TIP #2: Verify the Correct PRV Size to not cause valve wear and erratic pressure control.

Installation of an oversized PRV will often cause increased valve wear and erratic pressure control. The selection of the proper PRV should be based on the supply pressure, delivery pressure, and amount of steam required to be delivered to the downstream side. It should NOT be selected solely on the size of the supply line. For example, a 2” steam supply line does NOT necessarily call for a 2” pressure reducing valve. In fact, in most applications, a 2nd PRV would be larger than needed to provide proper pressure reduction on a 2″ line.

Installation of an oversized PRV will often cause increased valve wear and erratic pressure control.

In order to maintain a desired pres­sure reduction, the oversized PRV must be kept in a throttled (almost closed) position. This “throttling” of the valve to maintain downstream pressure can lead to excessive wear and steam cut­ting of the valve or seat which results in increased maintenance costs. (An oversized PRV can often be identified by a “chattering” sound that occurs when the throttled valve repeatedly strikes the valve seat.) CONTINUE TO Remember Seasonal Steam Load Variations – Steam System Troubleshooting Tip #3 >>