Furnace rolls work in some of the harshest environments. They will typically see temperatures in excess of 500 degrees Fahrenheit for years at a time. Materials used are made to withstand this criteria, so they are also difficult to machine. Let’s take a look at some of the different types of gas furnaces that furnace rolls are found in.
Modulating (or Variable Speed) Furnace
This furnace adjusts its flame incrementally so that the true temperature never varies more than 1 or 2 degrees from the thermostat’s target temperature. In terms of comfort, it is the most comfortable gas furnace you can buy. Modulating gas furnaces are among the most energy-efficient furnaces and are rated at 98% efficiency.
Two-Stage or Dual-Stage Furnace
The two-stage furnace is not as complex than the modulating furnace but better than the single stage furnace. Rather than a simple on/off operation, its flame can be on/high, on/low, or off. Adding this second flame setting makes a dramatic difference in energy costs.
Single Stage Furnace
With a single stage furnace, the gas flame is either on or off. Because of that, the furnace waits for the temperature in the house to get cold before firing on. Then, the furnace rams the house full of heat until the thermostat shuts the system down.