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#1 Reason to Choose 'Auto' Setting for Your Thermostat During the Day

by Megan Althoff | May 16, 2017 | Property Manager, property management maintenance, HVAC, Facility Manager | 0 Comments

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When it comes to correctly setting the thermostat of your multi-tenant residential property in Chicago, you may find yourself torn between setting the air conditioner fan to “on” or “auto”. The setting you choose should be based on your indoor air conditions. If you want more air circulation, you may want to turn the thermostat to “on” for a short while, but if you have a lot of humidity in your indoor air, you want to avoid the “on” setting.

Air Conditioner Fan On or Auto?

The “on” and “auto” settings only control your air conditioner’s fan. They do not control when your HVAC system is actually heating or cooling your air. The latter function is activated by your indoor temperature setting.

  • Running HVAC Fan Continuously – The “on” setting runs your HVAC’s fan continuously, regardless of whether your unit is heating or cooling the air. This can increase your utility bills, wear out your fan and motor and push humidity through your building.
  • Running HVAC Fan Only with Compressor – The “auto” setting only runs the fan when the unit is actively heating or cooling the air. This setting can save you money and ensures that the humidity is removed from your indoor air.

The Number 1 Benefit of Using the “Auto” Setting

Using the auto setting instead of running your HVAC fan continuously helps control humidity. Fans, by themselves, only move air around. When your air conditioners fan is operating without the benefit of the HVAC system’s climate control features, all the air does is move through the air ducts. If those ducts are located in basements, crawlspaces, attics or exterior walls, the air inside those air ducts could be hot and humid. This means that when the fan is turned to the “on” setting, that hot, humid air is simply pushed into the public areas of your multi-story residential building, which can make your residents uncomfortable.

When you choose the “auto” setting on your HVAC system’s thermostat, the fan operates when the air conditioner is cooling the air. This means that the air inside your building is pulled through the air filter and cooled while excess humidity is removed, which helps keep your indoor air cool and comfortable for all your residents.

Signs of Excess Humidity

If you choose to run your HVAC fan continuously, you should only do it for a short while in order to circulate the air in your building and alleviate any excessively stuffy rooms. Leaving the thermostat set in the “on” position for an extended period of time can lead to excessive humidity levels.

  • Condensation – If your building has excess humidity, you will notice condensation build-up on cold surfaces, like pipes, windows and bathroom fixtures, like the toilet tanks.
  • Mold and Mildew – Excess humidity can lead to the build-up of mold and mildew, which usually appears in bathrooms and kitchens first, but it can grow inside walls and along wooden window frames.
  • Indoor Allergy Symptoms – Excess humidity and an increase and mold and mildew can lead to worsening indoor allergy symptoms, breathing problems and headaches.

Optimizing Your Air Conditioner with Help from Althoff

If you are worried about the excess humidity, mold and mildew and air quality inside your multi-unit residential building in Chicago, our HVAC technicians can help you determine ways to improve your indoor air quality while optimizing the performance of your commercial air conditioner and helping you save money. We do this through our HVAC maintenance and inspection services and by informing you of ways to retrofit your HVAC system to make it more energy-efficient.

To learn more about thermostat settings or to schedule a service call for your HVAC system this summer, call us at 800-225-2443.

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