Mar-26-2015 01:35 PM
Mar-29-2015 09:20 AM
Mar-29-2015 09:02 AM
dougrainer wrote:RinconVTR wrote:wnjj wrote:
The reason for not filling the garden sprayer to 100% is a functionality one. The reason for not filling the LP to 100% is a safety one. They operate on completely different principles.
No sir. They are the actually pretty similar in principle.
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure. Liquid...it doesn't compress, remember? And LP will not remain a liquid, unless its under pressure. It requires a volume of "air"...under high pressure...for the tank to function.
SO that 20% is not just there for thermal expansion (safety), its there for pressurization as well. Just like the garden sprayer.
And that 20% is not a magic number, it can be much lower for these tanks to operate, don't get me wrong. The expansion rate of LP is very high. The US has very strict, protective rules, as we all know.
THERE IS NO AIR IN A LP TANK/CYLINDER. There is only LP vapor that is produced from the LP liquid in the tank. Soooooo, for a 100% full liquid tank, there is NO ROOM for the Liquid to vaporize. As I stated, 100% liquid will cause Liquid to flow OUT when the tank valve is opened and that will destroy the LP regulator. Doug
Mar-29-2015 07:17 AM
Mar-29-2015 07:03 AM
RinconVTR wrote:wnjj wrote:
The reason for not filling the garden sprayer to 100% is a functionality one. The reason for not filling the LP to 100% is a safety one. They operate on completely different principles.
No sir. They are the actually pretty similar in principle.
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure. Liquid...it doesn't compress, remember? And LP will not remain a liquid, unless its under pressure. It requires a volume of "air"...under high pressure...for the tank to function.
SO that 20% is not just there for thermal expansion (safety), its there for pressurization as well. Just like the garden sprayer.
And that 20% is not a magic number, it can be much lower for these tanks to operate, don't get me wrong. The expansion rate of LP is very high. The US has very strict, protective rules, as we all know.
Mar-28-2015 08:23 PM
Mar-28-2015 08:13 PM
Mar-28-2015 08:02 PM
RJsfishin wrote:red31 wrote:RinconVTR wrote:
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure.
Baloney.
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Bull is right !
If ya don't have the foggiest idea what yur talking about, its much better to just stay out of it all, and not look so stupid.
Mar-28-2015 06:51 PM
RJsfishin wrote:Easy there guys. Everyone knows that is why you need a dual tank system and crossover regulator. The second bottle is to keep the first bottle pressurized. 😉red31 wrote:RinconVTR wrote:Baloney.
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure.
-----------------------------------------------------------------
Bull is right !
If ya don't have the foggiest idea what yur talking about, its much better to just stay out of it all, and not look so stupid.
Mar-28-2015 06:46 PM
red31 wrote:RinconVTR wrote:
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure.
Baloney.
Mar-28-2015 03:34 PM
Mar-28-2015 03:33 PM
Mar-28-2015 03:07 PM
RinconVTR wrote:
Go ahead and fill an LP tank 100%, it will not be functional for long due to lack of pressure.
Mar-28-2015 02:11 PM
wnjj wrote:
The reason for not filling the garden sprayer to 100% is a functionality one. The reason for not filling the LP to 100% is a safety one. They operate on completely different principles.
Mar-27-2015 03:33 PM
RinconVTR wrote:wnjj wrote:RinconVTR wrote:sato4000 wrote:
My RV dealer said he will fill up the propane 100 percent if you want.
Impossible.
For perspective...take a pressurized garden sprayer. Fill it to the brim, 100% filled. Then try to add air pressure and spray. You might get a drip of water, if your lucky.
Same principle here with LP tanks, but there are yet more reasons as to why 80% max fill is standard, and already mentioned.
The garden sprayer works nothing like your LP tank. With the garden sprayer, you need air that is compressible to store the pressure needed to push water out the hose.
LP boils at -44F so it wants to convert to gas and flow out of the hose, all by itself. There's no pressurized air helping to move the LP along.
The 80% is for thermal expansion.
I was hoping that when I started my post with "For perspective...", using the reference as only a crude example to help others understand 80% fill issue...would not be taken as a claim that pressurized water tanks are the very same as LP tank.
Mar-27-2015 01:58 PM
red31 wrote:
An overfilling prevention device must not be the primary means to determine when a cylinder is filled to the
maximum allowable filling limit.
NFPA 58, §7.4.4.1
Overfilling Prevention Device [“OPD,” “stop valve”]. A safety device that is designed to automatically prevent a
container from being filled beyond its maximum permitted filling limit.
NFPA 58, §3.3.49
Fixed Maximum Liquid Level Gauge [“outage gauge,” “spitter valve,” “spew gauge”]. A fixed liquid level gauge that
indicates when the liquid level in a container has reached its maximum permitted filling limit.
NFPA 58, §3.3.29.2
The formula for filling LP-gas containers by weight is as follows:
(1) Determine the propane capacity in pounds by multiplying the total water capacity in pounds by 0.42.
(2) Add the tare weight of the cylinder to the liquid weight of the product plus the weight of the hose and
nozzle. The total weight of these three is the proper scale setting.
LP-Gas Safety Rules, §9.136(a) (TEXAS)