Flow sensors can potentially be damaged by winterization blow-out techniques, and should be removed prior to injecting compressed air into the pipes.
Hunter Flow Sync and Flow-Clik sensors are installed in FCT tee fittings. The flow sensor itself includes an impeller, which rotates in the flow on a metal spindle. When compressed air is used to blow standing water out of pipes, the impeller spins much more rapidly than usual, and can be damaged.
The FCT fittings are supplied with a blank plug (P/N 536100) installed inside the adaptor. This is removed when the actual flow sensor is installed.
Save this blank plug! You can use it to temporarily replace the flow sensor during winterization blow out, to prevent damage to the sensor from high velocity air.
- Shut off the water supply
- Disconnect flow sensor wiring, and remove the wiring cover.
- Unscrew the threaded cap.
- Remove the flow sensor assembly.
- Insert the blank plug, and replace the threaded cap.
- Proceed with the compressed air blow out.
- Reinstall the flow sensor, cap and cover, and reconnect wiring with quality waterproof connections.
The flow sensor will then be ready for the next irrigation season.
Replacement plugs are available from Hunter Industries as P/N 536100.
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