Using Your Grill As A Heating Source is a BAD Idea
We are starting to see a side effect of all the cold weather here in The Panhandle and across the great state of Texas. People are starting to turn towards outside heating devices to warm their homes, and while the premise sounds like a good idea. These devices contain a hidden danger while being used inside. Carbon Monoxide. And we see this countless times over the winter. granted the story here is from a few years back, it's one that repeats yearly in a "insert place here" situation:
Carbon Monoxide or CO is odorless and colorless but its effects can definitely put you in a bad place or even worse. CO poisoning presents very similiar to the flu, with fever, aches and vomiting and officials here in Amarillo are also seeing calls for this type of sickness.
Let's get back to basics - Your Grill isn't a heater
Grills aren't meant to heat homes, doesn't matter weather its clean burning propane that would make Hank Hill proud or Charcoal or Natural Gas. These are meant to be used in a well ventilated outdoor space where any Carbon Monoxide (and smoke for that matter) can escape safely into the air. Same is true for your firepit. leave it outside. Not even an option.
Neither is your stove
So the next thing, you might figure if you can't use the grill how bout the stove, that's an inside appliance right? Yes, it is designed for inside use but it presents a different sort of danger. Many of us have a similar setup where we have cabinets or a microwave above the range. As these items heat up they present a fire danger. The cabinets get bone dry and with enough heat build up they do eventually catch fire.
Or your Car
What about my car? Can't I just sit in there with the engine running in the garage? Absolutely not!!! in an un ventilated garage you're a goner quick. Not worth it. Now out in the driveway outside with a breeze... knock yourself out. But remember you only have so much gas.
Your fireplace is cool if it's in good shape
Your fireplace is the best option if you have one but again safety is a factor here too. make sure you have a functioning screen to catch popping embers that could ignite items near the fireplace and your hood is open to properly ventilate out smoke and carbon monoxide. Just make sure you have plenty of firewood.
The best recommendation is blankets. lots and lots of blankets, or layers. or find a warming shelter in your area to stay until conditions improve.