The 106-A-Type 3 and 206-A-Type 3 altitude control valves are based on the 106-PG or 206-PG main valve, and are ideal for maintaining preset maximum level.
The Type 3 allows normal forward flow to fill the reservoir to the maximum level, then closes drip-tight at the set-point. The valve opens to permit reverse flow through the valve when the supply pressure drops an adjustable amount below the reservoir head.
The Type 3 will then allow normal forward flow to refill the tank to the maximum level, when a higher supply pressure is restored.
For more information on the 106 / 206-A-Type 3 Flow Altitude Control Valvewith Differential Control: