Understand the “Feels Like” Temperature in Your Facility
The temperature your thermostat displays and the temperature your body feels aren’t always the same. The apparent temperature, or “feels like” temperature, in your facility depends not only on the air temperature, but also on the indoor humidity and airflow. Both can be a problem in the Delaware and Pennsylvania area’s humid summers and cold winters.
If your thermostat suggests your building should be comfortable, yet your staff and customers complain about the temperature, don’t be too quick to blame the furnace or air conditioner.
The Effect of Humidity
The amount of moisture in the air affects the “feels like” temperature, regardless of the actual thermostat temperature. The ideal indoor humidity level is somewhere between 40 and 60 percent. This depends on the outdoor temperature, so the most comfortable humidity level is lower in winter and higher in summer.
Winter air’s naturally low humidity combined with the drying effect of forced-air heating indoors causes low indoor humidity. Dry indoor air saps moisture from anywhere it can, including your skin. This creates an evaporative cooling effect that makes you feel chilly. It also leads to dry skin, chapped lips, and itchy eyes.
If your building’s indoor humidity falls below 35 percent in winter, you may need a humidifier. An in-duct humidifier sits inside your HVAC system and adds moisture to the air passing through. The humidified air is then distributed through the ducts to all parts of the building.
In summer, excess humidity is the more common problem. Damp air reduces your body’s ability to cool itself by sweating, increasing the “feels like” temperature and leaving you feeling hot and sticky. An in-duct dehumidifier can solve this problem. This device removes excess moisture from the air passing through your HVAC system and drains the resulting water away through the plumbing system.
In a poorly ventilated building, excess humidity can occur in winter, too. In this case, you’ll benefit from upgrading your ventilation system before considering a dehumidifier.
The Effect of Airflow
Just like a brisk breeze can make a sunny day feel chilly, uncontrolled drafts in your building can reduce the “feels like” temperature. Air leaks are the most common source of drafts. Older buildings were often constructed with cracks and gaps around windows, doors, and other areas to provide a healthy amount of airflow. The problem with this ventilation method is that in addition to causing drafts, it wastes your conditioned air, creates humidity problems, and lets in outdoor air pollutants.
If your facility feels drafty, consult a heating and cooling specialist about performing an energy audit. A specialist will use equipment to pinpoint the leaks so they can be sealed with caulk and weatherstripping.
A forced-air heating and cooling system can also create drafts. If the problem is limited to just a few registers, try placing deflectors over these registers to redirect the airflow. If most of your air registers are creating drafts, the problem is likely to be the heating and cooling system itself.
The oldest furnace motors are single-speed. They can run only at full speed, pushing out large amounts of air, which causes drafts. Newer systems use two-speed or variable-speed motors. These run at lower speeds when you need less conditioned air, which is around 80 percent of the time in most buildings. These motors reduce drafts, minimize hot and cold spots, and save energy. If your HVAC system is more than 10 years old, consider upgrading.
Our goal is to help educate our customers about Plumbing, HVACR, Fire Protection, and Alarm Systems in Mechanical, Commercial, and Residential settings. For more information about managing your indoor “feels like” temperature and to view projects we’ve worked on, visit our website!
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