WOODWARD Low Pressure Regulator (LPR) Natural Gas/LP (Garretson/Impco KN Style)

Description

The N-LPR (Garretson/IMPCO KN Replacement) is designed for sensitivity and simple operation. It is used with low pressure gaseous fuels, where dependable starting is required. Because of its extreme sensitivity, the N-LPR offers excellent results in most remote starting applications (standby power generators, etc.) if installed and maintained properly. The item number 5233-1020 has a larger internal orifice and is suitable for LP engines up to 50 HP (37 kW) and NG engines up to 37.5 HP (28 kW).
The N-LPR is an automatic zero regulator. The engine creates a vacuum which acts through the outlet of the N-LPR on the diaphragm. Atmospheric pressure then forces the diaphragm toward the vacuum, depressing the lever and pulling the valve seat away from the orifice which allows fuel to flow as long as the demand persists. When the vacuum ceases, a spring force pushes on the lever and forces the seat valve against the orifice to theoretically shut off the fuel flow. It is important to remember that the Nat’l Fire Protection Assoc (NFPA) requires a separate fuel shutoff device be installed between the fuel source (LPG tank/Nat’l Gas Supply source) and the LPR regulator to ensure that fuel does not flow to the LPR inlet port when the engine is not running.
A properly adjusted N-LPR requires a vacuum of less than 0.35 inH2O (0.872 mbar) to start the opening sequence. Due to this sensitivity, most installations do not need priming to start unless low cranking speed or restricted and lengthy piping are required. This part number LPR does have a primer button.