The following illustration describes six possible ways to wire your Aprilaire humidifier to your furnace or air handler. The wiring diagrams necessary for your installation will vary depending on the equipment that you are installing your Aprilaire humidifier with. Please take note of the difference between the high and low voltage lines. You DO NOT want to connect high voltage lines directly to a low voltage unit such as the humidistat controller. This will damage your unit and void the warranty. It is recommended to test all installation wires with a voltmeter to determine each wire's voltage.

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How To Wire Your Aprilaire Humidistat