I would strongly suggest you get a wall hung or console -VENTED- heater. Unvented heaters are not for more than 4 hours use [with a window cracked they say in the instructions]. Second propane is more dangerous than natural gas because nat. gas is lighter than air and will evaporate but propane is heaver than air and will ‘pool up’ waiting for a spark [boom]. For example putting a propane furnace in a basement is practically forbiden See this for example of wall hung...
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