The VT2218 comes with 2 temperature sensors to provide Delta-T readings to the pump's brain. So it's ready to slash fuel bills right out of the box. The VT2218 is whisper quiet and has a big, bright LCD screen that's easy on the eyes. Simple push-button navigation lets you set the pump to any one of five modes quickly and easily. But what you can't see is just as important: our innovative Bio Barrier protects the rotor and bearings from system contaminants. Delta-T is the comfort standard for American homes. With our infinitely variable speed ECM motor, the VT2218 uses up to 85% less electricity and maximizes total system and boiler performance. The bottom line more comfort for a lot less money. The VT2218 can slash fuel bills by hundreds of dollars. Its companion, the Zone Sentry zone valve, draws up to 93% less energy, uses fewer components and can handle up to 12 valves per standard 40 VA transformer. When it comes to zone valves, the Zone Sentry is the smartest decision you can make.