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pressure regulator[′presh·ər ′reg·yə‚lād·ər]
Open-close device used on the vent of a closed, gas-pressured system to maintain the system pressure within a specified range.
1. In a fire sprinkler system, a device that limits water pressure, under both flow and no-flow conditions, in those portions of the system where it is probable that the pressure may exceed 175 pounds per square inch (11,400 kPa).
2. A pressure-reducing valve.
A device that reduces the pressure of the fluid from a high value to a lower value and, thereafter, maintains a constant output. The out pressure of the regulator can be adjusted. This is achieved by bypassing a portion of the fluid back to the inlet side of the pump.