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What Are Propane Tank Safety Relief Valves?

Written on: April 19, 2021

Learn More About This Important Feature

propane safety valve wisconsinIf you use propane in your southeastern Wisconsin home, you should know about your propane tank and how it operates.

One feature you need to learn more about is the tank’s safety relief valve. All propane tanks, including the cylinders you use for your grill, are required by law to have pressure relief devices that allow for the release of excess pressure inside the tank.

The safety relief valve is designed to protect your propane tank from rupturing in case excess pressure builds up in the tank. It is also called a pop-off valve, pressure-venting valve, or a relief valve.

The safety relief valve is kept closed by a very strong spring as long as the pressure inside the tank is at a safe level. If the pressure in the tank reaches the same amount of pressure of the spring, the safety relief valve is opened. If that happens, you’ll hear a hissing sound coming from the tank as pressure is dissipated. In instances where the pressure in the tank is much higher than that of the spring, the valve will fully open. You’ll hear a pop if that occurs.

Once the pressure is down below the pressure of the spring, the valve closes on its own. If the valve pops open, it may need to be replaced. DO NOT attempt to repair or replace this on your own. This job requires a professional. Contact us to help.

What causes pressure to build up in a propane tank?

Propane is a liquid. It expands in the heat like water does. But propane’s expansion is much greater, 17 times that of water!

That’s why, when we deliver your propane, we fill your tank to 80% full. You may have noticed that and wondered if it was a mistake. It’s intentional. That remaining 20% of space in your tank remains empty so the propane has space to safely expand in warm or hot conditions.

For safe, expert propane tank installation, Boehlke Bottled Gas can’t be beat! Contact us today for your new propane tank. And don’t forget to ask about our reliable propane delivery!