A Quick Guide to Relief Valve Maintenance

Too much pressure in a device or system can lead to a dangerous rupture or explosion. Devices like pressure relief valves are essential to help prevent accidents.

Maintaining these devices is also essential. Here is our quick guide to relief valve maintenance.

Why a Relief Valve Matters

Relief devices are designed to allow venting, which helps release the pressure that has built up inside a device. They are meant to be a stop-gap in case other safety devices fail.

A pressure relief valve is essential with vessels or systems that operate by means of compressed air or fluids, such as hydraulics, pneumatics or electricity. Aside from pressure, they can also help control temperature and flow within the system.

Relief Valve Maintenance Standards

In order for relief valves to function (and stave off a possible disaster) they must open automatically whenever a predetermined amount of pressure has been reached. They also need to close once the pressure has been normalized.

There are strict Standards, Codes, and Practices when it comes to maintaining pressure relief valves. The ASME Code (ASME Boiler and Pressure Vessel Code) is the most widely used and accepted of these. 

Although the ASME Code is voluntary, most states have adopted the rules as mandatory regulations. Be sure to research the specific Standards and Codes for your state or county. Failing to be “up to code” can lead to fines and/or legal action.

6 Maintenance Tips for Relief Valves

Aside from using the ASME Code, there are things you can do to ensure relief valves work properly. Keep these 6 maintenance tips in mind. 

1. Check for broken or leaking pilot systems

Leaks and cracks in the pilot system can affect the function of relief valves. Check the tightness of fittings and look for water leaking from the joint.

2. Check for air in the pilot system

Compressible air in the pilot system can result in incorrect pressure readings. Relief valves can even become unstable. If you see an air pocket in the sight glass (above the water level), you’ll need to vent the main valve bonnet.

3. Clean the strainer screen

If the strainer becomes clogged, it can block the water supply and lead to control valve failure. Be sure to keep the strainer screen clean so the valve will open and close as needed.

4. Replace plugged fittings

The small orifices inside pilot systems can become blocked, too. If this happens, drill out the fitting and soak it in a cleaning solution. If that doesn’t work, you may have to replace the fittings.

5. Test the main valve diaphragm

Main valve diaphragms can wear out over time because of mineral buildup. You can perform a simple test to see if the diaphragm is leaking water into the pilot system.

6. Test the pilot diaphragm

If water is dripping or leaking from the control pilot, you have a problem. You will have to take the pilot diaphragm out and replace it.

Use These Maintenance Tips to Prevent Major Accidents

Proper maintenance of a pressure relief valve is essential to avoid catastrophic failures and dangerous explosions. These 6 tips offer a brief guide, but always consult the ASME Code for more thorough recommendations.

If you need to buy pressure relief valves, we can help you find the right kind for your system. Contact CVP Manufacturing for more information about requirements, recommended applications or to request a quote.