Propane Barbecue Tank Pressure Explained

a grill and propane tank on a patio
  • Intermediate

The gas or propane barbecue has replaced the charcoal grill as the most popular BBQ device in the US. Although a propane barbecue cannot give the smoky flavor familiar to users of charcoal, it has many advantages, including the lack of ash and clean-up required by charcoal barbecues. It is also ‘on tap’, so the heat is more easily regulated than with a charcoal burner system.

Propane Barbecue Pressure

Propane is kept in a tank under a great deal of pressure. This arrangement is often referred to as a “barbecue tank”. These are cylindrical tanks that have a narrow bottom rim (which sometimes causes the tank to ‘rollover’ from time to time). As the barbecue uses the propane gas, the pressure dissipates within the tank, sometimes resulting in the flame taking more time to light as the pressure lessens.

Not all propane tanks come with a fuel gauge, but there is one handy tip to finding out how much pressure is left in the tank. Before turning the gas on, pour hot water on the tank (not the hose end). As the hot water touches the side, the cold gas will absorb the heat and by feeling the side of the tank with your hand, you'll be able to tell where the gas level is wherever the side of the tank gets cold.

Pressure in a propane tank can range between 100 and 200 PSI and even higher if the tank is in the sun. The pressure is then reduced and regulated to 6 ounces for residential use at the home, camper, motor home, or outdoor appliances by a low-pressure regulator either on the tank or nearby. Some gas appliances such as a high heat cast iron burner, however, will require a high-pressure regulator to deliver between 1 PSI and up to 60 PSI pressure to the appliance. It is possible to buy pressure gauges so that you can tell how much the pressure is in the tank before use.

Pressure Regulators

hand twisting a propane tank valve

The propane barbecue can use a high-pressure propane delivery system, which requires a high-pressure regulator. This can vary from between 10 and 60 psi (the pressure measurement). Or, you can have a low-pressure delivery system (for propane barbecues up to 50,000 BTU). The latter should be used only with natural gas or propane that is piped in through house pipes or which has been set up to be used in an RV.

Basic hose and regulator kits are low-pressure regulators with a 50,000 to 60,000 BTUs capacity. For any appliances with a rating exceeding 60,000 BTU, another type regulator, adjustable between 0-60 PSI, will be required such as a High-Pressure Regulator, First Stage Regulator, Second Stage Regulator, Integral Twin Stage Regulator, and Appliance Regulators.

Testing for Leaks

It is important to test the propane tank regularly for leakage. Gas under pressure can quickly turn a small hole into an explosion.

1. Firstly, put all burner controls into the ‘off’ position.

2. Then connect the gas supply before opening the gas valve.

3. Spray a solution of soap and water on to all connection points, and look for bubbles – these indicate leaks in the system.

4. If any are found, immediately turn off all gas valves. Then, either tighten the leaking points or replace the propane tank fittings.