Difference Between Emergency Heat and Thermostat Heat: What Homeowners and Building Managers Need to Know: When temperatures drop, heating systems become the backbone of comfort and safety in homes and buildings. Yet many property owners are unclear about the difference between emergency heat and regular thermostat-controlled heat. Misunderstanding the two can lead to higher energy bills, reduced system efficiency, and even premature equipment wear. This article breaks down the essentials so you can make informed decisions about when and how to use these modes effectively.
What Is Thermostat Heat?
Thermostat heat, also referred to as “normal heat,” is the standard operating mode of your heating system. When you set the thermostat to your desired temperature, it automatically signals the system to engage as needed to maintain comfort.
For heat pumps and conventional furnaces, this process is seamless:
- The thermostat monitors indoor temperature.
- If the temperature dips below the set point, the thermostat activates the heat pump or furnace.
- Once the room reaches the desired temperature, the system cycles off.
Thermostat-controlled heating is designed to maximize energy efficiency, reducing unnecessary fuel or electricity use while maintaining consistent indoor comfort. In most climates, this mode is all you need throughout the heating season.
What Is Emergency Heat?
Emergency heat, sometimes labeled as “EM Heat” on thermostats, is a backup heating mode. It is primarily used in systems that rely on heat pumps.
Here’s how it works:
A heat pump extracts warmth from the outside air, even in cold weather, and transfers it indoors.
When outdoor temperatures fall extremely low, the heat pump may struggle to maintain efficiency.
In these situations, emergency heat engages electric resistance coils or a gas/oil furnace as a secondary heat source.
Emergency heat does not rely on the heat pump at all—it bypasses it entirely. That’s why it is typically less efficient and more expensive to run.
Key Differences Between Emergency Heat and Thermostat Heat
| Feature | Thermostat Heat (Normal) | Emergency Heat |
|---|---|---|
| Purpose | Everyday heating mode | Backup heating mode when the heat pump can’t keep up or fails |
| Energy Source | Heat pump (electric) or primary furnace | Electric resistance coils, gas, or oil |
| Efficiency | High efficiency, cost-effective | Low efficiency, higher operating costs |
| Activation | Automatic through thermostat settings | Manual selection on thermostat |
| Use Case | Normal winter conditions | Extremely cold weather or system malfunction |
When Should You Use Emergency Heat?
Emergency heat should not be your default heating method. Instead, use it only in the following cases:
- Heat Pump Failure: If your heat pump isn’t functioning due to a mechanical issue, emergency heat ensures your space remains warm until repairs are made.
- Extreme Cold Weather: In climates where outdoor temperatures drop well below freezing, the heat pump may not extract enough warmth. Emergency heat provides reliable backup.
- System Testing: Some technicians may use the emergency heat setting during service visits to ensure backup systems are working correctly.
Using emergency heat outside of these scenarios can lead to unnecessarily high utility bills.
Energy Efficiency and Cost Implications
The most significant difference between the two modes comes down to efficiency.
Thermostat-controlled heat (via heat pump) is designed to deliver maximum comfort at a fraction of the cost, using outdoor air as the main energy source.
Emergency heat, by contrast, requires much more electricity (for resistance heating) or fuel (for backup furnaces), making it far more expensive.
For example, an electric resistance backup system can cost two to three times more to run compared to a heat pump operating in normal thermostat mode.
Practical Advice for Homeowners and Building Managers
Trust your thermostat settings: Leave the system on “Heat” or “Auto Heat” for everyday operation.
Reserve emergency heat for emergencies: Do not switch to EM Heat unless your heat pump is failing or temperatures are extreme.
Monitor energy bills: A sudden spike may indicate the system is running on backup heat more often than it should.
Schedule regular maintenance: Annual service ensures both your heat pump and backup heat sources are functioning properly.
Educate tenants and staff: In multi-unit buildings, clear instructions can prevent misuse of emergency heat.
Conclusion
The difference between emergency heat and thermostat heat lies in purpose, efficiency, and cost. Thermostat-controlled heating is the everyday, energy-efficient mode, while emergency heat should only be used in rare circumstances when the heat pump cannot perform.
Service ac jakarta, For homeowners and building managers, knowing how to use these settings wisely can mean the difference between manageable winter energy bills and unnecessary expenses. Keep your system well-maintained, and let the thermostat do its job—reserve emergency heat for when you truly need it.
