Profile: Advantay Ltd. specializes in the domestic and industrial heating ventilation and air conditioning markets. We are an ISO 9001:2000 certified company. Our product line includes pressure relief (safety) valves, automatic air release valves, manual air vents, differential bypass, pressure reducing, motorized, blending, fan coil, radiator, and full bore ball valves. We provide pressure (safety) relief valves for use in water heating equipment. Each valve is pre set and not adjustable. It is designed to release excess pressure. Manual air release valves are designed for use within heating system to allow safe manual release of air trapped in the system.