Wondering how to turn off Aprilaire humidifier without damaging your HVAC system or wasting water? If your whole-home humidifier is running when you no longer need it, knowing the right shutdown steps can help you avoid unnecessary moisture, maintenance issues, and higher utility bills.
How to Turn Off Aprilaire Humidifier
Turning off an Aprilaire humidifier is usually a simple process, but the exact steps can vary depending on the model and whether it is connected to your furnace or HVAC system. Most Aprilaire humidifiers are controlled through a humidistat, furnace switch, or dedicated power switch. Before you start, make sure you know which type of Aprilaire unit you have.
Step 1: Set the Humidistat to Off or the Lowest Setting
The first step in how to turn off Aprilaire humidifier is to check the humidistat. This control regulates indoor humidity levels.
If your model has a dial or digital humidistat, turn it to the OFF position if available. If there is no off option, set it to the lowest humidity level. This usually stops the humidifier from calling for moisture.
Step 2: Turn Off the Furnace or HVAC Power
Many Aprilaire humidifiers run only when the furnace blower is operating. To fully shut off the system, switch off the furnace power at the service switch or circuit breaker.
This is especially useful if you want to stop the humidifier for the season or perform cleaning and maintenance. Always make sure the HVAC system is off before touching any internal components.
Step 3: Shut Off the Water Supply
Most Aprilaire whole-house humidifiers use a water line connected to the unit. Locate the saddle valve or shutoff valve on the water line and turn it clockwise to stop the water flow.
Shutting off the water supply prevents dripping, leaks, and unnecessary water use. If you are turning off the humidifier for an extended period, this is an important step.
Step 4: Turn Off the Humidifier Power Source
Some Aprilaire models have a dedicated power switch or are wired through the furnace control board. If your unit has its own switch, turn it to the OFF position.
If there is no separate switch, disconnect power through the furnace or HVAC system. Do not attempt to remove wiring unless you are qualified to do so.
How to Turn Off Aprilaire Humidifier for Summer
In warmer months, you may want to shut down the humidifier completely since indoor air naturally holds more moisture. To turn off Aprilaire humidifier for summer use, follow these seasonal steps:
- Set the humidistat to OFF or the lowest setting.
- Turn off the water supply.
- Switch off the humidifier or furnace power if needed.
- Inspect the water panel or evaporator pad before storing the system in inactive mode.
This helps reduce mineral buildup and keeps the unit ready for the next heating season.
Should You Turn Off an Aprilaire Humidifier at the Furnace?
If your Aprilaire humidifier is wired to run only with the furnace, turning off the furnace often disables the humidifier too. However, some systems still allow water flow if the humidistat is calling for humidity.
For complete shutdown, it is best to turn off the humidistat, water supply, and power source when possible. That gives you better control and reduces the risk of unwanted operation.
When to Call a Professional
If you cannot find the humidistat, water shutoff, or power switch, check your Aprilaire manual for the model-specific instructions. If the unit is hardwired or you are unsure about the wiring, contact an HVAC technician.
A professional can safely turn off the humidifier, inspect the system, and make sure there are no leaks or electrical concerns.
Final Thoughts
Learning how to turn off Aprilaire humidifier is easy once you know the controls. In most cases, simply setting the humidistat to off, shutting off the water supply, and disconnecting power will do the job. Whether you are turning it off for summer, maintenance, or troubleshooting, these steps can help protect your HVAC system and keep your home comfortable year-round.
