For the end-user, propane is a safe, easy to use heating source that can power barbecue grills, home heating systems, and even refrigerators. But along the way, from extraction in the field to storage at your local Ferrellgas office, propane undergoes a number of different processes to ready it for commercial and residential use.
The key to propane’s portability, and what packs so much energy into a relatively small volume of space, is pressure. In its natural state, propane is a vaporous gas. Under pressure, however, that vapor is converted to a form that is easier to transport and store. Liquified Petroleum Gas, or LPG, is the result of pressurizing propane gas, which causes it to drop below its boiling point of -44 degrees Fahrenheit.
At this temperature or below, propane remains in a liquid state, which condenses a large amount of energy into a small volume of fluid. When the propane’s temperature increases, it begins to “boil” off and this vapor is the usable form of propane that is converted to flame and heat your appliances. In this state, propane gas has a natural reaction to expand until it reaches equilibrium, or where it has normalized with atmospheric pressure.
There are four “Gas Laws” that explain the relationship between gases, pressure, temperature, and volume. Generally, propane pressure should be between 100 and 200 psi to ensure that the liquid propane gas remains in a liquid state.
> 100 psi Low 100 - 200 psi Normal Range < 200 psi HighNormally, the pressure inside a propane tank fluctuates slightly based on the outside temperature. For example, a standard 20-pound propane tank at 70 degrees will have 145 psi internal pressure. That same tank on a 100-degree day will have 172 psi of pressure.
Propane pressure levels exceeding 200 psi are likely to trigger a release from the safety relief valve commonly installed on propane storage tanks. This device allows propane gas to safely vent out of the tank if there’s excessive pressure.
If a propane tank is in contact with extreme heat, such as a garage fire, the external heat can cause the temperature inside the tank to increase, creating a BLEVE –or boiling liquid expanding vapor explosion. As the heat raises the temperature of the propane, the vapor expands and increases the pressure inside the tank, which can lead to a rupture.
On the other extreme, propane itself is unlikely to freeze –that would require a temperature below -306 degrees Fahrenheit. However, trace amounts of water in supply lines can freeze inside fuel ports and fittings in extremely cold conditions.
To check the pressure on your tank:
On smaller systems, such as propane barbecue grills, it’s important to remember that exposure to direct sunlight can increase both the temperature and pressure inside your propane tank.
If your tank is painted black or another dark, heat-absorbing color, it could further increase the internal temperature and pressure of the tank.
The best practice is to store your grill and tank in a shaded and well-ventilated area. While your tank will be equipped with a pressure relief valve – also known as a “pop-off valve” – in case the pressure rises too high, there’s no need to tempt fate –or waste the propane you’ve purchased.
It’s important to make sure your tank is not damaged and is free from rust, which could likewise affect not only the tank’s performance, but its ability to maintain the proper pressure.
Ferrellgas locations offer tank painting and rust removal services, and qualified technicians can inspect your tank to ensure it’s in good working order. Ferrellgas also produces resources with valuable information about propane tank safety, and additional information that will help you get the most from your tank.
Knowing how much pressure is in a propane tank is important, but it’s only part of the information you need to know to get the most from your experience with propane.
Understanding how your tank – and propane gas – reacts to extreme temperatures, the safety devices available, and the importance of safety and maintenance, will help ensure you get the most from each tank of propane you use. And don’t forget that there’s a Ferrellgas location near you with experts who are ready to help you answer any question.
Propane regulator facts, propane facts, propane 101, high pressure and low pressure, types of propane regulators, and
a word about propane tanks
...Pressure in a propane tank, large or small, can range between 100 and 200 psi...or even higher when the tank gets hot in the sun. This propane tank pressure must be reduced and be regulated for use in a home, motor home, camper, or an outdoor gas appliance. A residential application will require a low pressure regulator which reduces the gas pressure to 6 ounces (10.5 inches water column).This low pressure regulator will be located on or near the main supply tank to the home, motor home, or camper.Outdoor gas appliances may access low pressure propane gas through a gas convenience outlet located somewhere after the low pressure regulator or directly from a portable tank like the kind you see at Home Depot or Lowes. Portable tanks require propane pressure regulation. Sometimes a low pressure regulator is built directly into the gas appliance, but more often is installed on the portable tank itself. Check with your gas appliance manufacturer to see what propane pressure is required for your appliance.
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That is, the propane pressure is fixed at a certain pressure; i.e., 10 psi or 20 psi. Attenuation of the amount of gas delivered to the appliance is done by use of an inline ball valve or needle control valve located either on the hose or built into the appliance.Outdoor gas appliances such as high heat cast iron burners require the use of a high pressure regulator because they need more volumes of gas than a low pressure regulator can deliver. High pressure regulators regulate the output pressure from 1 psi to as high as 60 psi. There are a number of different high pressure regulators available. Some high pressure regulators are "preset" That is, the propane pressure is fixed at a certain pressure; i.e., 10 psi or 20 psi. Attenuation of the amount of gas delivered to the appliance is done by use of an inline ball valve or needle control valve located either on the hose or built into the appliance.The other common type of high pressure regulator is an . Adjustable high pressure regulators are available in 0-20 psi, 0-30 psi, and 0-60 psi versions and have an output pressure adjustment control built directly into the regulator.
Should I buy the highest pressure propane regulator to insure enough gas delivery?
There is no advantage of having a propane regulator with a lot more btu/hr output than you actually need.
Depending on the number of btu/hr that the gas appliance(s) requires, one chooses the adjustable propane gas regulator which delivers the required number of btu/hr. Choose the propane regulator that is the closest match.
As you choose a higher and higher pressure high pressure propane regulator, the degree of control that the propane regulator valve has over the gas output decreases; i.e., turning the valve an 1/8" in a 0-60 psi adjustable propane regulator has a lot more effect than turning the valve an 1/8" in a 0-20 psi adjustable propane regulator. Choose the high pressure regulator which most closely matches your actual btu/hr need.
How long will my portable tank of propane last?
This is easy to figure out if you know the number of pounds of gas that is in your full tank and the btu/hr demand of your burner or other gas appliance. One pound of liquid gas in your tank has 21,591 btu/hr fuel value. The most common tank is a 20 pound tank (also sometimes referred to as a 5 gallon tank). This is the kind of portable tank you would find at a Home Depot, Lowes, etc. If you have a low pressure burner, for example, that is rated at 40,000 btu/hr maximum output then you can run that burner at full blast for 10.8 hours: (20# x 21,591btu/# = 431,820 btu is the gas in a 20# tank, 431,820 btu ÷ 40,000 btu/hr = 10.8 hrs) . On the other hand if you have a high heat, high pressure burner that is rated at 160,000 btu/hr maximum output you can run that burner at full blast for only 2.7 hours. In practice, it is unusual for anyone to run a burner at full throttle for that long so you will probably not empty the tank this quickly. The point is that if you want to develop the heat in an uninterrupted manner you have to plan for adequate propane tank reserves. Experienced chefs keep a spare propane tank handy.
These figures are all theoretical. According to a major 20-pound propane tank producer, Blue Rhino, their 20-pound propane tank will only contain about 4.1 gallons of liquid propane which weighs just 17 pounds. The empty propane tank weighs about 20 pounds so if you add the 17 pounds of gas you have a full propane tank weighing around 37 pounds.
Folks also ask: "What is the pressure inside my portable tank?" According to the publication NFPA58, a tank with 20 pounds of gas at 70°F has a pressure of 145 psi, at 90°F would have 180 psi, at 105°F would have 235 psi, and at 130°F would have 315 psi.
My propane tank and regulator ice up and the propane output is dropping.
Often the source of the problem is water within the small, portable propane tank. Water is not supposed to be in the tank, but usually is. The propane inside the tank is in a liquid form. Propane leaves the tank in a vaporized state. That change of state from liquid to gas requires a considerable amount of heat.The heat to vaporize can only come from the metal tank that contains the gas. If the demand for the propane is very high, the tank and regulator get noticeably colder and colder. If the demand for gas is very high the vaporized propane delivered will decrease. If there happens to water along with the propane stored in the tank, the water vapor will freeze internally at the tank valve and can even freeze within the regulator and will further reduce or block the flow of propane to the supply hose. This is noticed more profoundly when the demand for the propane is at a high level and/or the amount of liquid propane left in the tank is at a lower level. Water does not mix with propane but both propane and water have vapor pressures within the tank. Moving or shaking the tank is not helpful.
What can I do when the propane tank and regulator freezes?
What can you do? Buy the largest tank you can lug around. As the internal surface area increases the heat sink increases because the metal cylinder has a larger heat reserve available. You could also complain to your retail gas supplier. Ask them to purchase the gas from a gas wholesaler that adds some methyl alcohol into the propane. Methyl alcohol acts as antifreeze. Wholesale propane gas suppliers in colder climates often do this in the winter months. If that is not feasible then occasionally pour some hot water over the tank valve and propane regulator. You can try to keep the propane tank and gas regulator in a warm place. The colder the propane tank and gas regulator gets, the more prone the tank and gas regulator will be to experience a freeze up during high propane demands. Lastly, keep a spare propane tank and be prepared to make a switch whenever you sense a decrease in the flow of the propane.
Caterers often like to use a manual tank changeover valve to quickly change to a warm, full tank by the simple turn of a valve. After you switchover to the new tank the other frozen tank can have time to warm back up or you can changeout the problem or empty tank. A freeze up will be more pronounced with a less than half-full or a near-empty propane tank, and occurs more frequently in a smaller 5 gallon propane tanks than a larger propane tank. Experienced caterers commonly use as large of a propane tank as they can and keep a spare tank nearby. The use of a twin stage regulator will certainly help reduce these freeze-ups because the gas expansion process is drawing heat from two separate regulators rather than just one. A twin stage regulator also delivers a more steady and even supply of gas.
What is a btu?
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A btu, or British Thermal Unit, is the amount of energy required to raise one pound of water one degree Fahrenheit.
Recommended article:♦
A gallon of liquid propane contains 91,502 btu's.
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A pound of liquid propane contains 21,591 btu's.
I have a low pressure regulator but it does not seem to supply enough gas for my appliance.
Unfortunately, many of the preset low pressure regulators available in the marketplace use 1/4"ID black hose and most are attached to a propane regulator with only a 1/4"ID NPT (National Pipe Thread Taper) outlet. There is a definite limit to the volume of gas that can be delivered through this small ID hose at a fixed low propane pressure of 6 ounces.
What can I do if my preset low pressure regulator is not supplying enough gas? Can I increase the pressure of the gas?
No, you cannot increase the pressure. The low pressure regulator is PRESET at 6 ounces, which is 10.5 WC or Water Column inches. The likelihood is you are using a preset regulator with a 1/4" ID outlet and a black thermorubber hose which has an 1/4"ID. This limits the volume of gas to your appliance..
The amount of propane that can be delivered to the appliance is increased by a factor of 2.26 so the chances of starving your appliance for propane are greatly diminished. GasHosesandRegulators.com sells only 3/8"ID gas outlet low pressure gas regulators with 3/8"ID low pressure hoses for this very reason. Our grey hose (3/8" ID) carries UL (Underwriters Laboratories), CSA (Canadian Standards Association), and AGA (American Gas Association) approvals and is designed to supply up to about 100,000 btu/hr of propane gas. Don't starve your gas appliance; get a 3/8"ID gas outlet low pressure regulator with a 3/8"ID light gray hose., you cannot increase the pressure. The low pressure regulator is PRESET at 6 ounces, which is 10.5 WC or. The likelihood is you are using a preset regulator with a 1/4" ID outlet and a black thermorubber hose which has an 1/4"ID. This limits the volume of gas to your appliance.Youincrease the volume of gas by using a low pressure regulator with a 3/8"ID gas outlet and a (light grey) gas hose of 3/8"ID The amount of propane that can be delivered to the appliance is increased by a factor of 2.26 so the chances of starving your appliance for propane are greatly diminished. GasHosesandRegulators.com sells only 3/8"ID gas outlet low pressure gas regulators with 3/8"ID low pressure hoses for this very reason. Our grey hose (3/8" ID) carries(Underwriters Laboratories),(Canadian Standards Association), and(American Gas Association) approvals and is designed to supply up to about 100,000 btu/hr of propane gas. Don't starve your gas appliance; get a 3/8"ID gas outlet low pressure regulator with a 3/8"ID light gray hose.
Why does my grill have little or no flame?
According to the Coleman company there are at least three possible reasons:
First is that the propane tank might have been improperly filled. All tanks must be purged of air before being filled with gas. This purging requires filling with a small amount of gas and then emptying. Propane is heavier than air and will force the air out of the tank during the emptying. Filling with gas then can proceed. If the tank is not purged then the air is the first gas to exit the tank and the grill will either have no flame or a very low flame for possibly over an hour until the air does fully exit the tank.
A second cause could be automatic activation of a surge protection device within the propane regulator. If you turn on the tank valve before you fully turn off each of the burner knobs on the grill, the surge protector could sense a leak and activate. The fuel flow will be reduced. The remedy is to turn everything off, disconnect the tank, and reconnect everything before starting over.
A third possible cause might be that the tank was overfilled. All propane tanks are now fitted with Overfill Protection Devices (OPD) which is designed to be activated by a float valve. The OPD feature prevents overfilling of the tank by shutting off the valve. A 20% empty space is necessary to prevent the tank from venting large amounts of propane when the ambient temperature rises. This OPD can also be inadvertently activated by tilting a very full tank during moving.
Interesting Facts
One gallon of water weighs 8.33 pounds. It takes one btu to raise each pound of water 1 degree Fahrenheit or 8.33 btu's to raise one gallon of water one degree Fahrenheit. Knowing that, it is simple to calculate the number of btu's required to raise a known number of gallons of water to boiling...(assuming 100% thermal transfer of the heat from the flame and knowing the starting temperature of the water). This is useful in determining approximately how long your tank of gas will last.
What is the better fuel, Propane or Natural Gas?
Volume to volume propane delivers more btu/hr than natural gas.
For example, at 60 °F a flow of 1 cubic foot/hr of natural gas will deliver 1030 btu/hr but 1 cubic foot/hr of propane will deliver 2488 btu/hr...about 2.5 times more heat. The reason for this is that methane (natural gas) has one carbon atom bound to four hydrogen atoms and propane has three carbon atoms bound to eight hydrogen atoms.The oxidation (burning) of a propane molecule releases 2.5 times more heat because the process is breaking many more chemical bonds within the molecule. The end products of the complete oxidation (burning) of both a natural gas molecule or a propane gas molecule are the same, carbon dioxide and water. The difference is that you get a lot more carbon dioxide and water with the burning of the propane and, of course, a lot more heat.
Natural gas is a reliable and cheap fuel. Many people opt for it if it is available. Propane is the more practical choice if your have a mobile cooking setup. Our low pressure cast iron burners, pipe burners, and jet burners can be configured with different size orifices to give the same BTU/hr output regardless of which fuel you choose.
More propane 101
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A 20# LPG tank theoretically contains 4.72 gallons but in practice may only contain 4.1 gallons since gas cylinders are not supposed to be filled more than 80% full.
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One psi equals 27.7 inches of water column.We provide these propane regulator facts,facts, to help take the mystery out of choosing the right high pressure regulator or low pressure regulator If you learned something on this page and it was of help to you please
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