HVAC Facts – Answers to Your Common Questions Part 2

A closeup of a commercial air conditioner on a roof

In Part 1 of this series, we dove into some of your common HVAC questions from ‘what is HVAC?’ and ‘what equipment requires preventative maintenance?’ (N.B. all of it does) to tips on what you can troubleshoot on your own and answers to all of your air filter FAQs. In the spirit of spring being upon us, here we’re going to focus on questions we often receive geared towards air conditioning equipment and overall indoor air quality for your commercial building.

While reviewing these great tips, keep in mind how vital preventative maintenance on your unit is to its overall operation and lifespan, not to mention how it helps eliminate costly unexpected repairs. Make sure to beat the heat by giving your professional HVAC technician a call to set up your appointment before your AC has to kick into high gear.

Air Conditioning Equipment

When should I replace my central air conditioner?

The average lifespan for an air conditioner in residential and light office applications is 15 years. Systems in commercial applications such as restaurants and bars, data rooms, or busy shopping centers can be less than this, as AC units are run much harder in these settings.

If your AC system is close to 10 years old, you should start thinking about replacement. Older systems aren’t as energy efficient as newer ones, which can result in higher operating costs.

When replacing the outdoor system, should the indoor unit also be replaced?

Yes. A properly matched system will have ideal efficiency and performance.

What could be the cause of the indoor coil freezing up?

A dirty coil/filter will cause a lack of airflow, which in turn will cause the AC to be starved of air and therefore freeze up. Another cause would be that your system is low on refrigerant due to a refrigerant leak. Central air conditioners are closed, sealed systems and do not require charging on a regular basis. If there is a leak, it should be repaired.

What is two-stage cooling?

Two-stage cooling means the air conditioner has a compressor with two levels of operation, which is like having two AC units in one. AC units are typically sized for the hottest days of the year, but the majority of the time you don’t need the full capacity of your AC.

What is inverter or variable speed cooling?

Inverter or variable speed cooling is basically modulated cooling. While two-stage cooling has only two stages, variable stage cooling will modulate according to the load demand, making the compressor only run as hard as it needs to for the highest level of efficiency possible.

What is the minimum energy efficiency standard for air conditioners in my state?

In our northern region of North Dakota and Minnesota, the minimum energy efficiency standard is 13 SEER for a split system AC and 14 SEER for single package air conditioners. Find the standards specific to your region here.

Indoor Air Quality

Can indoor air be hazardous to your health?

Absolutely! Exposure to air pollutants can be up to 100 times higher indoors than outdoors, and poor indoor air quality (IAQ) can be a direct or indirect cause of several health problems. Proper ventilation plays an important role in improving IAQ, helping to reduce the concentration of pollutants inside the home or building. Click here to learn more about how indoor air can affect your health.

Should I have my air ducts cleaned?

The National Air Duct Cleaners Association recommends cleaning your air ducts every 3 to 5 years.

Why is our office so humid?

Many things can affect humidity; dirty coils, for one, can reduce cooling and dehumidification. Another cause of high humidity is drawing in too much outside air in the summertime than your AC can handle. If the setpoints of the indoor air quality system are set correctly, there may be a malfunction in the system which needs to be checked by a trained professional.

Is too much humidity a bad thing?

If humidity is too high, it can cause discomfort and condensation on your windows, in addition to a bad hair day. If it’s too low, it can cause static electricity and respiratory problems.

What is the proper indoor humidity level?

Optimum humidity levels are between 35% – 50%, but in any case they should be kept between 30% and 70% depending on location and comfort level.

Your commercial building’s HVAC equipment provides your facility with comfort year-round. It’s no small feat to accomplish this; as a crucial component of your building, your HVAC system needs to be cared for by qualified experts to keep it running safely, optimally and for a long time to come. To schedule your spring maintenance appointment or ask one of our qualified experts a specific question, visit our website or give us a call at 701.775.0305.