Missoula HVAC Contractors: Ground Source vs Air Source Heat Pumps

Heat pumps are an incredible technology that has come a long way to be one of the most eco-friendly heat sources for Missoula homeowners.  Late-model heat pumps can keep a home warm in single-digit degrees and even into negative Fahrenheit temperatures. Let’s take a look at comparing ground-source to air-source heat pumps and see what would be a great fit for your home.

What is An Air Source Heat Pump?

An air-source heat pump will provide comfortable temperatures year-round. This unit works by pulling heat out of the air and sending it either into or out of a house. In the summer, it pulls heat from the indoors and sends it to the outside. In the winter, it pulls heat out of the outside air and brings it into your home. 

There is a unit that goes inside the home, in the basement or utility closet, as well as an outdoor unit that sits near the home. These units have become incredibly efficient and have emergency systems in case they cannot maintain the desired temperature. Missoula HVAC contractors have installed heat pumps in Western Montana homes and have seen many customers enjoy the year-round benefits of this system. 

What is a Ground Source Heat Pump?

Ground-source heat pumps are similar to air-source heat pumps in that they provide comfort year-round by moving heat from one place to another. Ground source heat pumps use a series of tubes buried in the ground near the home to collect heat, which is then sent into the home. In the summer, heat is pulled from the indoor air and dissipated through the tubes into the ground.  It is important to clarify that ground-source heat pumps are not the same as a geothermal heat source.  

Interestingly, geothermal heat makes use of heat generated from the earth, while ground source heat pumps make use of heat from the sun, absorbed into the top layers of the ground.  A home using geothermal heat must be near a geothermal plant, while a ground source heat pump will use tubes buried at the property. Missoula HVAC contractors bury a series of tubes in the yard of a Missoula home, which means that apartments, condominiums, and homes with very small yards cannot make use of this type of heat.

20 Questions: Ground Source VS Air Source Heat Pumps

As we play our fun version of 20 questions, we’ll determine whether air-source or ground-source heat pumps will come out on top. Let’s jump in!

1. Is a ground source or air source heat pump cheaper to install with Missoula HVAC contractors?

Air-source heat pumps have a lower up-front cost of installation.  This is mostly due to the simplicity of installing an indoor unit and an outdoor unit compared to the cost of manual labor in digging up the yard to install the tubing along with the indoor unit. 

2. Is air source or ground source less work to retrofit in a home with forced air central heat?

Undeniably, air-source is less work to retrofit in a home with forced air heat.  As long as the ductwork is in good condition, an air source heat pump can be retrofitted fairly simply. A ground source heat pump can replace the indoor unit fairly simply but will still require burying the tubing in the yard, which can be a large undertaking.

3. Which requires less work to retrofit in a home with radiant heat?

Both air-source and ground-source heat pumps can be used with a radiant heat system.  Air-source will be simpler than ground-source because it requires Missoula HVAC contractors to install the indoor and outdoor unit, while ground-source requires burying the tubes in the ground.

4. Which type of heat pump requires less space to install?

Air-source heat pumps can be installed with relatively little sacrifice to space inside or outside your property. While both units require the same amount of space inside the home, ground-source heat pumps require yard space outside the home. 

5. Is a ground source or air source heat pump cheaper to repair?

Air-source heat pumps are typically less costly to repair than ground-source heat pumps.

6. Which type of heat pump requires less work to maintain?

Both types of heat pumps require yearly servicing by a licensed Missoula HVAC contractor.  Beyond this, you will need to replace filters regularly.  The maintenance is pretty similar, so we will call this one a tie.

7. Does an air source or ground source heat pump have a cheaper average cost for a single repair?

Average repairs are actually about the same, ranging from a few hundred to about $1,500.  Most repairs need to be done on the unit in the home, which ends up being comparable. This question will be a tie.

8. Which is Less Work to Repair, a Ground Source or Air Source Heat Pump?

According to Missoula HVAC contractors, common repairs for both types of heat pumps include recharging the refrigerant, dirty coils, fan speed, etc. The indoor unit is the most likely part of the system to need repairing.  On this front, this question is a tie. If there is a problem with the outdoor portion of a heat pump, the air source is likely to be cheaper.  Because the air source heat pump outdoor unit is readily accessible, repairs can be pretty quick. Because ground source heat pumps have an underground system, getting to the source of the problem can be complex, making outdoor repairs more work. For the outdoor portion of the heat pump, air source systems are less work to repair.

9. Is a ground-source or air-source heat pump more efficient to run in the winter?

While air-source heat pumps reduce in efficiency when the outside temperature becomes extremely cold, ground-source heat pumps make use of the near-constant temperature of the earth, around 55 degrees Fahrenheit. So even when the outside temperatures are at 20 degrees Fahrenheit, ground source heat pumps are just as efficient as when it is 50 degrees outside. Ground source heat pumps get this point.

10. Which type of heat pump is more efficient to run in the summer?

Ground-source heat pumps are more efficient in the summer as well. The ground’s near-constant temperature of around 55 degrees makes for efficient work to produce cool air to pump into a house.  Air source heat pumps work differently in the summer by pulling heat out of the home and pumping it outside.  Regardless of function, ground source heat pumps get this point.

11. Which is cheaper to run, an air-source heat pump or a ground ground-source heat pump?

Ground-source heat pumps are cheaper to run!  Because ground-source heat pumps are more efficient in both summer and winter at bringing a home to a desired temperature, it gets this point.

12. Which is more friendly to the environment, air source or ground source heat pumps?

While there is a consideration to be made concerning the digging up of the ground, the reality is that the ground settles around the tubing, and the grass grows back. In the end, both units use a refrigerant, and both units end up in a landfill after a few decades.  When it really comes down to it, in the long run, this question is a tie.

13. Which system has a longer life expectancy of its outdoor components?

The tubing of a ground-source heat pump should last about 50 years.  The outdoor unit of an air-source heat pump should last about 10 to 15 years.  This question goes to ground source heat pumps by a landslide.

14. Which indoor unit has a longer life expectancy, according to Missoula HVAC contractors?

The indoor unit of a ground-source heat pump is designed to last about 25 years.  On the other hand, the indoor unit of an air-source heat pump can be expected to last about 15 years.  Ground-source heat pumps win this point.

15. Which system will best be able to keep my Missoula home at my desired temperature?

Late-model heat pumps come with auxiliary heat, often in the form of heat strips to be used when the heat pump becomes too inefficient to keep up with the heat demand.  These generate heat through electricity, a notoriously inefficient heat source. While air-source heat pumps lean on these as the outside temperatures get extremely cold, ground-source heat pumps do not typically need these.  Both ground-source and air-source heat pumps are designed to maintain a certain temperature, but ground-source is able to do it more effectively. Ground source heat pumps get this point.

16. Which system works better alongside a secondary heat source?

Whether you are considering a mini split in your garage or radiant in-floor heating in your bathrooms, your answer may differ. A mini-split will not have any impact on the heat pump running in your home. If you want to have radiant in-floor heat in some portion of your home, you may consider having your heat pump heat through radiant heat throughout your home instead of forced air.  This will not necessarily be impacted by the source of heat on your heat pump.  Both ground and air-source heat pumps can be installed to work with a secondary heat source.  As such, this question is a tie.

17. Which unit is more common in the US, ground-source or air-source heat pumps?

Due to the lower cost and simpler installation, air-source heat pumps are more common in the US.

18. Is a ground source or air source heat pump more common in Montana?

While air-source heat pumps have been getting more efficient at low temperatures, ground-source heat pumps have built a reputation in Montana for reliable heat.  Because of the cold Montana winters, ground-source heat pumps have been more common than air-source heat pumps.  As air source heat pump technology develops, they are growing in popularity.  Missoula HVAC contractor will give this one to ground source heat pumps.

19. Which has a more efficient seasonal coefficient performance?

Ground-source heat pumps can be between 3 and 5 during the winter months. Air source heat pumps range between 2 and 4 during the winter months. This can vary depending on the season and region, but overall, ground-source heat pumps tend to be 10 to 25% more efficient than air-source heat pumps. Ground source heat pumps get this point.

20. Which will be better for my Missoula home?

There are many factors as to which type of heat pump would work better for your Missoula home.  You will want to consider your property size, what you have available for up-front costs, what you hope to spend monthly on energy costs, and whether you want a secondary type of heat and what kind.  There is no simple answer to this question, so we will call this one a tie.

And the Results Are In!

Our friendly game of 20 questions yielded some fun results.  Comparing two types of heat pumps that function similarly inside the home but very different outside the home can be tricky. Finding the right questions to highlight the similarities and differences is no simple task. Nonetheless, here is our final tally:

Air source heat pumps got 7 points.

Ground source heat pumps got 8 points.

Five questions resulted in a tie.  

Missoula HVAC Contractors Are Ready to Take the Call

If you are looking for more information or are ready to schedule an installation, Garden City Plumbing and Heating is ready to be of service!  Call us at (406) 728-5550 or contact us online today!