Emergency Heat: What Is It, and When Should You Use It?
Many modern homes use heat pumps to efficiently heat and cool. But these systems have their limits. That’s where emergency heat comes in.
Emergency heat is a backup system designed to keep your home comfortable and prevent damage if your heat pump fails or when temperatures plummet. Understanding when to use it is key, though. Many homeowners don’t know what emergency heat means or how to use it properly.
Using emergency heat at the wrong time can lead to significantly higher energy bills and put a strain on your system. This guide will explain what emergency heat is, how it works, and when you should (and shouldn’t) use it. We’ll help you make informed decisions about your HVAC system and energy consumption so that you can keep your home comfortable without breaking the bank.
What does “emergency heat” mean?
Emergency heat is a backup system that kicks in when your regular heating system can’t keep up. Usually, this means your heat pump isn’t working like it should.
You’ll probably need to use emergency heat when it’s extremely cold outside and the heat pump can’t pull enough warmth from the air. You might also need it if the heat pump breaks down – say, if the compressor fails or the coils freeze up.
It’s important to remember that emergency heat is only meant to be a temporary fix. You should only use it until you can get your heat pump repaired or the weather warms up. Running emergency heat for too long can cost you a lot of money and put extra stress on your backup system.
How Heat Pumps Work and Their Limitations
To really understand the “emergency heat” setting on your thermostat, it helps to know a little about how heat pumps work. Here’s the lowdown:
The Basics of Heat Pump Operation
Heat pumps don’t actually generate heat. Instead, they move heat from one place to another. In the winter, they pull heat from the outside air and send it inside your house.
Even when it’s cold out, the refrigerant inside the heat pump can absorb heat from the outside air. The compressor then raises the pressure and temperature of the refrigerant, allowing it to release heat into your home.
Limitations in Cold Weather
The colder it gets outside, the less heat a heat pump can pull from the air. At some point, usually between 0 and 35 degrees Fahrenheit, the heat pump won’t be able to keep your house warm enough.
Also, heat pumps can ice up on the outside, so they have to go into “defrost” mode from time to time. When that happens, the heat pump temporarily switches to cooling mode and uses electric resistance heat to warm the coils.
Emergency Heat vs. Auxiliary Heat: What’s the Difference?
Many people get “emergency heat” and “auxiliary heat” mixed up, so let’s clear things up:
Auxiliary Heat: Automatic Boost
Auxiliary heat is a supplemental system that kicks in automatically when your heat pump needs a little help. It works with the heat pump to keep your home at the temperature you set.
Emergency Heat: Manual Override
Emergency heat is a setting you turn on manually. When you activate it, you’re completely bypassing the heat pump and relying entirely on the backup heating system. You should only use this setting if your heat pump breaks down or if it’s so cold outside that the auxiliary heat isn’t enough.
When to Use Each One
Auxiliary heat turns on by itself when the weather is cold enough. Emergency heat is only for emergencies or when the heat pump isn’t working anymore.
The mechanics of emergency heat: How it works
So, how does emergency heat keep you from freezing?
Electric resistance heat: The common backup
Most of the time, emergency heat relies on electric resistance heat, often in the form of heat strips. These strips are located in your air handler, and they work by passing electricity through a material that resists the flow of electricity. This heats the strip, and your blower fan pushes air across the heated strip to warm your house.
One downside to emergency heat is that electric resistance heat is a lot less energy efficient than a heat pump. It takes more electricity to produce the same amount of heat.
Alternative backup systems
Some dual-fuel systems use a gas or oil furnace as a backup for your heat pump. These systems are more efficient than electric resistance heat, so they’re a good choice if efficiency is important to you.
Why is emergency heat so expensive?
Emergency heat guzzles energy like crazy, especially when it uses electric resistance heat. This means you’ll see a major spike in your electricity bill.
Heat pumps are way more efficient, typically two to four times better than electric resistance. For every bit of electricity a heat pump uses, it kicks out two to four times more heat.
Let’s break it down with some numbers:
- Running emergency heat can add around $20 to your bill per day compared to regular heat.
- A heat pump can heat your home for $0.02–$0.05 per 1,000 BTUs. Electric resistance? That’ll cost you around $0.12 per 1,000 BTUs.
The bottom line? Only flip on emergency heat when you absolutely have to. Get your heat pump fixed ASAP if it’s acting up, so you don’t have to rely on that energy-hungry emergency setting.
When to suspect a heat pump problem
If you use a heat pump, you should be aware of the warning signs of a potential issue. If you notice any of the following, you may need to call a professional for service:
- Unusual noises. Loud banging, hissing, or grinding could mean something’s wrong with the compressor or another part. If you hear new or strange noises, it’s a good idea to get it checked out.
- Insufficient heating. If your heat pump is running but your house isn’t getting warm enough, there might be a refrigerant leak or a problem with the compressor.
- Frozen coils. Too much ice on the outdoor coils can stop the heat pump from working right.
- Frequent cycling. If the heat pump keeps turning on and off, the thermostat could be malfunctioning, or there could be an issue with the system.
- High energy bills. If your energy bills suddenly go up for no clear reason, the heat pump might not be working efficiently.
Troubleshooting and maintenance tips
If your heat pump isn’t working efficiently, here are a few things you can try yourself before calling a professional.
Simple troubleshooting steps
- Check the thermostat. Make sure the thermostat is set to “heat” and that the temperature is set higher than the current room temperature.
- Check the air filter. A dirty air filter can restrict airflow and lower your heat pump’s efficiency. Change the furnace filter when it’s dirty.
- Clear obstructions. Make sure there’s no debris or anything blocking the outdoor unit.
Importance of regular maintenance
The best way to keep your heat pump running efficiently is to schedule routine maintenance with a qualified HVAC technician.
- Professional inspections. A technician can inspect your system, identify leaks, and address any potential problems before they turn into major repairs.
Frequently Asked Questions
What temperature to switch to emergency heat
There’s no specific temperature that dictates when to switch to emergency heat. It’s designed to be used when your heat pump is struggling to provide adequate warmth, generally when the outside temperature drops significantly, usually below freezing, or when the heat pump malfunctions. If your home isn’t reaching the set temperature and the heat pump is running constantly, that’s a good sign to consider switching to emergency heat.
Is it OK to run emergency heat
Yes, it is okay to run emergency heat, but only when absolutely necessary. Think of it as a temporary solution, not a long-term heating strategy. Emergency heat relies on electric resistance coils, which are much less energy-efficient than your heat pump. Using it for extended periods will result in a significantly higher energy bill. If you find yourself relying on it frequently, it’s time to have your heat pump inspected by a qualified HVAC technician. There may be an underlying issue preventing it from working efficiently.
To Conclude
Emergency heat is a great backup to have, but it’s not meant to be used all the time because it uses a lot of energy.
Knowing the difference between emergency heat and auxiliary heat will help you get the most out of your HVAC system and help you save money on your energy bills.
To avoid using emergency heat, schedule annual HVAC inspections and take care of necessary repairs as soon as possible. With proper care and responsible use, you can keep your home warm and comfortable while keeping your energy costs under control.