Photo of a Missoula heat pump in Minnesota by Garden City Plumbing and Heating

Missoula Heating Contractors Explain Heat Pumps: Emergency VS Aux Heat

If you have a heat pump or are considering installing a heat pump in your Missoula, Montana home, understanding a few things will help you maximize its effectiveness and efficiency.  Before we get to our game of 20 questions, let’s take a quick look at heat pumps and how they work.

How do Heat Pumps work?

There are 2 types of heat pumps.  Ground source heat pumps are the gold standard of heating.  The earth stays at a generally consistent temperature throughout the year.  This is much warmer than the winter chill and much cooler than the summer heat.  This consistency is tapped into and used to heat homes in winter and cool homes in the summer.

Air-Sourced Heat pumps warm your home by pulling heat from the outdoor air and moving that heat to the indoor air.  It is surprising how much heat can be pulled from the great outdoors in the dead of winter.  In the summer, the system is reversed to pull heat out of the home and release it to the outside air.

When a heat pump system needs a boost, there are two possible backups that can come into play.  Emergency heat and Auxiliary heat are two processes that every homeowner with a heat pump should understand.  Let’s jump into our game of 20 questions to explore heat pumps and their backup systems! By the time we are done, you will be on the phone with your local Missoula heating contractor to have your new heat pump installed!  The first half of our game will explore heat pumps and find out if and when they will need a bit of help.

Bottom Limits of Heat Pumps according to Missoula Heating Contractors

1.   When the temperature is below 20 degrees Fahrenheit, will a heat pump work?

Yes, they do!  Recent technology has made Heat Pumps even more effective and efficient at lower temperatures than ever!

2.   What temperature is too cold for a heat pump?

The answer to this question really depends on when a heat pump was produced.  Back in the 80’s and 90’s, heat pumps struggled below freezing.  Nowadays, heat pumps are much more capable!  Heat pumps can work well below -10 degrees Fahrenheit!  And do so efficiently!

3.   At what temperature will a heat pump lose efficiency because it has to work so hard to keep my home warm?

The colder the outside temperature, the less efficient a heat pump will be.  As a guideline, at 10 degrees Fahrenheit, an average heat pump is still more energy efficient than an electric furnace or a space heater.  We start to see a reversal of efficiency between these different methods when we get down to negative 15 degrees Fahrenheit

4.   Will a ground-source heat pump be more effective than an air-source heat pump?

The ground maintains a relatively consistent and often warmer temperature than the above-air temperature in winter.  This means ground-source heat pumps will use the same small amount of electricity to get your home to the desired temperature year round, while air-source heat pumps will work harder at extreme temperatures.  Air-source heat pumps will still be efficient in the dead of winter, just not as efficient as a ground-source heat pumps.

5.   What are the disadvantages of ground source heat pumps?

Ground source heat pumps can have installation costs that will not occur with air source heat pumps.  Beyond these costs, the installation of a ground source heat pump can be disruptive to your lifestyle.  Your yard will have to be, at least partially, dug up in the process.   Lastly, if you do not have an open lot space large enough to bury the pipes, you will not be able to use it. 

6.   Why is my ground source heat pump using so much electricity?

Ground source heat pumps are one of the most efficient types of heat.  If your electric bill is spiking and you think it is being caused by your heat pump, it is likely because you need maintenance or a repair.  This could be as simple as a dirty filter or debris in the fan or as complex as needing to replace an entire unit.  This is why it is important to have your heat pump serviced yearly by a Missoula heating contractor.

7.   Will my heat pump be noticeably less efficient below a certain temperature?

It really depends on what model of heat pump you have.  If you have a heat pump specifically designed for cold weather climates, you will probably notice a slow, progressive growth in your electric bill as temperatures get below 20 degrees Fahrenheit.  But you should not see a large increase until you get below 0 degrees Fahrenheit.

8.   Would my heat pump work in Antarctica?

Antarctica is known as the coldest place on earth.  Well, we’re here to tell you that heat pumps not only work in Antarctica but are currently being used in Antarctica!  If the guys in the coldest place on earth rely on it, Missoula heating contractors feel pretty confident it will serve your home just as well!

9.   What are the cons of an air source heat pump?

An air-source heat pump will keep your home cozy and warm, but it might not be as quick as other heat sources.  It can take half an hour to obtain the heat from outside to bring into the home.  This slow sourcing can cause heat pumps to run with fewer breaks on those colder winter days.

10.   Just because a heat pump can work in super cold temperatures, would it be better to have another source of heat to switch to so that it is not overworked?

Heat pump technology has come a long way!  Heat pumps can more effectively heat a home in colder temperatures than even just a decade ago.  Providing a helping hand to a heat pump to have a comfortable home is an option many people explore.  Read on to figure out how it can work!

Emergency Heat VS Aux Heat

There can come a point where heat pumps are simply not able to pull enough heat to warm a home efficiently. This is where backup systems come in.  Let’s explore Emergency Heat vs Auxiliary Heat for the rest of our 20 questions!

1.    What is Emergency heat with my heat pump?

Emergency heat is turned on manually by the occupant when the heat pump shuts down or needs to be shut down.  This feature is to prevent further damage to your heat pump if it needs a break. Typically, an electric heat strip is used to provide emergency heat.  Sometimes, homeowners choose to use a gas furnace to produce the extra heat needed in a backup situation. 

2.   What is auxiliary heat?

Auxiliary heat is a feature to go along with a heat pump system that boosts the heat production in your home. It will come on automatically when there is a sudden drop in temperature and the heat pump cannot keep up with the heat demand.  Electric heat strips or a gas furnace are the typical sources of auxiliary heat when winter quickly brings those coldest temperatures.

3.   When will my heat pump use auxiliary heat?

Generally, this occurs when the outside temperature is getting to the point of or below freezing combined with your indoor temperature being 3 or more degrees below the thermostat setting.  If the temperature is above 35 degrees and aux mode is staying on, you should call your favorite Missoula heating contractor to come to check on your system. 

4.   How long should auxiliary heat run?

Aux heat kicks on when your heat pump is struggling to keep the indoor temperature at the desired temperature.  If it comes on when the indoor temperature is 3 degrees below the set thermostat temperature, t will stay on until it has helped the heat pump “catch up.”  This usually takes up to about 2 hours.

5.   How do I stop my auxiliary heat from coming on?

In order to prevent aux heat from coming on, you need to prevent the temperature inside the home from dropping quickly.  This can be done by ensuring the home is insulated well and ensuring there are no holes or gaps where heat can escape. You can also shut doors to room not in use.  Another option to consider is using a space heater. Be cautious with this option because an electric space heater may be just as expensive as electric heat strips. 

6.   Is auxiliary heat more expensive than the heat pump running on its own?

If your heat pump uses electronic heat strips for its emergency and auxiliary heat needs, you WILL notice its use when your electric bill arrives.  Electronic heat strips source heat from electricity instead of outside air, which will consume MUCH more energy than your heat pump.   

If you use a gas furnace for your heat pump’s extra needs, it is most often more efficient than a heat pump in temperatures colder than 20 degrees Fahrenheit.

7.   What if my aux heat is on, but there is no heat in my home?

If your aux heat is turned on, but there is no heat, you have a problem in the system.  It could just be a circuit breaker needs to be reset or that a coil needs to be replaced.  It is best to call in a Missoula heating contractor to inspect your system to ensure these complex systems are working properly. 

8.   What should I do if my heat pump auxiliary heat is always on?

If it seems like your aux heat is constantly on, you may want to get your HVAC system inspected by a Missoula heating professional.  Your heat pump may be getting old.  You may need to reinforce your insulation.  You may have an electrical problem.  It is best to have a certified technician come and determine your specific problem.

9.   How do I tell if my heat pump emergency heat is on?

You can tell if your emergency heat is on because a switch on your thermostat has been moved to emergency heat.  Some thermostats will have the words “emergency heat” lit up on the screen when it is turned on.  Most simply, you will know your emergency heat is turned on because somebody in your household turned it on.

10.   Is it bad if the auxiliary heat comes on?

It is not bad when auxiliary heat kicks on.  It is what the system was designed to do to keep your home comfortable.  If it stays on forever, you likely have a problem.  But there is no need to fret if your system has just gone into aux mode!

Explore Heat Pump Backup Options with Missoula Heating Contractors

By now, we’re hoping you understand the difference between emergency heat vs. auxiliary heat and know when you should call your favorite Missoula heating contractor to check on your system.  Give us a call at Garden City Plumbing and Heating to find out what heat pump would work best for your property and schedule your installation or upgrade today!