Does # of Brews on Propane Tank Decrease in Cold Weather?

[Doc Robinson]

Historically, I have been barely getting 2 brews on a tank of propane using a Banjo Burner. I've been brewing in ambient temperatures from 30 - 50 degrees.

Before my last brew, I realized that the spring for the air flow plate should be on the outside (not the inside like I had it) so that it pushes the plate flush against the neck of the burner. I think I was getting way too much air in the mix.

My tank shows a weight of 18.5 + 17 pounds of propane (35.5 pounds total) and I've used it for one brew. It now weights 31 pounds. That would indicate that I only used about 1/4 tank last time, so I think adjusting the plate may have fixed the problem.

My question still remains, do you notice that you get fewer brews on a tank in the winter than in the summer?

 

[BioBeing]

Before my last brew, I realized that the spring for the air flow plate should be on the outside (not the inside like I had it) so that it pushes the plate flush against the neck of the burner. I think I was getting way too much air in the mix.

Huh! I didn't know that...

I was getting 3 or 4 brews I guess, from a brinkman burner. Just got an SP-10, and I'm pretty sure I put the spring on wrong. The only bit I had to assemble, and there were no instructions...

 

[caspio]

I don't really think it changes how much propane you consume, other than having to put out more BTUs to combat losses to ambient. If anything, colder weather conserves propane. Propane is stored as a liquid inside the tank, and it needs to take on at least some heat to transfer to a gas. In cold weather if I'm cranking the burner, sometimes I have to rotate between two tanks because they lose so much pressure the flame drops to 1/4 of what it should be. Once, I even managed to freeze a tank to my brew stand - it wouldn't come off the shelf it rests on.

 

[adx]

There is something wrong with only 2 brew out of a tank. Like your latest batch, I can get 4 brews from a 20 gallon fill.

The only difference with cold weather is that it will stop pushing out a good pressure once the tank starts to freeze. Once that happens the pressure out of the tank gets lower and lower.

 

[jspence1]

I would assume that it would take more propane in colder weather. you'll be losing more heat so you'll have to put more in to boil. will it be a lot probably not but more yes

 

[Doc Robinson]

I'm going to blow a space heater on the tank. I even have sheets of 2" hard styrofoam that I could make an insulating box out of.

 

[bendavanza]

I've seen people put their tanks in a water bath for cold weather brewing.

 

[shortyjacobs]

Woah folks.

The problem is the cold weather increases heat loss from the kettle/burner, NOT from the tank. No need to heat your tank...Propane has a boiling point, (where it turns to the gas you burn), of -43 degrees F. That's NEGATIVE 43. Unless you are brewing in Antarctica, you are fine.

Shield your burner/kettle assembly, that will help, but don't worry about the tank itself.

Still, 2 per tank is terrible. I get 6-7 5 gal brews per tank, (all grain, so heating mash/sparge water too).

Edit: Others are right though, your pressure pushed by the tank will drop at cold temps, as boiling propane costs energy that it has to pull in from outside, and if outside is cold there isn't enough delta T to make that energy transfer happen quickly. Still, unless you are worried that your flame isn't big enough, (and once I am boiling, my gas is only at about 1/5th wide open) heat shouldn't be required....as one person said, cold will help you CONSERVE propane if you typically run wider open on the gas than you need to.....

 

[teach]

I got 6 five-gallon batches out of my last propane tank. Four of those were all-grain, and two were extract / partial mash. I'm now using an electric HLT, though, so I expect to get more batches out of the current tank. I've done five so far, and the tank still weighs 23.5 lbs.

Just my two cents.

-g-

 

[Doc Robinson]

There is no chance I'll ever get five. I brewed a 10 gallon batch today and used 7 pounds of propane.

 

[2-0turbo]

Woah folks.

The problem is the cold weather increases heat loss from the kettle/burner, NOT from the tank. No need to heat your tank...Propane has a boiling point, (where it turns to the gas you burn), of -43 degrees F. That's NEGATIVE 43. Unless you are brewing in Antarctica, you are fine.

True, but performance (BTU/hr) suffers in the cold temperature. And, at -43F, the propane just sits there as a liquid. There is no vapor pressure--zero. No problem throwing the propane tank in some hot water--that helps, but honestly, it almost has to be a trashcan of hot water and the tank will pull the heat out of the water quite quickly. Just like the AC guy who throws the 30-lb container of freon in hot water when charging your AC.

I have a friend who flys hot air balloons. When the weather is cool, he will pressurize his propane tanks with a nitrogen tank he keeps, up to I think 120 or 140 psi--I can't remember. He does this on the ground and just gets the pressure up. You figure, if it is freezing out (32F), the vapor pressure of propane is only 25psi. Not a lot of pressure. This is acceptable per the manufacturer and helps keep the burners happy on a cold morning. For him, it's not the problem with the beer taking longer--he might end of going down when he'd rather go up! : )

 

[2-0turbo]

http://www.engineeringtoolbox.com/propane-vapor-pressure-d_1020.html Oops, I quoted the wrong pressure. 0°F is about 25 psi. 32°F is about 55 psi.

 

[GNBrews]

And remember that if it's 32F ambient, the tank is only going to get colder as propane is used. You might start out with 55PSI of tank pressure, but it's gonna go down quite quickly as the liquid propane turns to gas in the tank.

To solve that problem, I keep the tank close to the boil kettle burner to utilize the wasted BTU's.

 

[shortyjacobs]

And remember that if it's 32F ambient, the tank is only going to get colder as propane is used. You might start out with 55PSI of tank pressure, but it's gonna go down quite quickly as the liquid propane turns to gas in the tank.

To solve that problem, I keep the tank close to the boil kettle burner to utilize the wasted BTU's.

Hah, I was brewing this past weekend, and apparently kept the tank way too close to the burner. I noticed that the condensation was only on half of the tank, (the half away from the burner). The part of the tank closest to the burner was too hot to touch!!!! :cross: