Maybe you learned about it in Earth Science class, back in the day: air conditioners can reduce humidity. They do this by pulling warm air in and cycling it over cold coils. It produces condensation, removing moisture and reducing humidity in the air. 

Now you’re an adult, living in the real world. There’s more to the story than what you learned in Earth Science.

Here’s the rub: it is still common for air conditioners to measure temperature but NOT humidity.

Can you guess why this is problematic?

Here’s the answer: the air conditioner stops running when the ideal temperature is reached, NOT when the ideal relative humidity is reached. 

Therefore, a comfortable humidity level (for example, 55%) may never be reached!

What’s the solution? It’s multi-pronged.

1. A humidistat, which measures humidity, must be incorporated into the HVAC controller. What can be measured can be controlled.
2. Driving down the humidity level may make the room uncomfortably cold. Do it when no one is there.
3. Use correctly calibrated occupancy sensing. Some HVAC controllers come equipped with PIR (passive infrared) occupancy sensors.
4. Optionally, use an energy management system. It monitors humidity  levels, ensuring RH% is where you want it without compromising occupant comfort.

For the Techies

For the techies in the crowd (like us), here’s how it works:

This is all happening when no one is in the room. The HVAC system activates dehumidification cycles. It drives relative humidity to a defined level (for example, 55%). The sustained cooling-drives effectively dehumidify the air. 

Yes, relative humidity climbs in between refresh drives. But it never reaches the peak levels seen during the occupied period. 

The dehumidification cycle forces the HVAC system into a sustained cooling drive, which typically lasts for 10 to 15 minutes every 4 to 6 hours.

Fan coils with the heating coils in the re-heat position can be controlled to actively dehumidify: it reheats the air coming off the cooling coil, so over-cooling does not happen.

Bottom Line

It’s easier to dehumidify a room or living space that is unoccupied than one that is occupied. Without occupants in the space, the air conditioner can run more aggressively until the humidity in the air reaches a defined level. It does not disturb anyone with an uncomfortably chilly space, or the noise of a continuously running HVAC.

Download our white paper, “Effects of Humidity on Your Property”.

All this (and more) is possible today. Contact a Telkonet representative, and begin actively controlling your humidity levels while keeping everyone comfortable.

[email protected] or 888-703-9398