WWJ Closeup, October 2026

AJ MERTENS
Vice President, Sales, and Marketing
Centennial Plastics Inc.
Hastings, Nebraska

HOW HAVE SUPPLY CHAIN SHIFTS AND THE BUILD AMERICA, BUY AMERICA ACT IMPACTED PRODUCTION OF GEOTHERMAL LINES?
Centennial Plastics is a 100% domestic manufacturer, using U.S.-made raw materials to produce finished products at our facilities. The BABA Act has benefited several of our product categories, including geothermal, while its incentives have helped further strengthen an already growing market.

HOW DOES THE BULLET™ U-BEND FITTING REDUCE BOREHOLE DIAMETER REQUIREMENTS?
The Bullet™ U-Bend’s narrow width and unique “bullet” shape allow contractors to drill smaller-diameter boreholes, reducing grout requirements and installation costs. Its streamlined design also helps guide the loop smoothly down the borehole, making installation faster and more efficient.

WHAT TESTING PROTOCOLS VERIFY THAT PRE-FUSED EARTH LOOPS MAINTAIN ZERO
LEAKAGE PRIOR TO JOBSITE DELIVERY?
Centennial fuses geothermal loops on custom-built, automated fusion tables with computer-controlled heat cycles and joint pressure. Fusion occurs in a climate-controlled environment for year-round consistency.

WHAT LONG-TERM ADVANTAGES DOES PE4710 RESIN PROVIDE FOR HIGH-STRESS UNDERGROUND THERMAL TRANSFER?
PE4710 is an advanced bimodal polyethylene resin combining flexibility, strength, and exceptional resistance to slow crack growth. It provides higher pressure ratings at the same wall thickness and greater resistance to scratches and rock impingement, important advantages in geothermal applications.

WHAT GUIDELINES DO YOU RECOMMEND FOR FIELD PRESSURE TESTING, BALANCING AIR TESTING VS. HYDROSTATIC TESTING?
The new CSA/ANSI/IGSHPA standard includes updated pressure-testing requirements for ground heat exchanger piping. It recommends short-term testing of individual U-bend assemblies and requires longer hydrostatic testing of completed systems.

HOW DOES FACTORY PRESSURIZATION ALTER INSTALLATION TIMELINES AND MITIGATE RISK?
Pressurization and built-in test caps allow each pre-fused earth loop to be pressure-tested before shipment and again by the contractor prior to installation. This provides added confidence in loop integrity minimizing the risk of leaks or fusion issues after the loop has been installed in the borehole.