High Efficiency Furnaces

When considering a new gas furnace for your home, we recommend taking a look at the numerous benefits Rheem high efficiency furnaces offer.  These furnaces were built on the premise of providing savings, comfort and peace of mind. 

What makes a Rheem high efficiency furnace unique?

Unlike a standard furnace containing one heat exchanger, high efficiency furnaces contain two.  Having two heat exchangers allows the furnace to utilize more heat from the combusted gas, which means less money wasted through the chimney.  The primary heat exchanger of a Rheem furnace is constructed of aluminized steel, with the secondary being made of stainless steel.  This helps insure a long life of providing comfort.Rheem High Efficiency FurnaceRheem furnaces feature Direct Spark Ignition (DSI).  These are the only furnaces in the industry to utilize direct spark to ignite the flames of the furnace.  Other furnace manufacturers use Hot Surface Ignition (HSI).  HSI is an ignition system that is prone to crack and must be replaced every few years.  DSI, on the other hand, offers reliable flame ignition year after year for the life of the system.All Rheem furnaces have safety features including pressure switches, flame rollout switches, high temperature limit and flame sensing capabilities.Rheem furnaces come with a 5 year warranty on parts, and when registered, will be extended to a 10 year warranty.  There is also a lifetime warranty on the heat exchanger.Regarding your chimney, your new high efficiency furnace doesn’t need it.  Instead the combusted gas is exhausted through a PVC pipe that exits the side of your home.  If your water heater still uses the chimney, it is a wise investment to have a chimney liner installed to help protect your chimney. 

Multi Stage Operation

High efficiency furnaces come with the choice of having modulating, two stage or single stage operation.  For most of the heating season here in the DuPage/Cook county area our furnaces do not need to be using 100% of their capacity in order to properly heat our homes.  This is where multi stage furnaces show a true benefit.  By not using 100% of the furnaces capacity, comfort is still achieved and real money is saved. 


A modulating furnace means that the furnace is able to deliver exactly the amount of heat needed at any time of operation.  Coupled with a modulating thermostat, this furnace is able to produce heat at 40% through 100% of its capacity.  On its own, this furnace acts as a three stage furnace, firing at 40%, 65% and 100%.  This furnace is capable of perfectly maintaining even temperature at a greatly reduced operating cost. 

Two Stage

A two stage furnace will operate at 70% (First Stage) of its capacity for a determined amount of time, and if needed, will then move to 100% (Second Stage) of its capacity.  For a majority of our heating season this furnace will be operating in its first stage which will be using much less gas than your existing furnace. 

Single Stage

A single stage furnace will run at 100% of its capacity whenever there is a call for heat. 

Experience increased savings and comfort by getting a furnace featuring a variable speed blower.

A variable speed blower motor is a motor that is able to regulate the speed in which it spins to deliver optimal comfort, air flow and efficiency.  Unlike a regular blower motor that starts at full speed and stops immediately, a variable speed blower slowly ramps up to its desired speed and then slowly ramps down to create a more even air flow though your house, reducing drafts.  A variable speed motor can average 20% electrical saving compared to a standard blower motor.  If you typically keep your furnace fan on to continually move air throughout your home than variable speed is the right option for you.  

Annual Fuel Utilization Efficiency

The AFUE of a furnace, boiler, or hot water heater represents an average annual energy efficiency for that piece of equipment.  Shown as a percentage, furnaces for example, are available from 96% efficiency all the way down to 80% efficient.  A higher AFUE means more savings over the life of the unit and less energy wasted. 

Energy Star

A program created by the Environmental Protection Agency which certifies high efficiency products that save the consumer money and lowers energy usage.  According to the EPA requirements, the Energy Star label on efficient products have been third party tested.