Relief Valve Purpose:
Think of relief valves as insurance against your blower’s performance. They function as blower protection to prevent over-pressurization. Once a certain pressure is reached, the relief valve provides a pathway for the excess air to escape so that the blower does not reach overload – a common cause of blower failure.
Relief Valve Types:
The most common types of relief valves for regenerative blowers and positive displacement blowers are spring-loaded and weighted relief valves.
Spring-loaded relief valves have a spring housed within the relief valve body, designed to open the relief valve once the blower reaching a specific pressure. These relief valves must be set at a specific pressure based on the blower’s necessary performance.
Weighted relief valves consist of a valve body and weighted plates. Each weight placed on the valve body increases the pressure at which the valve will release the excess air. The cap on the top of the valve body is forced upwards as pressure builds.
Selecting a Relief Valve:
How do you know which relief valve is appropriate for your application? Here are a few things to consider.
- Is your application pressure or vacuum? Spring-loaded relief valves can be used in either pressure and vacuum applications; however, weighted relief valves can only be used for pressure.
- To what elements is your blower exposed? Weighted relief valves are made of sturdier materials than spring-loaded relief valves (hard anodized aluminum vs. zinc-plated mild steel).
- What kind of longevity do you expect from your relief valve? The spring within the spring-loaded relief valve does weaken over time. The simplicity of the design of the weight relief valves provides more longevity.
- What is your air volume? Weighted relief valves support a higher volume of air relative to the spring-loaded valves.
- Are you operating at high heat? Heat can sometimes affect the way the spring releases in spring-loaded valves, so weighted relief valves are a better choice for high heat applications.
If you need help selecting the right relief valve for your blower, contact our experts!