20lb Propane tanks with 15-18lbs and OPD

[Fast_frank_d]

Hey all, I used to have 20lb propane tanks that I got refilled with 20lbs. Then they expired, and I could not find a convenient re-certification place, so I exchanged them for Blue Rhino tanks with 15lbs in them. I took the Blue Rhino tanks to the refill place, and they could NOT get any more propane in, suggesting that they were not just "under-filled", but the OPD was actually set to 15lb. For long trips, I want 20lbs in my tanks, so here are my questions, hopefully in order of simplicity:


1.) Does any major chain exchange tanks with 20lb in them?
2.) Is there a way to identify what "poundage" an OPD is set at by looking at markings on the outside?
3.) Do the new tanks you buy at Lowes or wherever have the OPD setting identified?
4.) Can the OPD be modified or replaced for another one that goes to 20lb?




Thanks!
Frank

[JRTJH]

20 pound propane tanks at Sams Club are $32 and 30 pound tanks (special order) are $48. I'd suspect you'll spend near that much "modifying" your Blue Rhino tank with "upgraded parts". Even if you do it, you'll still be stuck with a tank that "ages out" before a new one will expire.

Now just might be a great time to upgrade to 30 pound tanks for about $100. All you'll need is a new, longer "center screw rod" available at any hardware store.

[Snoking]

I believe all small propane tanks were designed with 10% room for expansion. So a 5gal 20 lb tank normally hold 4.5 +/- or 18 lbs. Tanks are stamped with empty and full weight.

The exchange tank vendors have been ripping people off for years, as their tank are not completely full to 90%.

[Fast_frank_d]

20 pound propane tanks at Sams Club are $32 and 30 pound tanks (special order) are $48. I'd suspect you'll spend near that much "modifying" your Blue Rhino tank with "upgraded parts". Even if you do it, you'll still be stuck with a tank that "ages out" before a new one will expire.

Now just might be a great time to upgrade to 30 pound tanks for about $100. All you'll need is a new, longer "center screw rod" available at any hardware store.




I prefer 20lb tanks for the reduced weight, and so I can exchange with my grill or a convenience store in a pinch (I've encountered refill place empty at the same time I was). I don't have or need a Sam's club membership, so not really worth that cost, but would be interested in knowing if the Sam's 20lb tanks will definitely hold 20lbs.

[Fast_frank_d]

I believe all small propane tanks were designed with 10% room for expansion. So a 5gal 20 lb tank normally hold 4.5 +/- or 18 lbs. Tanks are stamped with empty and full weight.

The exchange tank vendors have been ripping people off for years, as their tank are not completely full to 90%.


My understanding was that the 20lb rating includes that safety margin. 4.2lb/gal x 4.7gal is a complete fill (with vapor margin at room temperature). 19lb fill when it's really hot outside, 18lb fill was the first time the industry started cheating us. I could be wrong though.

[KeithInUpstateNY]

20 lb tanks are also currently 32.99 at Tractor Supply, regular price is 34.99.

As was previously suggested it is generally considered not to be cost effective to recertify 20 pound tanks.

[Eastham]

Rhino tanks say net 15 lb on the paperwork about $19.00 to exchange. I just filled a 20 lb at tractor supply fo $13.40 and got 4.8 gallons.i have also had rhino tanks filled and got 4.8 gallons put in them .just have to make sure they are in date which a lot of rhino tanks are dated 99 or around there.

[NH_Bulldog]

Propane tanks (of any size) should only ever be filled to 80% of stated capacity to allow for expansion of the gas as temperature fluctuates. To help avoid excessive heat gain (and subsequent gas expansion), outside propane tanks are almost always white. Interestingly enough, many of the Keystone units come through with a black plastic propane tank cover, which of course defeats the intent of painting the tanks white.

[travelin texans]

Propane tanks (of any size) should only ever be filled to 80% of stated capacity to allow for expansion of the gas as temperature fluctuates. To help avoid excessive heat gain (and subsequent gas expansion), outside propane tanks are almost always white. Interestingly enough, many of the Keystone units come through with a black plastic propane tank cover, which of course defeats the intent of painting the tanks white.

You type faster than me!
Regardless of size of tank from 1 gallon to 1000s of gallons only 80% fill.

[Fast_frank_d]

Rhino tanks say net 15 lb on the paperwork about $19.00 to exchange. I just filled a 20 lb at tractor supply fo $13.40 and got 4.8 gallons.i have also had rhino tanks filled and got 4.8 gallons put in them .just have to make sure they are in date which a lot of rhino tanks are dated 99 or around there.

I wonder what the deal was with my Rhino tank that my Tractor Supply could not get any more into it? Now I am very confused about that.

Just for excrutiating clarification, are you saying you bought a 20 lb tank at Tractor Supply and then had it filled at Tractor Supply and got 4.8 gal (20lb)? The reason I'm asking is that I have this irrational fear that if I buy a new tank, the OPD will still shut the valve at 15lb.

[notanlines]

Propane weighs 4.2 pounds per gallon. If any of y'all had 20# tanks refilled and they ACTUALLY pumped 4.8 gallons then you reached 20 pounds by any calculations. I'm just sayin'....

[Frank G]

Just did a quick search on OPD valves and found they are specific to tank size and the OPD valve number is stamped on the tank. (very highly regulated) If a refiller is only providing 15 lbs I would think it is a scale shutoff and not the OPD valve stopping the flow.

I learned something today, my local refiller stopped using the scale and the meter stopped at the appropriate number. Now I know why. I always take in empty tanks.

[JRTJH]

I wonder what the deal was with my Rhino tank that my Tractor Supply could not get any more into it? Now I am very confused about that.

Just for excrutiating clarification, are you saying you bought a 20 lb tank at Tractor Supply and then had it filled at Tractor Supply and got 4.8 gal (20lb)? The reason I'm asking is that I have this irrational fear that if I buy a new tank, the OPD will still shut the valve at 15lb.

Your tank may have some residual water in it or a buildup of Mercaptin from extended use. If it's an "exchange tank from Blue Rhino" the previous "renter of the tank" may have filled the empty tank with "heaven knows what" before turning it in. I'd guess that the "fill station" doesn't purge every tank prior to filling, which is probably another reason why they only fill it with 15 pounds of LPG. That way, they aren't overfilling tanks on their automated fill line.

If there's a half gallon of water in the tank, if it's never been purged and if TSC tries to put LPG in the "empty, but partially filled with water" tank, well, they won't be able to get the full amount of LPG per the tare weight.

You might want to weigh the "empty tank" and see if the weight matches the weight stamped on the tank flange. My guess is it's off a couple pounds.

Propane tanks "should be" purged when put into service and at each certification. My guess is your tank needs to be purged so you can start with a 'truly empty tank".

[Fast_frank_d]

Just did a quick search on OPD valves and found they are specific to tank size and the OPD valve number is stamped on the tank. (very highly regulated) If a refiller is only providing 15 lbs I would think it is a scale shutoff and not the OPD valve stopping the flow.

I learned something today, my local refiller stopped using the scale and the meter stopped at the appropriate number. Now I know why. I always take in empty tanks.

I'm learning too. I always thought it was a back pressure shut off when the OPD valve closed, I did not realize about the scale shut off. I'm going to try another refiller with a fresh rhino tank and see what happens.

[sourdough]

I've read this thread and think it's interesting - how much is in a tank; how much goes in the tank; how full do they fill the tank; are Rhino tank replacements less??

Not to be callous but, why do we care? I run out of propane, I go to abc dealer and pay whatever it costs to fill it.... Am I going to dispute it? Ask for a "gallon" price when they have none? Drive down the road for 30 miles to save $1 or 2?

I do think that knowing "gallons" in the tank, "weight" for the tank is very beneficial and something everyone with an RV should know. When you have a "blank" tank of ? gal/weight size it's probably good to know what it "should be" but to fret over, what, $2 max in what goes in the tank? I guess I'm lost on that - and I travel all the time. I know lots of folks fret over lots of things, but for me and LP....I'm out, fill it, thank you. I spend thousands of dollars on vehicle fuel; I need fuel now, you're here, it costs x.....I don't care.

When I was a young boy my dad was anal about finding the "best" gas price. The Cosden station on the route to the next town (with the little balls floating in the top of the pump)_ sold gas for .19 a gallon. He based that for his purchases. We would drive miles, run out of gas, push the car so we could buy gas at the "cheapest" place. They even had places in the "line" where they would go out and fill up with "drip" gas. Done. Not for me.

We have reached a point with fuel prices; diesel (which used to be cheap), gasoline or "whatever" are at what used to be unbelievable prices; propane, in a small tank, 15lb./20lb/30lb., and I pay a buck or 2 more. Sorry guys, I don't care nor will I spend zero time to try to run down a cheap place, at the cost of $5-10 to save $2. As always JMO/YMMV

[Fast_frank_d]

I've read this thread and think it's interesting - how much is in a tank; how much goes in the tank; how full do they fill the tank; are Rhino tank replacements less??

Not to be callous but, why do we care? I run out of propane, I go to abc dealer and pay whatever it costs to fill it.... Am I going to dispute it? Ask for a "gallon" price when they have none? Drive down the road for 30 miles to save $1 or 2?

I do think that knowing "gallons" in the tank, "weight" for the tank is very beneficial and something everyone with an RV should know. When you have a "blank" tank of ? gal/weight size it's probably good to know what it "should be" but to fret over, what, $2 max in what goes in the tank? I guess I'm lost on that - and I travel all the time. I know lots of folks fret over lots of things, but for me and LP....I'm out, fill it, thank you. I spend thousands of dollars on vehicle fuel; I need fuel now, you're here, it costs x.....I don't care.

When I was a young boy my dad was anal about finding the "best" gas price. The Cosden station on the route to the next town (with the little balls floating in the top of the pump)_ sold gas for .19 a gallon. He based that for his purchases. We would drive miles, run out of gas, push the car so we could buy gas at the "cheapest" place. They even had places in the "line" where they would go out and fill up with "drip" gas. Done. Not for me.

We have reached a point with fuel prices; diesel (which used to be cheap), gasoline or "whatever" are at what used to be unbelievable prices; propane, in a small tank, 15lb./20lb/30lb., and I pay a buck or 2 more. Sorry guys, I don't care nor will I spend zero time to try to run down a cheap place, at the cost of $5-10 to save $2. As always JMO/YMMV

My OP referencing "long trips" is a bit vague, I admit, but it's clearly not about the money. More explicitly stated, when camping at 9000 feet and 50 miles from the nearest propane, I want to have the most capacity possible without dragging the extra weight/inconvenience of more tanks through the mountains. Money isn't the primary motive for the thread, but just to maintain factual accuracy for the discussion, the per-unit price of propane for exchange is almost double that of a refill (~$21 per 20lb exchange vs. $12 refill, not just $1-$2 difference)

[xrated]

Exchange tanks will always be more costly, you're paying extra for the convenience

[Northofu1]

I just bought a new 20lb tank at Costco Canada last weekend, when filling I noticed a sign that said by law they can not refill it to 100% full. It was either 85% or 90%. That is new up here.

[German Shepherd Guy]

Propane tanks (of any size) should only ever be filled to 80% of stated capacity to allow for expansion of the gas as temperature fluctuates. To help avoid excessive heat gain (and subsequent gas expansion), outside propane tanks are almost always white. Interestingly enough, many of the Keystone units come through with a black plastic propane tank cover, which of course defeats the intent of painting the tanks white. :ermm:

That is true, we live very rural and so live off of a 1000 gal. propane tank. Full is 800 gallons. The small tanks are white (or some light gray) just to keep the heat down. When we bought our new 26RBPR it had black covers as stated above. :facepalm:
I replaced with white cover. ;)

Also agree with Frank (the OP) about capacity so replaced the 20's with 30's. :cool:

Frank, you can use them on your grill you just have to set them to the side instead of underneath. :D
More and more around here refill places are selling by the gallon instead of by weight. I think rather than worry about how full the 20's are, as per Sourdough, switching out to 30's is the way to go. I don't think the additional tongue weight on the TT is noticeable. I have never noticed but where do Fifth wheels carry their tanks? :confused:
Oak

[chuckster57]

Most fivers have a tank on each side at the front of the unit. My old ‘97 Jayco 323RKS had both on the curb side at the front and 2 batteries on the curb side just behind the axles.

[Fishsizzle]

Most fivers have a tank on each side at the front of the unit. My old ‘97 Jayco 323RKS had both on the curb side at the front and 2 batteries on the curb side just behind the axles.


Yeah thought it was odd my 5th has both tanks on drivers side.

[JRTJH]

Most fivers have a tank on each side at the front of the unit. My old ‘97 Jayco 323RKS had both on the curb side at the front and 2 batteries on the curb side just behind the axles.

My Cougar XLite is configured the same way. Both propane tanks are on the driver's side and the battery compartment is on the curb side. Both are at the very front corners of the trailer.

[gkainz]

My Laredo has both 30 lb bottles on the drivers side front corner and the 1 original battery box right next to it inboard. I added 2 more batteries from there to about amidship.

[sourdough]

My OP referencing "long trips" is a bit vague, I admit, but it's clearly not about the money. More explicitly stated, when camping at 9000 feet and 50 miles from the nearest propane, I want to have the most capacity possible without dragging the extra weight/inconvenience of more tanks through the mountains. Money isn't the primary motive for the thread, but just to maintain factual accuracy for the discussion, the per-unit price of propane for exchange is almost double that of a refill (~$21 per 20lb exchange vs. $12 refill, not just $1-$2 difference)


I get it. I used to do the same thing and needed the max on everything I took to last as long as it could before I made that 70 mile drive to get gas, groceries, ice, LP etc.

I'm thinking though that I would try to go with the larger tanks. They are heavier, but not that much unless you are just loaded to the max.

[BadmanRick]

Propane tanks are federally and state regulated. They are filled by weight with a 10% expansion regulation. Therefore a 20 lb tank weight is actually 18lbs. All new tanks must comply with federal regulations.

[DucBill]

FWIW new unused tanks contain air sometimes under pressure (depending on atmospheric pressure) which must be purged prior to filling, failure to purge will result in reduced propane fill volume. jM2CW from 1st hand experience.

[murfscot]

The 20 lb propane tanks are designed to accomdate 20% expansion when filled with 20 lbs, so there is no reason to underfill your 20 lb tank. In other words, 20 lbs of propane fills the tank to 80% of it's volume, allowing 20% for expansion.

Blue Rhino uses their own proprietary valves, so that you cannot have the tanks filled elsewhere. Then they only fill 15 lbs and charge you a flat rate based on a full tank. If you are willing to trade convenience for a higher cost and a partially empty tank, then I guess it's not a scam (?).

Here's a great write up addressing both issues, and a bunch of other good info about propane.

http://www.elivermore.com/propane.htm

Cheers!

[thefulminator]

I had the same problem once. The tank had not only propane but air in it as well. When the tank was near empty the attendant bled the air out using the vent valve.

The empty weight of the tank should be imprinted on the handle surrounding the valve. You can weigh the bottle with propane in it and subtract the bottle weight to determine the quantity of propane it is holding. See https://modernsurvivalblog.com/preps/how-to-tell-how-full-or-empty-your-propane-tank-really-is/

Last year I purchased a 20lb bottle with gauge for my bbq at Costco for $25. Since it was a brand new tank, I know exactly how much use/abuse it has seen. It won't have to be replaced for 12 years.

[Clays390]

The biggest concern most propane fillers face is overflowing of the cylinder. It appears Blue Rhino has made sure this does not happen by installing an OPD valve that is set for 75% vs 80%.

[Ken / Claudia]

When dry camping I take a extra tank and it is a 20 lber. 2 reasons, when 1 goes empty on the trailer I have a replacement and I can pick it up easier than the 30s. I also leave the tank cover at home so I can see the gauge. I don't know or care if they hold or take XX. I just fill and pay. At the time of the OPD tanks, I paid for 2 20 lbes to be upgraded and recertified and filled. It costs to damn much. Just buy a new tank on sale cheaper. I see the Blue Rhino displays around here, but I just buy and keep my own tanks. About every gas station has propane for sale.

[NH_Bulldog]

The 20 lb propane tanks are designed to accomdate 20% expansion when filled with 20 lbs, so there is no reason to underfill your 20 lb tank. In other words, 20 lbs of propane fills the tank to 80% of it's volume, allowing 20% for expansion.

Blue Rhino uses their own proprietary valves, so that you cannot have the tanks filled elsewhere

First, a 20 lb tank cannot hold 20 lbs of propane, simple basic math with a little physics thrown in. Second, I have not bought a new propane tank for my grill or smoker at home for 20 years. When my tank ages out, I pick up a Blue Rhino, rip the plastic wrap off and use it, fill it, use it, fill it over and over until it needs recertification and then turn it in at Blue Rhino and do it all over again.

[murfscot]

First, a 20 lb tank cannot hold 20 lbs of propane, simple basic math with a little physics thrown in. Second, I have not bought a new propane tank for my grill or smoker at home for 20 years. When my tank ages out, I pick up a Blue Rhino, rip the plastic wrap off and use it, fill it, use it, fill it over and over until it needs recertification and then turn it in at Blue Rhino and do it all over again.

A gallon of propane weighs ~ 4.25 pounds. The 20 lb tank is full at ~4.7 gallons; 4.7 x 4.24 = 20 pounds of propane. When your tank is full, the total weight should be 20 lbs of propane + the tare weight of the tank (stamped on the side and typically ~17 lbs). So, if your tank is truly full, the total weight should be around 37 pounds.

The reason Blue Rhino and others under fill is purely economic. When propane prices skyrocketed, they started putting 15 pounds in the tanks and charging the same price, claiming that they weren't increasing the price like everyone else. They got in trouble for not disclosing this and are now required to note that it's under filled relative to the capacity of the tank.

Cheers!

[B4Keystone]

Original post had OPD (I suspect Over Pressure Device), at 15 Pounds. Lol .
Has anyone checked, lately, the pressure temperature chart for propane?

https://images.app.goo.gl/D1J867nPefZQPXZ88

Being a licensed gas technician in natural gas and propane fuels..... there should be a little screw on the side of tank valves, this port is connected to a dip tube that is at 80% full. (Been a while... but there used to be)
Tanks can be filled until liquid comes out that loosened screw.
If anyone questions you, ask to see their qualifications that allow them to fill your tanks.
Just my opinion and qualified to handle propane in my area.
Qualifications vary greatly.

These days I'd have to go to trailer to verify. Lol

[chuckster57]

OPD-
Overfill
Prevention
Device
?? That’s what I’ve always heard it stood for.

[Dblhack]

I have a 20 lb tank that is about half empty. I planned on going to a local LP place and have it topped off before my trip. (In the past I always just waited until they were empty, but since I am planning on an extended camping trip, I wanted to start with the max LP I could get in one tank).

Are you all saying that I can't top off a half empty tank? Or are you saying that they would need to purge it first and I pay for the full tank after that?

[B4Keystone]

OPD-
Overfill
Prevention
Device
?? That’s what I’ve always heard it stood for.

Omg.... thanks. That never occurred to me.
Makes sense.

[Eastham]

Take it to a refilling station and they will fill it and you should pay for what gas they put in .yesterday I filled at tractor supply and they put in 4.6 gallons @$2.79 bill was $12.83.for 19.5 lbs .I checked on Cape cod and to get a 15lb Rhino exchange it was $21.99.thats a big difference in price to also get 1/4 of a tank less propane at Rhino.15 lbs compared to 19.5 lbs.Both using 20 lb tanks.

[gkainz]

I have a 20 lb tank that is about half empty. I planned on going to a local LP place and have it topped off before my trip. (In the past I always just waited until they were empty, but since I am planning on an extended camping trip, I wanted to start with the max LP I could get in one tank).

Are you all saying that I can't top off a half empty tank? Or are you saying that they would need to purge it first and I pay for the full tank after that?

No - most places will fill it/top it off. Some places may have a minimum charge. The purge is only needed on new tanks that need the air purged out ... once.

[Wingerdinger]

My local gas station is my propane supplier. I asked them once, and I also watched as he told me.. they put the tank on a scale, zero it out, and fill it til it's 20 lbs (or 30 lbs in my case) on the scale.
They also sell exchange tanks, filled by a supplier, and he told me that the supplier only fills those to 15 lbs because by federal law, they cannot bulk transport them full. The price is much higher for an exchange tank for convenience, and there is a statement on the cage that the tanks are 15 lbs.

[chuckster57]

Out here it’s sold by the gallon.

[rhagfo]

Out here it’s sold by the gallon.

Sold by the gallon here in Oregon also, asked a local Propane distributor when getting tanks re-certified about weight vs gallons, he stated weight is "Old School"
I have had 7.2 put in a 30# and 5.1 in a 20# when empty.

[travelin texans]

My local gas station is my propane supplier. I asked them once, and I also watched as he told me.. they put the tank on a scale, zero it out, and fill it til it's 20 lbs (or 30 lbs in my case) on the scale.

If he zero'd the scale, which by the way most of those scales are xx years old & most likely NEVER calibrated, then you most likely did not get 20 lbs, if I recall a 20# empty bottle weighs 4.7 pounds (tare weight stamped on top collar) so 20-4.7=15.3lbs. In your case a 30 lb bottle weighs more & if any left in the bottle you actually paid more for less.
If at all possible always pay by the gallon, better for you, not by the pound, better for them.