Products
Understanding Furnace Technology
Efficiency
90% Plus Furnaces
A 90% plus furnace has two heat exchangers (a primary and a secondary) and are commonly called “condensing” furnaces. These furnaces are capable of extracting at least 92% of the heat from combustion and transferring it into your home. The term “90% plus” means just that, the furnaces’s efficiency rating is above 90%. For each $1.00 of natural gas that the furnace uses, at least 92% (or $.92) is used to actually heat your home and the remaining 8% (or $.08) is vented to the outside through the sidewall or roof of your home using a PVC plastic pipe. All Carrier 90% Plus furnaces are “sealed combustion” and use outside air for combustion, which means that none of the air inside your home that you paid to heat is used to support the burner flame, thus saving more energy.
80% Efficiency Furnaces
An 80% efficiency furnace has only one (or primary) heat exchanger and extracts at least 80% of the energy from the combustion process and transferring it into your home. Simply stated, for each $1.00 of natural gas or propane that is used by the furnace, at least 80% (or $.80) is actually used to heat your home. The remaining 20% (or $.20) is vented out through your chimney or flue pipe. All 80% furnaces connect to your existing chimney or flue pipe.
Gas Valve Technology
Single-Stage
Single-stage gas furnaces are available in both 80% and 90% efficiencies. The term “single-stage” means simply that the furnace’s burners fire at one fixed heating level. When the thermostat tells the furnace to heat, the gas valve opens and the burner flame ignites. When the thermostat is satisfied, the burners shut-off.
Two-Stage
Like single-stage, two-stage gas furnaces are available in both 80% and 90% efficiencies. However, two-stage furnaces use a microprocessor along with a two-stage gas valve to control the burners at a high or low rate, depending on the heat demand. When the outside temperatures are moderate, the burners operate at a lower, more efficient rate. If the outside temperatures are very cold, then the furnace will operate at the higher rate in order to keep up with the heating demand. Some models change stages based on a fixed period of time, while others use a computer program to “analyze” the previous run times and adjust accordingly. This is the method Carrier uses and calls it “adaptive technology”.
Modulating
Modulating gas furnaces are very high efficiency furnaces, usually 95% and higher. These models also use computer technology along with special gas valves to control the burner output. The burner levels on these models operate at varying levels hence the term “modulating”. When the room thermostat calls for heat, the furnace fires and starts operating at a “medium” level. The furnace operates at this level for a short period and as the temperature gets closer to the set point, the furnace “modulates” to the lowest level until the thermostat is satisfied. In cases where the thermostat is set significantly higher than the room temperature or the heat demand is high, the furnace will operate on the highest stage in order to warm the home up as fast as possible.
Blower Motor Types
Standard Blower Motors vs. Variable-Speed
Today’s furnaces are available with standard or variable-speed blower motors. Most fixed-capacity furnaces today with standard blower motors will consume about 625 watts of electricity under normal operating conditions. Variable-speed blower motors operated in the continuous fan mode will use less electricity than a 100-watt light bulb. A typical variable-speed furnace with air conditioning will save approximately $350 to $400 per year in electricity costs. Additionally, variable-speed motors are much quieter than conventional motors and improve air circulation which results in reduced temperature swings and greater indoor comfort.
Furnace Selection
INFINITY® 98
Modulating Gas Furnace
59MN7
Features & Benefits
- Up to 98.5% AFUE heating efficiency
- Greenspeed intelligence for ideal comfort and energy savings
- Fully modulating gas valve capable of matching the heating needs of the home
- Variable-speed, ECM blower motor for ultimate comfort and ultra-quiet operation
- Ideal Humidity System® and SmartEvap™ technology to aid in summer dehumification
- ComfortFan™ technology allows fan-speed choices in “Constant ON” mode
- Comfort Heat Technology® feature intelligently stages heating cycles to reduce temperature swings and improve efficiency
- Infinity intelligence enables self-configuration and easy troubleshooting with Infinity control
- 10-year parts limited warranty
- Lifetime heat exchanger limited warranty
INFINITY® 96
Two-Stage Gas Furnace
59TN6
Features & Benefits
- Up to 96.7% AFUE heating efficiency
- Two-stages of heat for economical operation
- Variable-speed, ECM blower motor for ultimate comfort and ultra-quiet operation
- Ideal Humidity System® and SmartEvap™ technology to aid in summer dehumification
- ComfortFan™ technology allows fan-speed choices in “Constant ON” mode
- Comfort Heat Technology® feature intelligently stages heating cycles to reduce temperature swings and improve efficiency
- Infinity intelligence enables self-configuration and easy troubleshooting with Infinity control
- 10-year parts limited warranty
- Lifetime heat exchanger limited warranty
PERFORMANCE™ 96
Two-Stage Gas Furnace
59TP5
Features & Benefits
- Up to 96.7% AFUE heating efficiency
- Two-stages of heat for economical operation
- Multi-speed, high-efficiency, ECM blower motor enhances comfort
- Ideal Humidity System® and SmartEvap™ technology to aid in summer dehumification
- ComfortFan™ technology allows fan-speed choices in “Constant ON” mode
- Comfort Heat Technology® feature intelligently stages heating cycles to reduce temperature swings and improve efficiency
- 10-year parts limited warranty
- Lifetime heat exchanger limited warranty
PERFORMANCE™ BOOST 90
Single-Stage Gas Furnace
59SP5
Features & Benefits
- Up to 96.5% AFUE heating efficiency
- Single-stage operation
- Multi-speed, high-efficiency, ECM blower motor enhances comfort
- Ideal Humidity System® and SmartEvap™ technology to aid in summer dehumification
- ComfortFan™ technology allows fan-speed choices in “Constant ON” mode
- Comfort Heat Technology® feature intelligently stages heating cycles to reduce temperature swings and improve efficiency
- 10-year parts limited warranty
- Lifetime heat exchanger limited warranty
COMFORT® 95
Single-Stage Gas Furnace
59SC5
Features & Benefits
- Up to 95.5% AFUE heating efficiency
- Single-stage operation
- Fixed-speed blower motor
- ComfortFan technology allows fan-speed choices in “CONSTANT ON” mode
- 10-year parts limited warranty
- Lifetime heat exchanger limited warranty
COMFORT® 92
Single-Stage Gas Furnace
59SC2
Features & Benefits
- Up to 92.1% AFUE heating efficiency
- Single-stage operation
- Fixed-speed blower motor
- ComfortFan technology allows fan-speed choices in “CONSTANT ON” mode
- 10-year parts limited warranty
- 20-year heat exchanger limited warranty
INFINITY® 80
Two-Stage Gas Furnace
58CVA
Features & Benefits
- Up to 80% AFUE heating efficiency
- Two-stages of heat for economical operation
- Variable-speed, ECM blower motor for ultimate comfort and ultra-quiet operation
- Ideal Humidity System® and SmartEvap™ technology to aid in summer dehumification
- ComfortFan™ technology allows fan-speed choices in “Constant ON” mode
- Comfort Heat Technology® feature intelligently stages heating cycles to reduce temperature swings and improve efficiency
- Infinity intelligence enables self-configuration and easy troubleshooting with Infinity control
- 10-year parts limited warranty
- 20-year heat exchanger limited warranty
COMFORT® 80
Sinle-Stage Gas Furnace
58STA
Features & Benefits
- Up to 80% AFUE heating efficiency
- Single-stage operation
- Fixed-speed blower motor
- 10-year parts limited warranty
- 20-year heat exchanger limited warranty