Air Quality HVAC

Dealing with a Leaking Bathroom Fan: Causes and Solutions

Bathroom Vent Fan Dripping Water

Discovering water dripping from your bathroom fan, even after a shower, can be perplexing. If you’re unsure how to address this issue, fret not – we’ve consulted professionals to guide you on what to do when your bathroom fan is dripping water, especially during the winter months.

Causes of Bathroom Fan Dripping Water

The presence of a double dash error on your Mr. Cool air conditioner usually indicates a communication problem between the indoor and outdoor units. Several factors could contribute to this error:

1. Loose or damaged wiring connections
2. Faulty control board
3. Issues with the temperature sensor

When these components fail to communicate effectively, it can impact the overall performance of your air conditioner.

Troubleshooting Steps for Bathroom Fan Dripping Water

If your bathroom exhaust fan is dripping water, consider the following steps:

1. Inspect wiring connections: Check for loose or damaged wires between the indoor and outdoor units. Ensure secure and proper connections.

2. Reset the unit: Turn off the power supply, wait a few minutes, and restart it to see if the error persists.

3. Clean air filters: Regularly clean or replace air filters to maintain proper functionality and prevent communication issues.

4. Contact a professional: If the issue persists, seek assistance from a qualified HVAC technician to diagnose and fix the problem.

Preventing Future Errors

To avoid future occurrences of bathroom fan dripping water, follow these tips:

1. Schedule regular maintenance: Engage a professional HVAC technician for routine maintenance to identify and address potential issues proactively.

2. Maintain cleanliness: Ensure the outdoor unit is free from debris and obstructions to optimize performance.

3. Follow manufacturer’s guidelines: Refer to the user manual for maintenance and troubleshooting specific to your Mr. Cool air conditioner model.

Understanding Why a Bathroom Fan Drips Water

A bathroom fan is designed to remove moisture, preventing the growth of mold and mildew. However, water dripping from this device can be a concern. The potential reasons include:

1. Condensation in ducts: Occurs when warm bathroom air meets cool air, leading to condensation, especially in winter.

2. Water from the roof: Melting ice on the roof can enter bathroom ducts if not properly insulated.

3. Incorrect fan installation: Gaps due to improper installation can allow water seepage during rain.

How to Repair a Leaking Bathroom Fan

Once you’ve identified the cause, consider these solutions:

1. Duct insulation: Ensure proper insulation to control temperature and reduce condensation.

2. Check the damper: Inspect and replace a faulty damper that obstructs airflow.

3. Examine the vent cover: Assess for damage and consider repairs or replacement by a professional.

4. Reposition the fan: Place the fan away from the shower to minimize condensation.

5. Change the fan: If necessary, upgrade to a more effective fan.

6. Clean the fan: Regular cleaning prevents airflow obstruction.

Should You Leave the Bathroom Fan On?

Leaving the fan on during a shower expels warm, moist air, aiding ventilation. It’s advisable to keep it running for 10-15 minutes after bathing to ensure thorough moisture expulsion and prevent issues.


Understanding the causes and solutions for a leaking bathroom fan empowers you to address the issue effectively. Follow preventive measures, identify the specific problem, and consider professional assistance for a quick resolution. Regular maintenance and adherence to guidelines ensure optimal performance of your bathroom fan.


Do bathroom fans need maintenance?

Yes, bathroom fans need regular cleaning to ensure proper functionality and prevent issues like mold growth. Run the fan during and after showers to eliminate excess moisture.

How can I stop my bathroom exhaust duct from dripping condensation?

To reduce condensation in your bathroom exhaust duct, consider these steps:

1. Reduce humidity: Use a dehumidifier to lower humidity levels around the ducts.
2. Clean obstructed ducts: Regularly clean any ducts that might obstruct airflow.
3. Maintain air filters: Keep air filters clean and change them every three months.

By implementing these measures, you can minimize condensation and prevent water droplets from forming in your bathroom exhaust duct.

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About the author


I am Ben , a seasoned HVAC specialist with over 6 of experience in the HVAC industry. I holds HVAC Certification and has a proven track record in providing expert advice on HVAC systems.