Wall Type Pressure Relief Valves

Performance Under Pressure

Installed in the side walls of water treatment tanks, wall type pressure relief valves relieve groundwater pressure on the exterior sides of a tank. This ensures concrete tanks don’t begin to float, which can cause cracking and other serious issues.

Long Live the Mud Valve!
So reliable it's legendary.

Unique Features

1. Machined Seat

Our strong, flat surface lid with resilient to bronze seating outperforms typical rubber to rubber seals, which are very wide and difficult to seal properly.

2. Removable Grate in Wall Pipe

Designed for easy maintenance, the grate can be accessed simply by opening the lid and reaching in. No tools are required!

3. Wall Pipe Extendable with PVC

With the ability to extend to match exact wall thickness, our valve eliminates the need for extra field work.

4. Rubber Gasket Bonded to Lid

Our gasket won't collapse under water pressure because it is bonded to the lid and reinforced by a stainless steel washer.

5. Integral Cast Water Stop

Because our water stop is cast into the wall pipe, we can help prevent water from leaking around the outside of the wall pipe.

6. Stainless Steel Hardware

All hardware on the valve is made of stainless steel so it won’t corrode and bind up the valve.

Wall Pressure Relief Valves


Cast Iron

  • Epoxy coating on valve and wall pipe
  • Machined bronze seat

316 Stainless Steel

  • Machined stainless steel seat

Download Specifications

Download Drawings

Download Installation, O & M


The valve opens as a result of hydrostatic pressure outside the wall of a tank exceeding the inside pressure. The opening action allows water to flow into the tank thus equalizing pressure both inside and outside of the tank.


The valve requires no lubrication. There is no requirement for regular maintenance. Valve seats should be visually inspected for damage when the valve is accessible.


Valves are to be mounted vertically only. Care should be taken to prevent damage to the seats when placing in form and pouring concrete. Cover and grate should be installed in the body, turned a quarter turn, and tested to be sure cover and grate cannot lift off body.


Parts are available by request. Please contact us for more information.

Application Notes
  • How fast can the water table rise around an empty tank? Think of nearby rivers rising or coming through a dike (A factor in calculating how much flow you must allow into the tank).
  • How fast could you pump out a tank that had a high water table around it? (Another factor in determining inflow requirements.)
  • What is your drainage like around and under the tank? How easily can ground water flow to the tank relief valves? (This may influence how many valves you install. Poor drainage may allow any particular valve to drain only a small area around it.)
  • How strong is your structure? What is the tolerance for flotation (pipes, etc.). What is buoyancy of the tank? What pressures from underneath can the floor handle without breaking?

The above is offered only as a starting point in your design considerations.

The permanent nature of these valves should make you consider carefully the brand of valve you install. Troy Valve tank relief valves are a very inexpensive and cost effective way to protect your project. The cost of some floor or wall relief valves will be far less than the cost of losing a tank or basin due to floating.

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