Rehlko

FF

UnclassifiedCooling

What This Code Means

Nuisance tripping of the Low Water Temperature (LWT) switch warning light / controller LWT lamp when the engine block is warm and the block heater is functional

Possible Causes

  • •LWT switch is located above the block heater thermostat and does not provide sufficient heat to keep the controller LWT lamp off

Suggested Actions

  1. 1Relocate the LWT switch using a 1/2 in. NPT black iron pipe tee (Part No. X-203-13), 1/2 in. NPT pipe plug (Part No. X-75-3), and 450 mm (18 in.) plastic conduit
  2. 2Disable generator set prior to service: move master switch to OFF, disconnect power to battery charger, and disconnect negative (-) battery cable first

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