Alternate Heat Stage 2 Nest (2024)

FAQs

What does heat stage 2 mean on a Nest? ›

What is meant by Stage Two heating? When the thermostat on a dual-stage furnace reads “Stage 2,” it implies that the furnace is operating at the higher setting, giving you 100 percent of its capacity. Usually, the lower setting of a dual-stage furnace is sufficient to provide household comfort almost 80% of the time.

For conventional heating and cooling the Nest Thermostat will show “HEAT STAGE 2”, “HEAT STAGE 3”, or “COOL STAGE 2” if additional stages are activated. If a dual fuel system is installed, the Nest Thermostat will display “ALT. HEAT” or “ALT. HEAT STAGE 2” if the alternate heating sources are engaged.

The supplemental heat is also referred to as second-stage or back-up heating, with first-stage being the Heat Pump only. Emergency Heat is when you use your supplemental heat (2nd stage) by itself, without the use of your heat pump (1st stage heat).

If the set point is greater than 2 degrees from the current room temperature, it will activate stage 2 cooling. Once it the room temperature gets within 1 degree, it will switch back to stage 1 cooling.

Stage 2 simply means that thermostat has engaged second stage of heating because temperature has droped more than 2 degrees below set temperature.

The first stage (low fire) is the primary one that runs about 75% of the time or more. The second stage (high fire) will typically activate when it's icy cold outside. It will also turn on if the thermostat senses it needs to raise the temperature more than two degrees. We'll return to our BTU example.

The Emergency Heat or Auxiliary Heat setting is the second stage of your heating system that is used when the temperature is too low for the heat pump to be able to remove heat from outside, typically below 35 degrees Fahrenheit.

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 household heating demands 80% of the time, a two-stage unit runs for longer periods and provides more even heat distribution.

Since two-stage furnaces make better use of energy, they cost less to run. If you own a two-stage furnace for many years, you'll save hundreds of dollars that you'd otherwise be spending on heating costs. That's why two-stage furnaces are often a better bet for homeowners thinking on a long-term scale.

Because EM Heat uses far more energy than a properly functioning heat pump-based system, the EM heat setting's long-term use would be quite expensive and should be avoided. This is because backup systems, such as an electric strip or gas furnace, are less efficient at pulling heat.

How long should auxiliary heat run? ›

If the auxiliary heat runs either every time you turn your system on, an unusual amount of time (such as longer than 30 minutes or all day), or does not turn off, you should have your system evaluated by an HVAC pro.

Heat stage 2 is supposed to give you 100% of your heaters capacity.

Basically, a two-stage air conditioner will, by default, run on the lower setting until it gets too hot outside. Then it runs on the high setting to make sure you stay comfortable. “What are the benefits of getting the two-stage over the single-stage air conditioner?”

Conventional systems: Nest Learning Thermostat (4th gen) can support up to 2 stages of cooling and up to 3 stages of heating. Heat pump systems: Nest Learning Thermostat (4th gen) can support 4 stages of heating, consisting of 2 stages heat pump heating and 2 stages of alternate heating.

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 household heating demands 80% of the time, a two-stage unit runs for longer periods and provides more even heat distribution.

Since two-stage furnaces make better use of energy, they cost less to run. If you own a two-stage furnace for many years, you'll save hundreds of dollars that you'd otherwise be spending on heating costs. That's why two-stage furnaces are often a better bet for homeowners thinking on a long-term scale.

The heat pump will cycle on and off at low speed — first stage — for the majority of the year, until it gets really cold or hot out and needs to jump to high speed — second stage — to keep up. The heat pump will automatically jump between stages in response to the temperature that you set on the thermostat.