AH9000 Mobile Delivery Unit Water Relay Test and Repair

The water relay is located inside the delivery system under the lid. The water relay stops the water flow to the needle valves until the foot control (throttle valve) is pressed, then air flows to the water relay and opens the needle valves allowing water to flow to the instruments. It also supplies water directly to the syringe.

Water Relay Testing

1.Disconnect power. Open lid. Refer to: Access Procedures

2.Disconnect orange tubing from water relay. Depress foot control.

3.Disconnect tubing from water relay manifold. Depress foot control.

Results	Status	Required Action
No water when foot control not depressed.		Water flow good.
Water when foot control is depressed.		Water flow good.
No air flow when orange tube is disconnected.		Tubing clogged or damaged. Change orange tubing.
No water flow when manifold tubing is disconnected.		Water relay is bad. Replace water relay.