Propane Freeze Point

[B and B]

Hello All,

A fellow board member posed a question best answered by those in the know.

What temp causes propane to stop flowing properly?

My answer is Propane when a gas feed will not freeze but high flow can cause the regulator to freeze.

Normal TT use of standard tanks should not be an issue.

Also travelling in south many years ago a 30 lb tank was refilled with Butane/propane mixture as opposed propane and froze up north.

Is this still true?

[Wobbles]

I have had a 20lb bottle connected to a double head heater mounted on top, not work this winter. The bottle was full but acted like nothing was in it. Checked it later when the temps got into the 40 degree range and all was working again.

I am in the St Louis, Mo area. What is up?

[heavynlori]

We had same problem with two 100# tanks hooked to run one of those ventless wall heaters....

Used to shut itself off during night and we had a heck of a time getting it to relight most times

Gave up and took it out and put in wood stove

The problem was the tanks/regulator got too cold outside and no flow to heater....figured it out one day when sun beat on tanks later in day and it worked fine - too late, we already gave up fighting it 😁


Sent from my iPhone using Forest River Forums 🇺🇸

[Bama Rambler]

Propane will stop vaporizing at -44ºF, so at that temp you won't get any gas flow even if it was in a open vessel. However, as it gets close to that temp the vapor pressure lowers toward atmospheric so an appliance that requires a large flow (i.e. furnace) can be starved enough that it won't be able to operate. The smallish regulators and gas plumbing in our RV's adds to the problem.

I've never actually tested it, but I'd suspect that somewhere about 10ºF below zero is about as cold as the furnace will operate.

Having said that, the volume of liquid in the vessel has a lot to do with how fast the vaporization occurs and exacerbates the flow problem at low temps.