Lennox Commercial

Frequently Asked Questions

Energy Efficiency

Why should I choose ENERGY STAR® qualified products?

Choosing commercial heating and cooling equipment that has earned the ENERGY STAR can save your business approximately $3 - $4 per square foot over the lifetime of the equipment*, according to the U.S. Department of Energy.

Lennox has developed a complete line of ENERGY STAR qualified products including packaged rooftop units, air conditioners, heat pumps, thermostats and furnaces.

*Facts developed by the Climate Change Action Plan and Lawrence Berkeley Laboratory research.

How can I reduce my building's energy costs?

According to the U.S. Department of Energy, as much as 50% of a commercial building's energy is used to operate its HVAC system*. Higher-efficiency systems and advanced technology from Lennox can help businesses reduce their operational spending by creating comfortable buildings that use less energy.

Compare lifecycle costs

Controlling operational costs is much more than choosing the lowest priced equipment. Installing a system with a lower lifecycle cost can help reduce energy and maintenance costs for the life of the system.

Look for systems with higher energy-efficiency ratings to reduce monthly energy bills. Adding efficiency options such as economizers can improve efficiency even more.

Another way to reduce costs is to choose systems that are easy to install – with features such as hinged access panels – to save labor hours. Reliability features including high- and low-pressure switches that protect compressors from unnecessary wear and tear minimize maintenance expenses.

Investigate new technologies

Demand Control Ventilation

Most HVAC systems provide ventilation based on assumed occupancy, rather than how many people are actually in the room at any given time. Installing a Demand Control Ventilation (DCV) system with a carbon dioxide sensor provides an accurate reading of a room's occupancy level. The system then controls the amount of fresh air introduced based on output from the CO2 sensor.

The result is improved energy-efficiency and indoor air quality.


When a building soaks up heat from equipment, lighting and occupants, the warmth may continue to heat the building even when the outside temperature is cool and comfortable.

That's when it is more economical to shut off the compressors and cool using outdoor air. Integral economizers measure outdoor air's temperature and humidity, determining if it is cool and dry enough to keep occupants comfortable. The economizer will then use the outside air for cooling rather than operating the compressors.

Building Automation Systems

Commercial control systems are available that use a single interface to control a variety of equipment and functions. These include sophisticated technologies such as remote monitoring, advanced diagnostics, system setup and alarm reset.

Equipment made by different companies can communicate with each other via BACnet® and LonTalk® protocols. BACnet or LonTalk capability can be installed on rooftop units to let them communicate with the automation system you use.

Investigate a planned replacement program

Most commercial rooftop HVAC systems have approximately a 15-year lifespan. Replacing a unit a few years earlier on a prearranged schedule—before age and wear take their toll—can dramatically reduce energy usage and help avoid lost revenue.

Installing newer, more energy-efficient equipment can reduce energy costs. While savings vary depending on system settings, maintenance, local fuel rates and other factors, today's ENERGY STAR qualified HVAC systems offer significantly higher SEER efficiency ratings.

According to the U.S. Environmental Protection Agency (EPA), the owner of a commercial building can generate $2 to $3 of incremental asset value for every $1 invested in energy performance improvements. Many utility companies also offer rebates for higher efficiency equipment.

*Office of Energy Efficiency and the U. S. Department of Energy

What is two-stage cooling?

Two-stage cooling means the air conditioner or heat pump has a compressor with two levels of operation: high for hot summer days and low for milder days. Since the low setting is adequate to meet household-cooling demands 80% of the time, a two-stage unit runs for longer periods and produces more even temperatures.

Longer cooling cycles also translate to quieter, more efficient operation and enhanced humidity control. Compared to a single-stage unit, a two-stage air conditioner or heat pump can remove twice as much moisture from the air. This is important because when moisture levels are high, there's a higher potential for mold and other pollutant problems.

What is two-stage heating?

Two-stage heating means the furnace has two levels of heat output: high for cold winter days and low for milder days. Since the low setting is adequate to meet cooling demands 80% of the time, a two-stage unit runs for longer periods and provides more even heat distribution.

Longer, low-capacity operation has many advantages:

Consistent comfort

Two-stage heating eliminates the temperature swings associated with standard furnaces, regulating temperature to within as little as one degree of the thermostat setting.

Quiet operation

Two-stage furnaces start in the first stage, when the amount of heat required is lower, instead of reaching full capacity all at once. That means there's no sudden "kick" or blast of air.

Improved air filtration

Low-speed operation allows your filters to capture more contaminants (because air is constantly passing through them), so you can breathe easier.

Efficient performance

Because the furnace operates mostly in its lower-capacity first stage, it burns less fuel than a standard furnace that always runs at full capacity and shuts off when the heating demand has been met.

Why should I zone my building?

A zoning system is designed for the many ways you use your building. Maybe you're caught up in coworker "thermostat wars." Or perhaps you have unoccupied areas that do not need conditioning. A Lennox® zoning system allows you to divide your business into separate areas, giving you the comfort and control you've always wanted.

The main benefits of commercial zoning are:


Zoning meets the specific temperature and airflow requirements of one area, without affecting other areas.


A properly designed zoning system can save you hundreds of dollars in energy costs each year.


Zoning divides a space into different areas and comfort into different levels, giving you more choices and control than ever before.

Quiet Performance

When integrated with variable speed and/or two-stage HVAC systems, zoning allows your heating and cooling equipment to deliver peak performance and efficiency without continually operating at peak capacity. Lower speeds mean lower sound levels.

What do all those air conditioner and heat pump ratings mean?

SEER (Seasonal Energy Efficiency Ratio) is a system for rating the efficiency of cooling equipment. The higher the SEER rating, the less your unit will cost to operate.

HSPF (Heating Seasonal Performance Factor) is a measurement similar to SEER, but it measures the efficiency of the heating portion of a heat pump.

Energy Efficiency Ratio (EER) This measures the cooling output of a unit divided by its total energy consumption, measured during continuous operation at a given operating condition (95 degrees or full load).

Integrated Energy Efficiency Ratio (IEER) This measure expresses cooling part-load EER efficiency for commercial unitary air conditioning and heat pump equipment on the basis of weighted operation at various load capacities.

© 2019 Lennox International Inc.