Around here our propane guy shows up to refill the tanks without having to be call. He apparently knows how long a tank for any given home on his route should last and just fills them as he makes the rounds. Maybe because it's a new house or because it's been vacant for so long they forgot about you. I'd be talking with the propane dealer to see what can be worked out so you don't run into this again..

that is because when a tank goes dry you get other issues. i honestly don't remember what they are, but there was a big thread about it here or on another forum i visit a few years back. i think they get condensation and can start to rust quickly from the inside, but i honestly don't remember.

we use about 3 gallons a month for our gas dryer. so every 15 months or so i call them up and tell them we are getting low and they send a guy out. the lowest i let it get is about 20%.

I have a 500 gallon tank. I would advise you to just put your home on a two month call list so you don't havea whopper bill or ever run too low. Trust me. Since we put in our tank three years ago, gas has more than doubled. I wish we did solar water now.

Thanks for the advice about refills, but we only have the propane for casual use (fireplaces, grill); we don't heat or cook with it. Because the use is intermittent, I think I'd rather just keep an eye on it. That way, I can call for refill when the price is more favorable.

Hmm good luck with that favourable price thing. I don't think petroleum products are going to go back down significantly at all. Welcome to peak oil.

Kind of a hassle the empty tank thing, I guess things need to be purged etc.

I was getting a bbq tank filled and this guy literally jumped in front of me, he'd proudly left all the valves open, not really sure what he was thinking. The filler gave him a dressing down and by rights should have insisted they were purged.

My one issue with propane is the wastage when filling. I'd like to see some sort of recovery system, after all, unburned hydrocarbons are one of the worst pollutants and one of the biggest causes of visible smog...and they can't be removed from the atmosphere once they're there.

I know of no way that the empty tank would hasten any interior corrosion of the tank. I suspect that the regulation is to check for leaks- which could result in the tank being empty unexpectedly. Leaks would be more likely in the piping between the tank and the house.

The problem with an empty tank has to do with flammable vapors in the tank.

Propane tanks are typically filled to 80% capacity with liquid propane. The remaining capacity is vapor. Since there is no oxygen in the tank, vapors in the tank in any proportion do not increase any hazard. An inspection would have nothing to do with the vapor percentage in the tank.