Hatco S-6 Booster Heater - 3Ph, 208VAll models include a Castone lined tank with a 10 year limited warranty Features include a temperature pressure relief valve, a pressure reducing valve, two temperature pressure gauges, a high temperature limit control, pilot indicator light, On Off switch and a low water cut off to prevent element burnout due to a low water condition Each booster has a built in heat trap and fiberglass insulation to minimize heat loss Hatco Electric Booster Heaters