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Varec Biogas

Varec (VApor RECovery Specialty Company) began business in the 1930's at its manufacturing plant in Compton, California. Varec was there in the infancy stage of the biogas market in the early 1950's. From the onset, Varec's focus was to deliver Biogas Handling products that suited customers' specific requirements, even if it meant creating the product off the drawing board. Varec initially sold direct to end-users and in the 1970's instituted a Sales Representative Network that catered to Municipal Wastewater Treatment Plants. A select number of Sales Representatives in the United States helped Varec acquire approximately 90% installed base from the 2,500 Wastewater Treatment Plants that utilize Anaerobic Digesters for Biosolids Treatment built between the mid-60's to late 70's. Today, Varec Biogas is 100% dedicated in providing total solutions to the biogas market. In February, 2003, Westech Industrial Inc. acquired the biogas portion of the Varec business from Tyco Valves and Controls, LP Inc.

Emergency Access Relief Manhole Cover

Varec Biogas 221P / PV Emergency Access Relief Manhole Cover

These manholes protect against costly tank rupture or implosion by providing emergency venting from abnormal internal pressure or vacuum beyond the capability of the pressure & vacuum relief vent. These versatile devices also provide quick and easy access for tank inspection and maintenance. Model 221 P provides emergency pressure relief only while the 221 PV incorporates an added vacuum relief valve. Both models feature a hinged cover to ensure proper resealing after venting, and a reinforced diaphragm for durability and reduced leakage.



  • Hinged cover for proper reseating and added safety
  • New seal design minimizes leakage rate to 1 CFH at 90% of setting
  • Available in emergency pressure
  • Emergency Pressure and Vacuum Relief Models
  • Retrofit kit available for upgrading existing units
  • Cast metal cover provides added strength and extended life
  • API 650 or ANSI 150 flange drilling
  • Optional materials available for chemical applications