Furnaces are rated by the Annual Fuel Utilization Efficiency (AFUE) ratio, which is the percent of heat produced for every dollar of fuel consumed.
Like the miles-per-gallon rating on your automobile, the higher the AFUE rating, the lower your fuel costs. All furnaces manufactured today must meet at least 78% AFUE. If your furnace is 10-15 years old, it very well may fall below the current furnace minimum and waste energy.
This doesn't mean that you should only select a furnace based on its AFUE rating. The efficiency rating is just one factor to consider when looking for a new furnace.
Furnaces use electricity to run fans and motors. The amount of electricity used varies greatly depending on the type of furnace. Be sure to check electricity usage prior to making a purchase decision.
The term "variable speed" refers to the furnace's indoor blower motor, which moves at different speeds to precisely control the flow of heated and cooled air. Better airflow control has several benefits:
Variable speed motors can actually save you money on your energy bills, as they consume less electricity than standard motors.
Variable speed technology also means you will gain heating efficiency or AFUE.
Variable speed motors are excellent for zoning, which allows you to customize your comfort in different areas and control your energy bills.
A variable speed motor can also help clean the air. When the fan is in constant operation (indicated by the "Fan" setting on your thermostat), the motor will continue to slowly circulate air, allowing filters to capture more contaminants.
A heat pump is an all-in-one heating and air conditioning system that works year-round to keep you comfortable.
During warmer months, a heat pump works as a normal air conditioner. It extracts heat from inside and transfers it to the outdoor air. In colder weather, however, the process reverses—the unit collects heat from the outdoor air and transfers it inside.
Even when the air outside feels extremely cold, the air still contains some heat. The heat pump pulls the heat from this cold outdoor air and sends it inside to warm the space. When there's not enough heat in the outside air to meet the demand of the thermostat setting, an electric heater supplements the outdoor air to warm the space. Extremely efficient, this process produces two to three times more heat than the energy it uses.
Also, a heat pump can be an effective add-on option to use in conjunction with an existing gas furnace. With this dual-fuel option, the two systems share the heating load, but never function at the same time. Each system operates when it is most cost effective. The heat pump will be the primary heating and cooling system. However, when the temperature drops below the heat pump's ability to operate as efficiently as the gas furnace, the gas furnace will take over until the temperature rises enough for the heat pump to operate more efficiently.
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:
Two-stage heating eliminates the temperature swings associated with standard furnaces, regulating temperature to within as little as one degree of the thermostat setting.
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.
Low-speed operation allows your filters to capture more contaminants (because air is constantly passing through them), so you can breathe easier.
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.
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.
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.