ABSTRACT
Air separators free the air entrained in the water in a hydronic system. There are several types of air separators. The centrifugal type of air separator works on the action of centrifugal force and low velocity separation. Annular flow meters have a multi-ported flow sensor installed in the water pipe. The holes in the sensor are spaced to represent equal annular areas of the pipe in the same manner as the Pitot tube traverse is for round duct. Automatic temperature control valves are used to control flow rate or to mix or divert water streams. Calibrated balancing valves are designed to do both duties of a flow meter and a balancing valve. These valves are similar to ordinary balancing valves except the manufacturer has provided pressure taps in the inlet and outlet and has calibrated the device by measuring the resistance at various valve positions against known flow quantities.
