well built and it’s simple to use. Unfortunately, the manufacturer chose to remove the fan from previous models. BIG MISTAKE.I have the DeWalt competitor to this product. They are similar in specifications and fuel burn rates, but the DeWalt has a fan. The DeWalt heats the air in my garage workshop and makes it quickly comfortable. This unit only keeps you warm if you stand directly in front of it.I’d gladly pay more to have a fan with this unit. Hopefully the manufacturer will rethink removing the fan.Not a "dislike" as such but for an elderly person the weight is significant. Used in a gazebo, even in a strong cold wind, the heat was fully up to expectation.No issue's with product other than it is intended to outdoor use even with carbon dioxide detector. Found this item to be overpriced when you can directly from store for less money.Throws a lot of heat on Max. Tried both 1lb cylinders and 20lb tank. Quality construction throughout. A fan would be a great add-on.Je suis tres content de cette de se système. Fonctionne bien, facile a utiliser. A 18B on sent une tres bonne chaleur.Arrived promptly, Happy with the product.