The Role of the Pressure Control Valve in Water Heaters

The water heater temperature valve or pressure control valve is also called the T&P valve. It is the safety feature found on all water heater tanks. The valve must always be in good working order to ensure the water heater can operate safely in the event of extreme pressure build-up. The valve is designed to open temporarily and discharge short bursts of water when the temperature exceeds 210°F. It also releases pressure if the tank gets above 150 psi. Thus, it is vital to locate your water heater tank pressure control valve so you can test it annually and fix any leaks that happen.

Where is the water heater pressure control valve?

The T&P valve is typically located high on the side or on top of the water heater tank. It is connected to a pipe that runs down the length of the tank and stops a few inches above the floor. The main valve consists of a flat, one and one-half inch lever that lifts and lowers when water is released to reduce the pressure and temperature pressure within the tank.

It is recommended that homeowners test the hot water pressure control valve at least once a year to make sure it is functioning correctly. Be sure to know where the valve is located for ease of testing.

Making sure the valve is working

The most important test is to make sure the valve itself is working correctly. If it isn’t, pressure could build up inside the tank and become a safety hazard.

Before testing the valve, make sure a pipe is connected to it that disgorges wastewater to a floor drain or basin below. Lift the lever and listen for water discharging from the tank and coming out of the pipe near the floor. This indicates that the valve is functioning correctly, and the test is successful.

Suppose water will not discharge from the pipe, or the valve lever is stuck in the closed position. In that case, this could mean that naturally occurring mineral deposits are blocking the waterway, thus, rendering the valve inoperable. Never attempt to apply excessive force on a stuck valve. In this case, turn off the water heater and call a plumber at once for valve replacement.

Master Mac 2000

Whether a pressure control valve is needed for a water heater tank or large industries such as a water distributor, Master Mac 2000 will always have a solution for your requirements. Call us today to discuss your needs, and we may have a solution for you. We’ve been doing it for more than 30 years now as one of Australia’s largest privately-owned pneumatic and valve component distributors. Visit our website at

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