What Is Emergency Heat? A Homeowner's Guide to the 'EM Heat' Setting

You glance at your thermostat and see two unfamiliar words glowing back at you: 'EM Heat'. A wave of uncertainty hits. Is your heat pump broken? Are you about to get a shockingly high electricity bill? That moment of confusion is common for homeowners, but you don't have to stay in the dark. Understanding what is emergency heat is the first step to taking control of your home's comfort and your energy spending. It’s the key to making smart, cost-effective decisions when the temperature drops.

In this straightforward guide, the trusted experts at BulletProof Air will demystify the 'EM Heat' setting for you. We’ll explain exactly what it does, the critical difference between 'auxiliary' and 'emergency' modes, and-most importantly-the specific situations where you should (and shouldn't) use it. By the end, you'll feel confident in managing your system and protecting your budget, ensuring your home remains the comfortable sanctuary it's meant to be.

Emergency Heat Explained: Your HVAC's Built-In Backup Plan

Think of the emergency heat setting on your thermostat like the spare tire in your car. You hope you never have to use it, but when your primary system fails on a cold day, it’s a critical backup designed to keep your family safe and warm. It's an essential feature found exclusively on HVAC systems that use a heat pump.

However, it’s crucial to understand that this is not a 'super heat' mode for warming your house faster. Using it unnecessarily will cause a major spike in your energy bill. The emergency heat function is a manual setting you activate only when your heat pump is completely broken and awaiting professional repair from a trusted team like BulletProof Air.

How a Heat Pump Normally Heats Your Home

Your heat pump is an incredibly efficient two-in-one system. In winter, it doesn't create heat; it moves it. The unit extracts warmth from the outside air-even when it's cold-and transfers it into your home. This process is highly energy-efficient, saving you money on utility bills. For a more technical look at How Heat Pumps Work, you can review foundational resources. However, as outdoor temperatures plummet, this heat transfer process becomes less effective, and the system may need assistance.

What is Emergency Heat, Exactly?

So, what is emergency heat? Unlike a heat pump that moves heat, the emergency heat system generates its own. In most all-electric systems, this is a set of electric resistance coils inside your air handler-similar to the glowing wires in a toaster. They heat up and the system's fan blows air over them to warm your home. For "dual fuel" systems, the emergency heat might be a backup gas or oil furnace that takes over completely.

Emergency Heat vs. Auxiliary Heat: The Critical Difference

Homeowners often confuse these two terms, but the difference is vital for your system's health and your wallet. It's a matter of manual control versus automatic function.

• Emergency Heat: You turn this on manually from your thermostat. It should only be used when your heat pump is malfunctioning or broken and cannot produce any heat.
• Auxiliary Heat: This turns on automatically. On very cold days, your heat pump may need help reaching your desired temperature. The auxiliary heat (often the same electric coils) kicks in to assist the heat pump, not replace it.

To add to the confusion, many thermostats display "EM Heat" or "AUX" when the auxiliary heat is running. Just remember: if you didn't switch it on yourself, it's likely the auxiliary heat performing its normal job.

How Emergency Heat Works (And Why It's So Expensive)

When you activate emergency heat, you're bypassing your heat pump's standard, high-efficiency operation and switching on a brute-force heating method. The difference in technology is the key to understanding both its effectiveness and its staggering cost. Think of it this way: your heat pump works smartly to move existing heat from the outside air into your home. Emergency heat works by creating intense heat from scratch.

Moving something is almost always easier and cheaper than making it. This fundamental difference is why understanding what is emergency heat is crucial for managing your utility bills and protecting your HVAC system.

The Science of Electric Resistance Heating

Inside your air handler, there are banks of metal coils, often called heat strips. When emergency heat is engaged, your system sends a massive amount of electricity directly through these coils. Much like the glowing elements in a toaster or an electric oven, these strips resist the electrical current, causing them to heat up to extreme temperatures. A fan then blows air over these superheated coils, delivering warm air into your home quickly and reliably, no matter how cold it is outside.

Calculating the Cost: A Real-World Example

The efficiency gap between a heat pump and electric heat strips is enormous. A standard heat pump might use 2-4 kilowatts (kW) of electricity per hour. In stark contrast, the electric heat strips can draw anywhere from 10 to 20 kW. According to the U.S. Department of Energy, a heat pump is a highly energy-efficient alternative to furnace or boiler systems, which makes its backup-the heat strips-seem even more power-hungry by comparison.

Let's put that into perspective with a simple example, assuming an electricity cost of $0.15 per kilowatt-hour (kWh):

• Standard Heat Pump (3 kW): 3 kW x 24 hours x $0.15/kWh = $10.80 per day
• Emergency Heat (15 kW): 15 kW x 24 hours x $0.15/kWh = $54.00 per day

Running your emergency heat for just a few days can add hundreds of dollars to your monthly bill. Furthermore, this heavy, continuous power draw can put a significant strain on your home's electrical circuits, which is another reason it's meant only for short-term, emergency use.

Is It Ever an Efficient Option?

Let's be perfectly clear: emergency heat is never an "efficient" choice. It is a necessary one. When your primary system fails during a cold snap, its only goal is to provide reliable heat to protect your home's plumbing from freezing and keep your family safe. It's a powerful but expensive safety net. If you find yourself relying on it, the most efficient decision you can make is to call a professional for immediate repairs.

Worried about high energy bills or your system's reliability? Schedule an HVAC tune-up today.

When to Use Emergency Heat: A Clear Checklist for Homeowners

When your heat pump fails on a cold night, the situation can feel stressful. Your first instinct might be to flip any switch that promises warmth, but using your emergency heat setting incorrectly can lead to sky-high energy bills and may not solve the underlying problem. Understanding what is emergency heat for-a temporary backup during a complete system failure-is crucial. This guide provides a clear, no-panic checklist to help you make the right call and protect your home and your HVAC system.

DO Manually Turn On Emergency Heat If...

Think of this setting as the spare tire for your HVAC system-it's for true emergencies only. You are facing a legitimate system failure and should activate emergency heat if you notice any of the following signs:

• Your heat pump is not running at all. If you hear no sound from the outdoor unit and feel no air moving through your vents, your primary heating source has failed.
• The outdoor unit is encased in a solid block of ice. A thin layer of frost is normal, but a thick, solid shell of ice indicates a serious malfunction with the defrost cycle.
• The system is blowing cold air continuously. If your thermostat is set to 'Heat' but only cold air is coming out after 10-15 minutes, the heat pump isn't working.
• You hear loud, grinding, or banging noises. These sounds often signal a critical mechanical failure in the outdoor unit that requires an immediate shutdown to prevent further damage.

DO NOT Use Emergency Heat Just Because...

Using this mode as a "heat booster" is an expensive mistake. It relies solely on the electric resistance heat strips, which consume a massive amount of energy. Avoid using it in these common situations:

• It feels a little cold in the house. Heat pumps work more gradually than furnaces. Give your system adequate time to reach the set temperature, especially on very cold days.
• You want to heat the house faster. Emergency heat is not a turbo button. It will not warm your home significantly faster and will drastically increase your electricity usage.
• You see the 'AUX' or 'EM' light come on briefly. This is normal. It means your auxiliary heat is temporarily assisting the heat pump during a defrost cycle or when it's struggling to keep up with extreme cold. It will turn off on its own.

Your First Step in an Emergency

If you've confirmed a true system failure based on our checklist, your priority is to restore warmth safely while preventing more damage. Take these three steps immediately:

1. Turn on the EM Heat setting on your thermostat to activate the backup heat strips.
2. Turn off the circuit breaker connected to your outdoor heat pump unit. This prevents the unit from trying to run while damaged.
3. Call a professional HVAC technician for emergency service. The team at BulletProof Air is available 24/7 to diagnose the problem and restore your primary heating system right the first time.

Troubleshooting: What to Do Before You Call for Service

Seeing the 'EM Heat' light on your thermostat can be alarming, but don't panic. In many cases, the cause is a simple issue you can safely identify and fix yourself, saving you the time and expense of a service call. At BulletProof Air, we believe in empowering homeowners. Before you call, run through these quick diagnostic checks to see if you can restore your system to normal operation.

If these steps don't help, you'll have valuable information to share with our technicians, allowing for a faster, more accurate repair. This is the first step in understanding not just what is emergency heat, but why your system has activated it.

Check Your Thermostat Settings

Sometimes, the solution is right at your fingertips. An incorrect setting is a common reason for heating issues. Take a moment to verify the following:

• Mode Selection: Ensure your thermostat is set to ‘Heat’ mode. It's easy to accidentally leave it on ‘Cool’ or ‘Off’.
• Temperature Setting: Confirm that the target temperature is set at least a few degrees higher than the current room temperature. Your system won't turn on if it thinks the room is already warm enough.
• Accidental Activation: Double-check that the ‘Emergency Heat’ setting wasn't switched on by mistake. On some models, this can be a simple switch or button that's easy to bump.

Inspect Your Air Filter and Vents

Your HVAC system needs to breathe. Restricted airflow is a primary cause of heat pump malfunctions, which can force your system into emergency mode. First, check your system's air filter. If it’s clogged with a thick layer of dust and debris, replace it immediately. A dirty filter suffocates your system. Next, walk through your home and ensure all air vents and registers are open and not blocked by furniture, rugs, or curtains.

Look at Your Outdoor Unit

Your outdoor heat pump unit is critical to the heating process. While you should never open the unit yourself, a quick visual inspection can reveal a lot. Check for any heavy debris like fallen leaves or branches that might be blocking the unit and restricting airflow. Listen for any unusual grinding or clanking noises when it attempts to run, as this signals a mechanical problem that requires a professional.

If you’ve performed these checks and the 'EM Heat' light is still on, it’s time to call in the experts. Your system is indicating a problem that needs professional diagnosis. Don't delay-your comfort and safety are our top priority. Call BulletProof Air 24/7 for fast, reliable service to restore your home to the sanctuary it should be.

Preventing HVAC Emergencies: Keeping Your Heat Pump Healthy

Understanding what is emergency heat is critical, but the ultimate goal is to ensure you never have to rely on it. Using your emergency heat setting is often a last resort, signaling that your heat pump is struggling or has failed entirely. This is almost always a preventable situation. Proactive maintenance is the key to avoiding costly emergency repairs, sky-high energy bills, and the stress of a system breakdown when you need it most.

By shifting from a reactive mindset to a preventative one, you protect your investment, extend the life of your HVAC system, and guarantee your family’s comfort. A healthy heat pump is a reliable heat pump.

The Importance of Regular Maintenance

The single most effective way to prevent an HVAC emergency is through regular, professional maintenance. A certified technician can spot small issues before they escalate into catastrophic failures. During a tune-up, our experts perform critical checks on your system, including verifying refrigerant levels, tightening electrical connections, and cleaning essential components. In Southwest Florida’s demanding climate, this isn't a luxury-it's a necessity to keep your system running efficiently and reliably.

Simple DIY Tasks for Homeowners

While professional service is crucial, there are simple steps you can take to support your system's health between tune-ups:

• Change Your Air Filter: A clogged filter restricts airflow, forcing your system to work harder. Replace it every 1-3 months.
• Clear the Outdoor Unit: Keep the area around your outdoor condenser free of leaves, grass clippings, and other debris to ensure proper airflow.
• Gently Rinse the Coils: After turning off the power at the breaker, you can use a garden hose to gently rinse dirt from the outdoor unit's fins. Always consult your owner's manual first.

When to Schedule a Professional Tune-Up

To ensure your heat pump is prepared for any weather, we recommend scheduling professional service twice a year: once in the spring before the cooling season and again in the fall before the heat is needed. This proactive approach is the best way to avoid asking "what is emergency heat" in a panic. A well-maintained system is your first line of defense. Don't wait for a breakdown to take action. Explore our BulletProof maintenance plans.

From Understanding to Action: Your Partner in HVAC Emergencies

Understanding your HVAC system is the first step toward preventing a crisis. You now know that your 'EM Heat' setting is a powerful but costly backup designed for true emergencies, not a long-term solution for a failing heat pump. Ultimately, knowing what is emergency heat is about being prepared for the unexpected and protecting your home from a sudden cold snap.

But when preparation isn't enough and your heat pump gives out, you need a fast, dependable solution. Don't let a system failure leave your family shivering. The expert, highly-trained technicians at BulletProof Air are on call and ready to restore your comfort without delay.

Facing a heat pump failure? Call BulletProof Air 24/7 for fast, expert emergency repairs! With our guaranteed fast response times in Sarasota and Bradenton, help is always just a phone call away. We’ll get the job done right the first time, restoring your home to the warm, comfortable sanctuary it should be.

Frequently Asked Questions About Emergency Heat

How long can I safely run my system on emergency heat?

Think of emergency heat as a temporary lifeline, not a long-term solution. You should only run it for a few hours, or a day at most, while you wait for a professional technician. Extended use leads to extremely high energy bills and can put unnecessary strain on your HVAC system's internal components. Your top priority should be to schedule a repair without delay to get your heat pump running efficiently again and restore your home's comfort.

Will emergency heat use significantly more electricity than my normal heat?

Yes, absolutely. Using your system’s emergency heat will cause a significant and immediate spike in your electricity consumption. This is because it bypasses your highly efficient heat pump and instead activates electric resistance coils-similar to the ones in a toaster. This method of generating heat is far less efficient and much more costly. To protect your wallet from a shocking utility bill, it’s critical to have the underlying problem diagnosed and fixed fast.

What temperature should I set my thermostat to when using emergency heat?

When your system is in emergency heat mode, set your thermostat to a conservative but safe temperature, such as 65-68°F. The goal is not to achieve maximum comfort, but to protect your home and pipes from freezing while minimizing the extreme energy costs associated with this setting. Setting it any higher will only accelerate your electricity usage. Once you’ve set a safe temperature, your next call should be to a trusted HVAC technician for a fast repair.

Why is my heat pump blowing cold air?

A heat pump blowing cold air is a primary sign that it's time to switch to the emergency setting. This issue often stems from the unit being stuck in a defrost cycle, a refrigerant leak, or a problem with the outdoor fan or compressor. While understanding what is emergency heat helps you stay warm temporarily, it doesn't fix the root cause. A professional diagnosis is essential to identify the exact failure and get your system back to operating safely and efficiently.

Can I turn off the emergency heat setting myself once the problem is fixed?

Yes, you can and should turn off the emergency heat setting once the issue with your heat pump is professionally resolved. On most thermostats, this is a straightforward process: simply switch the system mode from “Emergency Heat” or “EM Heat” back to the normal “Heat” setting. Do not switch it back until a certified technician has confirmed that your heat pump is fully repaired and functioning correctly, otherwise, you may risk further damage.

Is it normal for my heat pump to be covered in a light frost?

A light, even layer of white frost on your outdoor unit is perfectly normal during cold, humid weather. Your heat pump is designed to run a defrost cycle periodically to melt it away. However, if you see the unit encased in a thick sheet of ice, or if the ice isn't melting, that indicates a serious problem. This could be caused by blocked airflow or a refrigerant issue, and it requires immediate professional attention to prevent damage.