A warning about Propane gas: Propane is heavier then air and can sit on your floor all around your boiler and or furnace or water heater, and can explode when you go to light the pilot light, and if that is not bad enough it can, and does, loose it's odor, making it impossible to detect and an extremely dangerous situation.
Natural gas can build up in a room and can explode. it has lifted houses off of there foundations. I'm not trying to scare you, Gas appliances are perfectly safe under normal operating procedures. The danger comes in when someone who does not know what they are doing messes around with them, changes settings or removes safety items that are required.
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