When Should Emergency Heat Be Used?

Q: When should I use Emergency Heat on my thermostat?

A: Use Emergency Heat (EM Heat) only when your heat pump is not operating correctly and you need temporary heat until it can be repaired. Emergency Heat typically shuts off the heat pump compressor and runs only the backup heat source. It is not meant for normal day-to-day heating and can increase energy use significantly if left on longer than needed.

Common Situations That Make Homeowners Ask About Emergency Heat

• Thermostat shows an EM Heat option and you are not sure what it does
• Your house is cold and the heat pump is not keeping up
• The outdoor unit is not running in heat mode
• Your heat pump is iced over and not recovering
• You accidentally switched to Emergency Heat and now worry you did something wrong
• Your electric bill jumped and you think EM Heat may have been left on
• You see AUX heat often and are unsure if that is the same thing

Safety First

• Turn the thermostat to OFF before opening any access panels.
• Shut off the breaker if checking the filter or indoor access panel.
• Do not handle wiring, capacitors, contactors, or control boards.
• Do not force the system to keep running if it is tripping breakers, buzzing loudly, or shutting down repeatedly.
• If you smell burning or see damaged wiring, stop and call for service.

Quick Checks You Can Do First

1. Confirm system type: Emergency Heat is a heat pump thermostat feature. If you do not have a heat pump, this mode may not apply.
2. Check thermostat mode: Make sure you are in HEAT, not EM HEAT, unless you intentionally switched it.
3. Check the air filter: A clogged filter can make the system struggle and look worse than it is.
4. Check breakers: Confirm the indoor and outdoor units have power.
5. Look at the outdoor unit: If it is not running, heavily iced over, or obviously struggling, the system may need service.
6. Avoid large thermostat jumps: Big setpoint increases can trigger backup heat behavior and confuse the diagnosis.

What Emergency Heat Does

On most heat pump systems, Emergency Heat is a manual thermostat setting that tells the system to stop using the heat pump compressor and run only the backup heat source. In many Florida homes, that backup source is electric heat strips inside the air handler. In some systems, the backup heat could be a furnace.

This mode exists so you can still have heat if the heat pump portion of the system is not working properly.

When You Should Use Emergency Heat

The heat pump is not running and you need temporary heat

If the thermostat is calling for heat and the outdoor unit is not operating correctly, Emergency Heat can provide temporary indoor heat while you wait for service.

The heat pump is malfunctioning and blowing cool air in heat mode

If the system is clearly not heating correctly and you need to keep the home warm until repair, EM Heat may be appropriate.

The outdoor unit is severely iced over and not defrosting

Light frost can be normal, but heavy ice that does not clear is not. If the unit is not recovering and the home needs heat, Emergency Heat can be used temporarily while service is scheduled.

You were instructed to use it by a technician while waiting on repair

Sometimes a technician will recommend temporary Emergency Heat use based on a known system fault until parts or follow-up service are completed.

When You Should Not Use Emergency Heat

As a normal heating mode

EM Heat is not the normal way to heat a home with a heat pump. It is a backup mode for problem situations.

Just because it is a little cold outside

Your heat pump and AUX heat controls are designed to manage normal cold-weather operation automatically. Manually switching to EM Heat is usually unnecessary in typical conditions.

To heat the home faster after turning the thermostat up

Many thermostats will call for auxiliary heat automatically when needed. Manually using Emergency Heat usually increases cost and is not the right “boost mode.”

All season long because the thermostat has the option

If left on by accident, Emergency Heat can drive up electric bills and hide an actual heat pump problem.

Emergency Heat vs AUX Heat

AUX heat

Automatic backup heat that helps the heat pump when needed. This can happen during cold weather, defrost cycles, or recovery after a thermostat setback.

Emergency Heat

Manual thermostat mode that usually locks out the heat pump compressor and runs backup heat only.

This difference is one of the biggest reasons homeowners get confused. Seeing AUX heat is often normal. Turning on Emergency Heat manually is usually only for a real equipment problem.

Signs Emergency Heat May Be On Accidentally

• Thermostat is set to EM HEAT but you did not mean to choose it
• Outdoor unit is not running even though the home is heating
• Electric bill is higher than expected during heating weather
• The system seems to heat, but not in the usual way you are used to hearing/seeing

Florida Homeowner Context

In Florida, Emergency Heat usually should be used rarely. Most of the time, your heat pump should handle heating demand on its own, with automatic AUX heat support when needed. If you find yourself using EM Heat often, that is a sign the heat pump system may need inspection.

Florida cold snaps can still expose heat pump issues, especially if the system has airflow problems, deferred maintenance, thermostat setup issues, or outdoor unit problems.

What to Do If You Need Emergency Heat

1. Switch the thermostat to EM HEAT only if the heat pump is not operating properly and you need temporary heat.
2. Set a reasonable temperature and avoid large jumps.
3. Schedule service as soon as possible.
4. Turn Emergency Heat off after the system is repaired or when instructed by your technician.
5. Do not leave EM Heat on long-term unless a technician specifically directs you to do so.

What Beacon Usually Checks

When homeowners ask about Emergency Heat, our friendly technicians in yellow check whether the thermostat is being used correctly and whether the heat pump itself is operating normally.

• Thermostat mode and programming
• Whether the system is in HEAT, AUX heat operation, or Emergency Heat mode
• Indoor airflow and filter condition
• Outdoor unit operation and visible icing issues
• Electrical and control behavior
• Whether backup heat is assisting normally or covering up a fault
• Comfort performance and run-time clues

When to Call Beacon

If your heat pump is not heating well, the outdoor unit is not running, the system is iced over, or you are relying on Emergency Heat to stay comfortable, Beacon can help diagnose the cause and explain what needs repair.

Request Service
(352) 726-7530
www.BeaconSaves.com

Prevent This Next Time

• Schedule routine heat pump maintenance
• Change filters regularly to protect airflow
• Keep the outdoor unit clear of leaves and overgrowth
• Watch for repeated AUX heat or icing issues and address them early
• Check thermostat mode after cold snaps or power outages
• Learn the difference between AUX heat and Emergency Heat before you need it

📍 Contact Beacon Services & Appliances
📞 (352) 726-7530
🌐 www.BeaconSaves.com.