If you decide to hook up your stove to the 20lb tank, I would move the stove outside to light it the first time. Since the stove has not been used in a while you want to make sure there are no fuel leaks. Sometimes spiders or other insects can crawl into the appliance and partially block the ports or fuel lines. Ask me how I know???
Thanks for all the info. If I get to the point where I have everything ready to hook up, I will certainly take it outside for that first leak check and light off.

I don't expect a 20lb tank will last a long time, but as little as I would use the gas oven/stove in the garage, I would probably get use out of it for the entire winter. Last year I used a 20lb propane tank to occasionally heat up my garage with a Mr. Heater and that one tank lasted all winter.
But your comments got me wondering how long a 20lb propane tank would last hooked up to my gas oven. I asked Microsoft CoPilot AI and this is what I learned...
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The duration a 20-pound propane tank will last depends on the oven's BTU (British Thermal Unit) rating, as propane consumption is directly related to BTU usage. Here's a general way to estimate:
1. A 20-pound propane tank contains approximately **430,000 BTUs**.
2. Ovens usually consume **20,000–30,000 BTUs per hour**, depending on the model and settings.
Using these numbers:
- If your oven uses **20,000 BTUs per hour**, the tank could last around **21.5 hours**.
- If your oven uses **30,000 BTUs per hour**, the tank would run for about **14.3 hours**.
However, keep in mind that usage may vary based on the oven's efficiency, cooking time, and whether it's cycling on and off to maintain the temperature. It's always a good idea to check the oven's manual or specifications for its exact BTU rating.
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Even at the 30,000 BTU's per hour usage, that's still a lot of pizzas I could cook in the oven and heat up the garage at the same time. My Mr. Heater does a great job in boosting the temperature in the garage, but I am thinking a pizza in the oven would be a bonus.