Mass laws now require a CO monitor in every residents. I have two, one in the basement and one outside my bedroom door. It doubles as a smoke detector too and has a verbal (actual voice) warning as well as the beeps. The orginal CO monitors had a short lifespan, due to the sensing element attached to the battery. Both got replaced and ran about $25. Now they are a lot cheaper and last a lot longer. The stand alone electric burners are, at best, not going to be more than 1000 watts and don't really have enough heat output to get a big canning pot boiling, or recovering to a boil after adding the jars. I use one of these elements in my outdoor smoker (Alton Browns clay pot type), and the internal temp barely gets up to a heat where the wood chips slightly smoke. Its cranked up to maximum, and has a big heavy cast iron pot to hold the smoking wood. I can't even use it in cold weather, as it just cools off too much. A vented hood over the stove, will give you a lot more safety if using propane indoors. Propane heat is great for the canners, but as mentioned, is hard to control if your wanting to simmer a batch of jelly or tomatoes.

The older style LP tanks do use an internal left handed thread. The new tanks all have the "OPD" (overfill protection device) and they also have an external right handed "worm" type thread. You have two options: get an adapter at Walmart for about $10.00 or, check the date on the old LP tank you have, if it is twelve years or older, then when you have it refilled they will require you to have it re-certified. It is probably cheaper for you in the long run just to do a tank exchange for about $16-$18 bucks. That way you are good for another twelve years. As far as your question about running the bbq on NG, it won't work without a conversion. LP gas is at a much greater pressure than NG so, consequently the orifices are smaller for LP than NG. You can check with Aussie and see if they offer an NG conversion kit. If not, you can attempt to drill out the orifices by hand. There are some places on this discussion board as well as others on the net that talk about how to do this. If you do that, you can also get a 12' Natural Gas hose with a quick disconnect on the end that would fit (maybe without an adapter) on your existing stub from your house and the bbq. I just picked one up from Home Depot. It was made by Char Broil in the accessory area. In either case good luck and happy grilling. bsbbq

dcarch, depending on what you mean by 'old', I am going to disagree. I suppose I may not have found a competent plumber, but I spent hours with appliance guys and Kitchenaid and Google etc. If by 'old', you meant a 1950s stove, then you probably wouldn't even need a plumber. I suspect the same applies if we are talking some nice expensive open burner modern stove. However, if you are talking sealed burner stoves and needing conversion to propane, it is a different story. Unfortunately, other than a modified pressure regulator, the only gas control one has is the orifice for each burner. You will get a propane replacement kit with supposedly appropriate orifices for your burners. If they are not exactly right to give appropriate flame, you need to find other orifices and most specific sizes are not available. There are special micro drill bits that can be used on undersized orifices and it might be possible to find a plumber with such a kit, but perhaps not. In any case, an appropriate flame will not likely be one that would respond to the movement of your burner knob and you may find that max flame could be reached at a half on position. If you can find a stove built for propae it would be a good idea to get it.

I have no specific units to suggest but I believe I have some useful general advice. First, I suspect that most people here are not on propane and therefore don't appreciate a couple problems. Most of my life was using natural gas but my last 15 years has been with propane and I have not been pleased. I suppose that if you can find a cooktop that IS designed specifically for propane rather than needing conversion, that my issues should not apply. Otherwise, it would be far better to get an open burner cooktop. From pictures of thermador, I assume they are open burners even though they have those star caps on them. My point is that gas not come from a little orifice just below the burner but from something that allows gas to fill the whole burner and gas escapes from each little hole as it would have been done 90 years ago. These open burners should be infinitely adjustable and should likely solve any issues They give control of max gas and air proportion and presumably low gas control too. I initially had a KitchenAid sealed burner. It gave perfect simmer control with complete adjustment of low flame setting in the valve stem knobs. But the high settings and air mix should be set with just the right orifice that certainly wasn't the ones sent in the conversion kit and it took time to get replacements that made things better but certainly not perfect. Whirlpool doesn't have all orifices and gets cranky about continuing to be helpful.