How to Remove Valves from 100 lb Propane Tanks - Propane Multivalve Systems

Introduction to 100 lb Propane Tanks

Propane is a popular fuel source for many applications, including heating, cooking, and powering various equipment. The most common propane tank size used in residential settings is the 100 lb tank, which provides a good balance of portability and fuel capacity. In this article, we'll take a closer look at 100 lb propane tanks and discuss multivalve systems and how to "unvalve" or remove valves from these tanks.

What is a 100 lb Propane Tank?

A 100 lb propane tank is a cylindrical metal tank that holds about 100 pounds (or around 23 gallons) of liquid propane fuel. It measures about 4 feet tall and 1.5 feet in diameter. The empty weight of a 100 lb steel tank is approximately 85 pounds. 100 lb tanks are commonly used with propane grills, RV appliances, patio heaters, generators and other outdoor equipment.

These tanks are designed to hold propane in liquid form under pressure. The pressure allows the propane to turn from a liquid to a gas as it's drawn from the tank, providing the fuel source to power various appliances and equipment. The pressure inside 100 lb tanks ranges from about 90 pounds per square inch (PSI) when full, down to around 5-10 PSI when nearly empty.

100 lb propane tanks feature valves on top to control the release of propane gas. They also have an OPD (Overfill Prevention Device) valve designed to automatically shut off the filling process when the tank reaches 80% capacity. This helps prevent accidental overfilling.

Why Use a 100 lb Propane Tank?

Here are some of the main benefits of using 100 lb propane tanks:

• Larger capacity than smaller tanks - Holds enough fuel to power appliances/equipment for 1-2 months.
• More economical - Buying propane in bulk 100 lb quantities costs less per pound than smaller containers.
• Fewer refills needed - Only need to have tank refilled every 1-2 months rather than every few weeks with smaller tanks.
• Standard size - Many propane appliances, hoses and regulators are designed to connect to 100 lb tanks.
• Reusable - 100 lb tanks are refillable for repeated use, unlike small 1 lb disposable cans.
• Portable - 100 lb tanks are heavy but can be moved by hand trucks or dollies to various locations as needed.

Multivalve Systems on 100 lb Tanks

Some 100 lb propane tanks feature a multivalve system instead of just a single valve. This allows for multiple propane appliances or equipment to be connected to the same tank simultaneously. There are a few main types of multivalve systems found on 100 lb tanks:

Dual Valve 100 lb Tanks

Dual valve 100 lb propane tanks contain two main valves on top of the tank. This allows you to have two points of connection for hoses and regulators. For example, you could have your propane grill connected to one valve, and a patio heater connected to the second valve. Dual valves provide more flexibility in fueling multiple propane appliances from one tank.

Tri/Triple Valve 100 lb Tanks

As the name implies, tri or triple valve 100 lb propane tanks have three valves on top. Tri valves allow connection for three propane devices or appliances at once. Often one valve will be slightly larger (e.g. 1/2" NPT opening) than the other two valves (e.g. 3/8" NPT opening).

POL Valve 100 lb Tanks

POL valves (Parallel Opening Load valves) have two or more smaller valves clustered together in a rectangular formation. Having several smaller valves allows for connecting multiple low-draw propane appliances like lanterns, stoves, etc. POL valves may have anywhere from 2 to 12 smaller valve openings.

Propane Tree Manifold Tanks

Propane tree manifolds provide 4-12 connection points on a tank via a branching "tree" of valves extending from the top. This type of manifold system is ideal for connecting a large number of small propane appliances simultaneously. Often used with food vendor trucks, community event cooking, or places running multiple small propane gear.

In most cases, specially-made propane hoses with the matching valve connections are required to hook appliances up to 100 lb tanks with multivalve systems. The benefit of having a multivalve tank is the convenience of fueling several devices from one centralized propane source.

How to Remove Valves from 100 lb Tanks

There are situations where you may need to remove or "unvalve" the valves from a 100 lb propane tank. Common reasons include:

• Converting to a different valve type - Switching from a single to POL/tree manifold valve system.
• Replacing damaged/leaking valves - Fixing valve issues to make tank safe and usable again.
• Inspecting/repairing tank - Accessing the tank interior through the valve opening.
• Scrapping tank - Removing valves to legally scrap an old out-of-service propane tank.

Tools Needed

To remove valves from a 100 lb propane tank, you typically need:

• Pipe wrench or large adjustable wrench
• Propane hose removal tool
• Pipe thread sealant (pipe dope)

Shut Off Valves & Depressurize Tank

Before attempting to remove any valves, first shut off all valves on the tank to stop propane flow. Rotate valve handles clockwise to close. After valves are shut off, use a propane appliance connected to the tank to bleed off residual gas and depressurize the tank. The tank pressure gauge should read zero before proceeding.

Disconnect Regulators & Hoses

Use a propane hose removal tool to loosen and disconnect any hoses or regulators attached to the tank valves. The tank valves need to be free of attachments before removal.

Unscrew Valves

Place a pipe wrench or large adjustable wrench onto the valve you want to remove. Fit the wrench onto the valve body, taking care not to damage any plastic valve handles or knobs. Turn the wrench counter-clockwise to loosen and unthread the valve. Remove valves slowly and carefully.

Use caution when removing valves - residual propane in the tank can escape during valve removal. Work outdoors away from ignition sources. Place removed valves valve-side up to prevent leaks.

Apply New Pipe Thread Sealant

Inspect the valve opening threads after removal. Clean any debris from the threads. Apply new pipe thread sealant like pipe dope to the threads to prevent leaking when installing the replacement valve or plug.

Replace Valve or Install Plug

If simply replacing a defective valve, thread the new valve clockwise into the tank opening. Tighten with the pipe wrench, being careful not to crack the valve housing. Or, install an NPT threaded pipe plug into the opening to seal it until connecting the new valve.

Removing valves from 100 lb propane tanks isn't difficult, but safe handling procedures are a must. Always follow the manufacturer's instructions for your tank's specific valve system. And consult professionals if unsure about any part of the propane tank unvalving process.

FAQs

How do I know if my 100 lb tank valve needs to be replaced?

Signs that a 100 lb propane tank valve needs replacement include: visible damage like cracks/leaks, difficulty turning the valve, the valve not fully stopping the gas flow, or the valve failing pressure tests done when having the tank refilled.

What valves can I use to replace my 100 lb tank valve?

Most standard 100 lb propane tank valves have 3/4" NPT threads. Compatible replacement valves are available from propane parts suppliers. Make sure any new valve matches the threading and outlet PSI rating of the original.

Is it safe to remove a valve from a propane tank myself?

You can safely remove your own 100 lb propane tank valve if you follow proper depressurization, handling, and storage procedures. However, if uncomfortable doing so, contact a qualified propane servicer.

How do I plug the valve opening after removing the old valve?

Use a 3/4" NPT threaded pipe plug, applying pipe thread sealant to temporarily seal the opening. Replace with the new valve once it's received.

Can I convert my single-valve 100 lb tank to a POL or tree manifold?

Yes, you can convert a standard 100 lb propane tank to a multiple valve POL or tree system. This requires removing the single factory valve and installing the desired manifold valve system.