Introduction to SORIT Valves

Photo Courtesy of Parker/Sporlan

There are many brands and styles of evaporator pressure regulating valves (EPR), but none as common as the Parker/Sporlan SORIT and ORIT valves.

The diagram above clearly shows some of the common applications. An EPR or “hold back” valve maintains a set suction line pressure and, therefore, coil temperature. That is critical in situations where multiple evaporators of different design temperatures connect back to a shared suction header, common in grocery store refrigeration.

The EPR valve “holds back” pressure in the evaporator to a set pressure so long as there is a pressure differential between the evaporator coil and the shared suction header. The suction header must have a LOWER pressure than the lowest design pressure of any evaporator connected to it.

A SORIT valve is an EPR valve or ORIT (Open on Rise of Inlet Pressure) valve that also includes a solenoid stop.  The purpose of the solenoid stop is to prevent the defrost gas from entering the suction line and overheating/overloading the compressors when the defrost solenoid opens and back feeds the evaporator to defrost.

For a full and detailed explanation of ORIT and SORIT valves, you can read BULLETIN 90-20 from Parker/Sporlan.

—Bryan

 

Related Tech Tips

A Simple Piping Practice
Although there are various line lift, sizing, and trapping guidelines depending on oil and refrigerant type, there is one guideline we can all understand easily and remember to apply. This guideline is to slope suction lines towards condensing units/compressors. Keeping the suction line sloped toward the compressor, especially with long overhead lines, helps return the […]
Read more
How to Replace a Condensing Fan Motor
Service calls about condensing fan motor failure are quite common. Even though fan motor replacement is a standard procedure for residential split systems, it requires careful attention to safety and detail.  This article will give you a step-by-step guide to replacing condensing fan motors. Along the way, we will also explain a few best practices […]
Read more
How to Keep From Getting Bored at Work
Almost nothing is as de-motivational and soul-sucking as boredom and complacency, and there is often no other place that we experience as much monotony as our work. Here is my top list of four ways to keep from dying of boredom in business. 1. See the Art in Your Work Many of us may be […]
Read more

One response to “Introduction to SORIT Valves”

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

loading

To continue you need to agree to our terms.

The HVAC School site, podcast and daily tech tips
Made possible by Generous support from