ASME Residential Propane Tank

ASME is a certification for tanks that are typically larger and used for home heating or additionally heating and appliances. These tanks are designed for stationary installation thus are not designed to be moved when containing propane. The design and standards are governed by American Society of Engineers aka (ASME). Above-ground Tanks for residential use typically range from 125 gallons to 1000 gallon although there are even larger options.

This article is not about the small portable tanks such as those used for BBQ grills.

Propane pressure within the tank should be between 100 and 200 psi to ensure that the liquid propane gas remains in a liquid state. Normally, the pressure inside a propane tank fluctuates slightly based on the outside temperature.

The temperature of liquid propane is typically around -44°F (-42°C) at atmospheric pressure. This is the temperature at which propane transitions from a gas to a liquid state, known as its boiling point. On a hot summer day, the temperature outside can rise significantly. If a propane tank is exposed to direct sunlight or high ambient temperatures, the temperature of the liquid propane inside the tank can also increase. However, propane tanks are typically well-insulated, which helps to minimize temperature fluctuations within the tank.

You should never paint your gas tank a dark color for safety reasons. Lighter colors reflect heat from the exterior, while darker colors absorb it, resulting in harmful propane expansion. It's important to note that propane tanks are designed to withstand changes in temperature and pressure, and they incorporate safety features to prevent over-pressurization. However, it's still advisable to take precautions to keep propane tanks cool and shaded, especially during hot weather, to ensure safe and efficient operation.

120 Gallon Propane Tank

A standard 120-gallon propane tank is primarily designed for homes with light LP use such as a single hot water heaters or gas range. Other uses can also include powering a range or clothes dryer. They are typically sized around 54.5" tall and 30" in diameter. They hold 96 gallons of propane when filled. These can be considered a vertical tank.

250 & 350 Gallon Propane Tank

Although larger than the 120 gallon option, this is considered a light use tank. They are horizontal and look like a baby version of the 500 Gallon version. They are around 7' 10" long and 30" in diameter holding up to 200 gallons when filled. There is also a less common 350 Gallon version.

500 Gallon Propane Tank

A 500 gallon propane tank is the most common size domestic LP tank for whole house application, especially in the Midwestern United States. It can contain up to 400 gallons of propane. The empty weight of a 500 gallon propane tank is approximately 1000 pounds or more. Depending on the brand, they range from 950lbs to a little over 1000lbs.

• A Manchester brand 500 gallon tank model 500 GAL A-G is advertised as weighing 1062.00 lbs empty.

A full 500 gallon propane tank weighs filled to 80% should weigh more than 2650 pounds.

To comply with the 80/20 rule for propane safety, a 500-gallon propane tank can only securely carry 400 gallons of propane. The 20% of vacant space in your propane tank offers that opportunity for expansion such as that from a hot summer day.

1000 Gallon Propane Tank

This is the big daddy of residential propane tanks. They often look like a couple 500 gallon tanks were welded together. The dimensions are just over 16 feet long and 41" in diameter holding 800 gallons when filled.