How to Know When It's Time to Replace Your HVAC System

PG&E
HVAC system

You're sitting at your desk, going through the mail, when suddenly your eyeballs bulge. There in front of you is your company's latest utility bill, and it has shot up again for the third month in a row, for no discernible reason. It's springtime in California; the outside temperatures have been pretty steady—cool, but not cold. Business has been good, but not crazy. What's up?


A number of factors could be to blame for higher utility bills, but chances are if your heating, ventilation and air conditioning (HVAC) system is getting on in years, it is the likely culprit. A commercial HVAC system that is aging or hasn't been properly maintained is operating inefficiently, costing your business money and wasting energy. It can also lead to health, comfort and productivity issues among employees and customers.


You can determine if your commercial HVAC system is to blame for your rising utility bills by monitoring them and comparing current gas and electricity use with prior use. Evaluate the way the HVAC system was used in the past and how it is used now. If there hasn't been any changes in the electricity or gas rate, usage patterns or weather conditions, higher bills probably mean the HVAC system is underperforming.


And higher utility bills are just one indication that it might be time to replace your commercial HVAC system with a modern, energy efficient model. Here are five other red flags to look for that will indicate your HVAC system may be due for a replacement:


1. Indoor spaces are not being heated or cooled properly

Aging heating and cooling systems might cycle on and off too frequently and employees may regularly complain about an uncomfortable work environment. If standard tune-ups and adjustments aren't resolving the issue, a commercial HVAC system replacement may be necessary.


2. Indoor air quality and airflow are not up to standard

Clean air and a balanced airflow are important to making a business as healthy and productive as possible. If your system is no longer getting the job done, it may be time to replace it. In addition, consider the benefits of ENERGY STAR-certified HVAC systems that are equipped with demand-controlled ventilation and enhanced ventilation control. These additional features can solve air quality and airflow problems.


3. The current HVAC system is approaching its expected lifespan

Knowing the age and repair history of your current HVAC system is critical to making repair decisions. The older the system, the more likely it is that replacement will be the best option. According to ASHRAE (formerly the American Society of Heating, Refrigerating and Air-Conditioning Engineers), furnaces and boilers usually need to be replaced at least once every 18 to 24 years. For air-conditioning units, 15 years is the suggested lifespan.1


4. Energy is being lost in the exhaust

Exhaust air from inefficient HVAC systems wastes a major opportunity for more efficient heating and cooling. That's because more energy is required to heat or cool incoming outside air. But newer ENERGY STAR-rated HVAC systems incorporate features that prevent HVAC energy waste. Heat-recovery technology transfers energy from exhaust air to incoming outside air. This greatly reduces the energy that's required to heat or cool incoming air. As a result, businesses can recover 50% to 80% of HVAC energy waste.2 A qualified contractor can show you HVAC systems featuring a variety of heat-recovery options, such as heat exchangers, recuperators, regenerators, passive air pre-heaters and waste heat boilers, which help achieve energy efficiency for California businesses.


5. Older, inefficient thermostats are still in use

You want your employees to be comfortable when they're at work — warm in the winter and cool in the summer. But what about temperature settings for late at night or when your business is closed? Keeping the office temperature constant when no one is around isn't necessary and contributes to HVAC energy waste. Modern HVAC systems employ programmable thermostats to monitor the building's heat or cooling output. Temperatures will automatically go up or down at preset times when no one is around. You can also program the thermostat so that the temperature is a little cooler during the winter months and warmer during summer. Generally speaking, people are comfortable at 78 degrees in the summer and 68 degrees in the winter.


If your HVAC system is exhibiting any of the signs above, it may be time to replace it. Your first step should be to find a qualified contractor to work with. Download "The Complete Guide to Working with a Lighting or HVAC Contractor" eBook from PG&E and go beyond the deliberation stage in an HVAC system replacement. Explore product and incentive options with a contractor to develop a long-term quality maintenance plan.


Referenced in article:

  1. ASHRAE (PDF)
  2. ENERGY STAR
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