Sigma Engineering, LLC has been serving the HVAC/R industry since 2009 with specialty products that primarily serve the maintenance needs of the refrigeration technician. In 2017, Sigma acquired the replacement parts business for the Standard Refrigeration products worldwide. These products included Liquid Level Indicators, Chiller Barrell and Condenser Gaskets, Zincs, and Rotolock Service Valves and Adapters. While the business initially satisfied the needs of the current customer base, Sigma quickly realized the need of proper packaging for the wholesaler/distributor customer base. 

Today, Sigma Engineering, LLC is the worldwide leader in replacement caps for refrigeration service valves. Our goal is to be your first source, with the best service, for the OEM and wholesale HVAC/R replacement parts in which we specialize.

We STOCK the products we sell. With a same day shipping rate of 99.6%, we look forward to serving you quickly.