Bypass Humidity Sensor on Bathroom Fan (Steps Guide)

Bypass Humidity Sensor on Bathroom Fan

Bathroom fans are imperative for decreasing bathroom humidity levels and preventing moisture-related troubles such as mold and mildew. These fans are outfitted with humidity sensors that turn on automatically when the humidity levels rise above a positive point. However, some people decide to have manual control over their bathroom fan, and bypassing the humidity sensor is the way to do it. In this article, we’ll review the steps to bypass a bathroom fan’s humidity sensor.

Bypass Humidity Sensor on Bathroom Fan

How to Bypass the Humidification Sensor on a Bathroom Fan?

Bypassing the humidification sensor on a bathroom fan can be achieved without problems with the right tools and a fundamental understanding of electrical wiring. In this step-by-step guide, we’ll take you thru the process of bypassing the sensor so that you can manually control your bathroom fan’s operation.

Tools and Materials Needed: 

Before starting, it’s essential to have the right tools and materials. You’ll need a voltage tester, wire cutters, wire strippers, electrical tape, and a screwdriver. You’ll also need the fan’s wiring diagram, which you can find in the fan’s manual.

Step 1. Preparing for the Job

  • Please turn off the power: Before starting any electrical work, turn off the power supply to the bathroom fan by switching off the circuit breaker that controls it.
  • Remove the fan cover: Use a screwdriver to cast off the screws that keep the fan cover in place. Set the cover apart in a safe place.
  • Locate the humidity sensor: Look for the humidity sensor, typically set up on the aspect of the fan housing or the duct linked to the fan. 

Step 2. Bypassing the Humidity Sensor

  • Identify the wiring: Locate the wiring that connects the humidity sensor to the fan motor. The wiring might also be color-coded. However, if not, use a voltage tester to determine which wires are hot and which are neutral.
  • Disconnect the wiring: Once you have identified the wiring, disconnect it from the humidity sensor. You might also want to use wire cutters or a wire stripper to remove any insulation covering the wires.
  • Connect the wiring for guide control: Connect the wires previously connected to the humidity sensor to the guide control switch. Follow the manufacturer’s directions for wiring the switch and connecting the hot and impartial wires to the fantastic terminals. 

Step 3. Testing the Fan

  • Turn on the power: Once you’ve wired the manual control switch, turn the power back on by switching the circuit breaker back on.
  • Turn on the fan: Flip the manual control switch to the “on” position to turn on the fan. The fan should now run continuously, regardless of the humidity level in the bathroom.
  • Check the fan’s operation: Test the fan by running it for a few minutes and checking that it works properly. If the fan does not turn on, turn off the power and double-check your wiring.

 Step 4. Replacing the Fan Cover

  • Secure the cover: Once you’re satisfied that the fan is working properly, reattach the fan cover using the screws you removed earlier.
  • Turn the power back on: Finally, turn the power back on at the circuit breaker to restore power to the bathroom fan.

Congratulations! You have successfully bypassed the humidity sensor on your bathroom fan and can now control it manually. Remember to exercise caution when working with electricity and always turn off the power before modifying your electrical system.

Frequently Asked Questions and Answers

How do I lower the humidity in my bathroom without a fan?

If you don’t want an exhaust fan put into your bathroom, installing a fresh air intake vent can be an excellent alternative – and they often give better results. A new air intake will improve air circulation, control humidity, and channel fresh, natural ventilation from the outside air.

Is it safe to bypass the humidity sensor on a bathroom fan?

Bypassing the humidity sensor on a bathroom fan may not be safe or recommended, as the sensor is designed to ensure proper ventilation and prevent the growth of mold and mildew. If the sensor is malfunctioning, replace it or repair it rather than bypass it. Additionally, bypassing the sensor may void the warranty on the fan and could lead to other safety issues if not done properly.


Bypassing a humidity sensor on a bathroom fan is a noticeably simple process requiring only a few tools and fundamental electrical knowledge. However, it is essential to follow the steps cautiously and ensure the power is off before starting. With some care and attention, you can manipulate your bathroom fan and keep your toilet humidity-free. Remember, if you are no longer comfortable working with electricity, it is constantly exceptional to consult a professional. 

Leave a Comment

Your email address will not be published. Required fields are marked *