Skip to main content
Knowledge Base

How do Auxiliary Heat and Emergency Mode work with an Alarm.com Smart Thermostat?

  1. Last updated
  2. Save as PDF

Auxiliary Heat

What is Auxiliary Heat?

Auxiliary Heat refers to the use of another heat source in a heat pump system that is not the heat pump. Often, this is an electric or gas heat source that is meant to provide more powerful heating for short periods when the heat pump is unable to heat to the desired setpoint quickly enough.

Note: Since Auxiliary Heat sources are only meant to supplement the heat pump, they are typically less powerful than similar dedicated heat sources (e.g., gas furnace) that would heat a building on their own.

When is Auxiliary Heat used?

The Alarm.com Smart Thermostats can use Auxiliary Heat based on the following:

  • Staging Delay - The amount of time before the next heating stage will turn on if the target setpoint has not been reached.
  • Heating Differential - The number of degrees below the Target Temp the Ambient Temp can drop before activating the next stage of heating. This works in conjunction with Staging Delay.
  • Balance Point - The minimum outdoor temperature at which the thermostat will use the heat pump as a heat source. If the outdoor temperature is below the Balance Point, the heat pump will not run, and only the Auxiliary Heat will be used.
     
    Note: Balance Point is only available for Alarm.com Smart Thermostats with firmware 1.50+. 
     
  • Emergency Mode - See below.
How should Auxiliary Heat sources be wired to the thermostat?

Auxiliary Heat sources are connected to the Alarm.com Smart Thermostats using the W terminals.

For information about how Auxiliary Heat works with non-Alarm.com thermostats, refer to the device manufacturer.

Emergency Mode

Emergency Heat is designed to heat the house quickly but energy inefficiently/expensively. Emergency Heat, labeled EMER, is specific to heat pump systems where the heat pump is bypassed and only Auxiliary Heat is used for heating.

Heat pumps become less effective at heating when the outside temperature gets too cold, so Emergency Mode bypasses the heat pump to heat the building quicker. This mode is meant to be used during the coldest days of the year in the relatively temperate climates where heat pumps are used.

Note: To mitigate the accidental/excessive use of Emergency Heat, this mode cannot be selected as a mode option when creating/editing a scene. 

EMER mode requires: 
  • Alarm.com Smart Thermostat (Smart Thermostat HD, ADC-T2000, and ADC-T3000) configured as Heat Pump 
  • At least one stage of Aux heat

Note: Auxiliary Heat sources are not as powerful as a dedicated furnace, so a system in Emergency Mode may need to use more energy to reach a desired setpoint/target temperature.

Put the Alarm.com Smart Thermostat into Emergency Mode
  1. Tap the screen on the Smart Thermostat.
  2. Tap Mode.
  3. In Mode, tap EMER.
  4. Tap Save.
  1. Press any button to wake the thermostat up.
  2. Press Mode at any time to change the mode.
    • The modes are HEAT, COOL, AUTO, EMER, and OFF.
  3. EMER mode is available for Heat Pump systems. Press and hold Mode while in Heat Mode to enter EMER.
  4. When in EMER mode, the display will read EMER when the thermostat wakes up and the HEAT icon will be displayed. Changing the mode will leave EMER mode.
  1. Press the Minus button.
  2. Select MODE.
    • The modes are HEAT, COOL, AUTO, EMER, and OFF.
    • The thermostat will only show the modes that are available based on the system configuration.
  3. Select EMER mode.
  4. When in EMER mode, the thermostat will flash EMER when the display wakes up, and it will show HEAT at the top of the screen. Changing the mode will leave EMER mode.
     
  5. Once in EMER mode, press the Up and Down buttons to adjust the desired setpoint.

Interested in Alarm.com?

Alarm.com technology is sold, installed, and serviced by licensed service providers near you.

 

Let's Get Started