WARNING: USE OF THIS DEVICE ON ANY LIFE SUPPORT EQUIPMENT IS EXTREMELY DANGEROUS AND COULD CAUSE INJURY OR DEATH WITHOUT WARNING.
WARNING: The OV2 valve must have a constant supply pressure to maintain a constant mass flow output. Use of a pressure compensating supply gas valve will cause changes in output flow rate.
The OV2 is an oxygen compatible control valve that uses an orifice to control flow and has a manual injection add button. The valve can be purchased with one of three different flow orifices and several different porting options. A 50 Micron filter screen is installed inside the inlet ports. All orifices also have a filter. Available orifice diameters are .0025, .003, or .0035 inch. Maximum allowable inlet pressure is 175 psig. The OV2 valve is the same as the OV1 valve except there is an additional inlet port for offboard hookup.
The OV2-2 valve shown above has standard scuba 9/16-18 male thread fittings in both onboard ports. The offboard inlet port comes with a standard 3/8-24 adapter installed and sealed with a standard 1/2 port plug.
The OV2-2 with a .003 flow orifice is part number OV2-2-003. The OV2-2-003 is often used on ECCRs as a safety backup and to reduce electronic injection requirements. Many MCCR divers use this valve to reduce manual injection requirements. The flow rate of the OV2-2-003 with an inlet pressure of 160 psig is approximately (.024 CFM or .67 LPM).
A 300 psig rated over pressure relief valve should be installed on the supply gas valve to help to prevent over pressurizing the OV2 valve. Over pressurizing of the valve can cause excessive flow or failure.
An inline shutoff valve should be installed between the supply gas valve and the OV2 valve.