Hi Cap. Engine Cooling Water Flow Detector - 3" Male NPT, for 3-1/2" Hose

This device activates a boat alarm (not included) upon loss of raw cooling water flow to the engine.
3.5" OD, designed for use on engines with 3-1/2" or 4" ID raw water hoses.

Made of PVC and designed for marine applications, it uses a 2-wire, non-polarity switch that is normally closed (normally open models are available).
Upon engine start, the switch opens when the coolant water flows, and the alarm shuts off at that point, and remains off as long as the flow of water exceeds the minimum flow rate.

While heat exchanger cooled engines will run several minutes without raw water flow before overheating, during that time significant damage can be done to the engine, raw water pump and exhaust system.
Monitoring raw water flow is a prudent step toward the safe operation of your engine.

• Monitors the flow of raw cooling water to engines, generators, or bait tanks
• Prevents costly engine damage when raw water intake is blocked by debris in the water
• Utilizes Aqualarm's latest Paddle Detector Technology that resists debris build-up
• Upgraded 3 amp electrical switch for alarm (versus 0.5 amps on old style detectors) Note - Instruction Sheet has not been updated yet
• Sets off alarm when flow rate falls below minimum
• Can be used with bell alarm (AQA#20100) or buzzer alarms (AQA#20106), etc.
• Multi-voltage - works with 12, 24, and 32 volt systems
• Typically plumbed by inserting the detector in between sections of coolant hose with double hose clamps at each end