What is the minimum size propane tank we need?

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BillWarren

New Member
Sep 19, 2021
2
Woodstock, Virginia
We have a 564SS Greensmart 2 gas fireplace powered by a 20 lb grill tank which we had hooked up after the fireplace was installed. It works, but weakly. The flames are small and one of the burners doesn't even light. The fireplace installer says we need a bigger tank to get full performance. We don't rely on this unit for heat, just looks. What is the smallest tank we could get by with and still get a full burn?
 
We have a 564SS Greensmart 2 gas fireplace powered by a 20 lb grill tank which we had hooked up after the fireplace was installed. It works, but weakly. The flames are small and one of the burners doesn't even light. The fireplace installer says we need a bigger tank to get full performance. We don't rely on this unit for heat, just looks. What is the smallest tank we could get by with and still get a full burn?
Call a LP company and ask them, you likely need more evaporation surface area especially when it gets cold since LP evaporates slower the colder it gets. If you got a 200 to 250 gallon tank they would deliver the propane which is nice, you might get by with using a 100lb tank but they are a bear to go get them filled and your supposed to transport them upright too but if you have a truck and some straps you can maybe get by with that.
 
I talked to the major propane supplier in our area and the smallest tank they will install for a heating system is 100 gallons, which seems way more than we need. Plus, they are kinda big and ugly. I tried to explain that, in our case, the fireplace is not really for heat, but was told that is their policy. BTW, our fireplace is rated at 20,500 BTU/hour max, so it is not a gas hog. I found a 30 pound tank online for about $80 that I could take to have filled, but am not sure that would be any better than the 20 pound grill tank I have now. Whaddaya think?
 
Sounds like a regulator or other issue. When you first turn on the gas fireplace it should work as normal, then as the bottle gets heat soaked (or in this case cold soaked) from evaporating the propane the pressure will drop off and the flames will get small, especially if the outside temps are only around freezing. 20,000BTU isn't a crazy amount of usage by any means, many people around here use 40k or 50k BBQ's in winter on 20lb tanks without issue.

Just for some backup on this issue, here is a chart on the evaporation potential of different sized propane tanks. A 20lb bottle should evaporate 36,000btu/hr of propane at 0F.