You might have noticed an emergency heat button on your thermostat and wondered what it does. Emergency heat should only be used in emergency situations, and in this article, we’ll explain why.
Wondering what the emergency heat setting means for your HVAC system? It differs from regular heat mode and should only be used in emergencies, such as a faulty heat pump. Let’s dive into explaining the emergency heat setting and how it should be used.
What Is the Emergency Heat Setting?
The emergency heat mode shuts down the heat pump and stops it from extracting heat from outside air. This enables your HVAC system to use its auxiliary heat system, which is generally an oil or gas furnace or electric heat strip. If you have an electric heating system, the longer the emergency heat mode is on, the more costly it gets.
This manual override of your thermostat tells the HVAC system to stop using the heat pump entirely and instead rely on a backup heating source. This setting is for temporary, emergency use only, not everyday heating.
How Emergency Heat Differs from Regular Heat Mode
While both emergency heat mode and regular heat mode will effectively warm your home, they function differently.
In regular heat mode (normal operation), the heat pump does most of the work by extracting heat from outdoor air, even in cold weather. Auxiliary heat only activates automatically if needed. This mode is designed for energy efficiency and lower operating costs.
In the emergency heat setting, the heat pump is completely disabled. Heating will only come from the backup system. The emergency heat setting must be turned on manually and is significantly less efficient and more expensive to run. It’s intended only for short-term use.
How a Heat Pump Normally Heats a Home
A heat pump normally operates by moving heat rather than generating it. Even in cold weather, there is usable heat energy in the outdoor air. A heat pump captures the heat energy in outdoor air and moves it inside to warm your home.
Here’s a brief breakdown of the process:
Step 1: Heat is extracted from outdoor air
- The unit pulls in air from outside
- Refrigerant inside the system absorbs the heat from the air
Step 2: Refrigerant is compressed to increase heat
- The warmed refrigerant travels to the compressor
- Compression raises the refrigerant’s temperature and pressure
Step 3: Heat is distributed inside the home
- The hot refrigerant flows to the indoor coil
- Heat is transferred into your home’s air
Step 4: The cycle repeats
- After releasing the heat, the refrigerant cools
- It returns outdoors to collect more heat
When Should Emergency Heat be Used
You may be wondering when emergency heat should be used at all. There are a few instances when you should consider turning on emergency heat, including:
Heat Pump is Iced Over
If there’s thick buildup of ice on your outdoor heat pump and the unit is not defrosting on its own, you can turn on emergency heat. In these cases, airflow is blocked and heat output from the heat pump drops significantly.
The Heat Pump Is Malfunctioning
If your heat pump won’t turn on or the system is blowing cold air, you can turn on emergency heat to temporarily warm your home. If you’ve been advised by an HVAC technician to disable the heat pump to prevent damage, emergency heat is also needed until heat pump repairs can be made.
Extremely Cold Conditions
If temperatures drop below the system’s effective operating range, emergency heat may be needed. If you notice your heat pump is struggling to maintain indoor comfort, the emergency heat setting can be turned on temporarily.
When It Shouldn’t Be Used
In most situations, emergency heat should remain off. Using it when it’s not needed can cause strain and higher utility costs.
Normal Cold Weather
Heat pumps are designed to work effectively in normal cold weather. The system may run a bit longer, but that’s normal. Auxiliary heat will engage automatically, if required.
Faster or “Stronger” Heating
Let’s dispel a myth here: Emergency heat does not warm your home faster. So do not try to use it to get faster and stronger heating. It simply bypasses the heat pump and leads to higher energy usage without added comfort.
No System Issues
If your system is operating normally in cold weather and there’s no ice buildup, there’s no need for the emergency heat setting. With stable indoor temperatures, emergency heat only adds unnecessary cost.
Prevent Heat Pump Issues
To prevent heat pump issues, you should schedule regular maintenance. Routine maintenance by a professional prevents heat pump issues by keeping your system running smoothly.
An HVAC technician will usually inspect and clean the system’s coils, check refrigerant levels and pressure, test the defrost cycle, examine electrical connections, replace or clean air filters, and verify proper airflow and thermostat operation.
Benefits of routine maintenance:
- Improves system efficiency
- Reduces the risk of icing and defrost problems
- Extends your equipment’s lifespan
- Identifies issues before they become emergencies
- Prevents costly emergency heat usage
Schedule Maintenance Today
Want to avoid needing to use the emergency heat setting? Schedule routine maintenance and an annual heat pump inspection with Mercurio’s today. Our expert HVAC technicians will assess your system and identify any minor problems before they turn into major issues. Stay warm and comfortable all season long with Mercurio’s.
Call us today at (360) 499-2980 or schedule online. Our skilled HVAC experts are equipped and ready to assess your system today.
