Two Stage Gas Furnace Operation

Two stage furnaces also known as dual stage furnaces can run at two different settings.

Two stage gas furnace operation.

Carrier gas furnaces offer a model to suit every need with intelligent multi stage variable speed models in our premium infinity series deluxe two stage choices in our performance series and 90 afue efficient models in our value driven comfort series. If a technician is to properly troubleshoot a gas furnace he needs to know the proper sequence of operation for the particular furnace he is troubleshooting. Gas furnaces sequence of operation troubleshooting. A full stop or at maximum.

In this video i go over. Two stage heating eliminates the temperature swings associated with standard furnaces regulating temperature to within as little as one degree of the thermostat setting. Simply put when it is only moderately cold inside then the furnace s control board opens the fuel control valve to the partially open position and heats the house to the desired temperature before turning off. This furnace turns either on or off.

How a two stage furnace works. Additionally the test will include the. Two stage furnaces start in the first stage when the amount of heat required is lower instead of reaching full capacity all at once. Our forced air units can keep your home warm with models that automatically.

But more importantly remember this changed in 2019. A gas furnace made in the early 1970s typically has an afue of about 65 percent. These furnaces have a two stage gas valve and a variable speed blower motor. A two stage furnace works by using a different set of programming than a normal one stage furnace.

There is no middle ground. The test will include ratios from low fire to high fire in this test. On off time for 2 stage or modulating furnace this will include the time the burner ignite to the burner extinguishes. Annual burner operating hours compared to annual energy consumption.

These motors were not new. To understand a single stage furnace s operation imagine traveling to a destination in a car whose accelerator regulates the speed at either of two settings. In gas furnace troubleshooting i believe the most common furnace to fail is the furnace that. You could buy a two stage furnace with an ecm motor for over 15 years.

Gas furnaces sequence of operation why is furnace sequence of operation important. Are the components any different. Instead of being either open or closed the gas valve can also be partly open. The blower fan can adjust its speed to meet your heating needs efficiency.

The lowest efficiency allowed by law for new gas furnaces is 78 percent and some new models achieve 97 percent. And manufacturers and contractors have been pushing the save you money claim for over 20 years. On is the highest flame setting and thus blows at its hottest level.