Sisco P/T Plugs
The industry's first polyethylene fusion expansion tank maintains system pressure via a custom-molded internal rubber bladder. The completely sealed tank never needs maintenance, and may be installed in the mechanical room, or even buried outside with the ground loop. Designed for up to 6 tons (approximately 3/4 gallon capacity).
This product solves the problem of pressure fluctuations in the ground loop system, and call-backs to re-pressurize the loop.