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Propane connections under the dome of a propane tank

Tank Information

Propane tanks are the energy source and supply for many homes, businesses, farms, and much more. The information here is provided as a general guide to your propane tank. Tampering or modifying your propane tank, its valves, or any connections can result in a very dangerous situation.

Fill Valve

This is where liquid propane is pumped into the tank from a delivery truck

Tank Manufacturers Name Plate

Information placed on tank by the manufacturer at the time of fabrication.  This gives all information and specifications pertinent to the tank.  If the name plate is missing, the tank is "dead" and should not be re-filled.  The most important information* for a propane deliveryman or service technician to read is:

  • Serial Number
  • Working Pressure
  • Year Built
  • Water Capacity
  • ASME Code Symbol

Vapor Return Valve

Used to alleviate pressure in a tank during the filling process.  Also known as a vapor equalizing connection.

Percentage Gauge

Used to indicate the amount of propane in the tank. If your propane gauge reads 20% or below...Call Us!

Liquid Level Gauge

Used by the delivery driver to know when the liquid in the propane tank has reached 80%.  This is also called a bleeder valve.

Service Connection

Connection point between the regulator and the propane tank.  The small piece of copper tubing connecting the two is called a pigtail.  Propane gas (vapor) flows out of the tank, through the regulator, and into the piping system ultimately ending up and being used by your heater, water heater, oven, or other appliance.

Service Valve

This is how the flow of propane gas is turned on and off, much like a water faucet.

Relief Valve

This fitting allows propane to escape if the tank is in an over-pressure condition.  Once the pressure in the tank returns to its normal level, the relief valve closes.  Covering or capping this valve (as shown) keeps dirt, trash, and debris from impeding the action of the relief valve as designed.

Evacuation Connection

This is used in the event that the propane needs to be pumped out of the tank.  An adapter is used to hook the hose up to the tank. The propane delivery truck then "pulls" the propane out of the tank with its pump.