FEATURES & BENEFITS
Automatic tank fill and shut-off without the use of floats or sensors
Accurate shut-off to within inches of set point
High level point adjustable with single screw
Exhaust-to-atmosphere operation allows minimum pressure loss
Can be maintained without removal the line
Adjustable response speed
Factory tested and can be pre-set to your requirements
The model 3331 is designed for tank fill only, with discharge the tank by a separate line or by-pass. Tank head (pressure) is sensed
under the diaphragm of the altitude pilot. When tank head falls below the set point (spring set-ting), the pilot shifts to vent water the diaphragm chamber of the main valve. This allows the valve to open and fill the tank. When the tank level reaches the set point, the altitude pilot shifts to apply full inlet pressure to the diaphragm of the main valve, forcing the valve fully closed.
On 8" and smaller valves, the altitude pilot operates the main valve directly. On 10" and larger valves, the altitude pilot operates the main valve through a high-capacity three-way auxiliary pilot for more positive response.
The Model 3331 consists of the following com- ponents, arranged as shown on the schematic diagram:
1.) Model 65 Basic Control Valve
2.) Model 3300 Altitude Pilot
3.) Model 141-2 Needle Valve
4.) Model 159 Y-strainer Protects pilot system dirt/debris
5.) Model 141-4 Isolation Ball Valves
6.) Model 155 Visual Indicator
While most Model 3331 Altitude Valves are line size, definitive sizing information can be found in the OCV Catalog, Series 3330 section and Engineering section
Performance Charts. Consult the facto- ry for assistance and a copy of the OCV ValveMaster Sizing program.
(The pressures listed here are maximum pressures at 100°F.)
The altitude valve shall function to control the level in the tank without the use of floats or probes in the tank itself. It shall be a one-way flow (single-acting) type, designed to open fully to fill the tank and close completely when the predetermined high level is reached. Sensing of the altitude pilot shall be by means of a field-installed sense line between the pilot and the base of the tank. The altitude valve shall be equipped with a visual indicator assembly.