Efficient Heating and Cooling: A Six-Year Journey with Mini-Split Heat Pump System
Almost six years ago, we made a pivotal decision to install a mini-split heat pump system in our home. Since then, I’ve documented the highs and lows, shared the intricacies of how the mini-split system functions, and chronicled our personal experiences with it. Having recently sold our house as we prepare to relocate to North Carolina, I saw this as an opportune moment to offer a final review. This article will delve into the financial savings we’ve realized, the service issues we’ve encountered, and the overall performance of the system, especially in the demanding climate of Michigan.
Understanding Mini-Split Heat Pumps
Before diving into the specifics, let’s recap how a mini-split heat pump system operates. Unlike traditional HVAC systems, mini-splits require no ductwork. The system comprises an outdoor compressor unit and an indoor head unit responsible for both heating and cooling. This setup is advantageous for homes without existing duct systems or those looking to supplement their primary heating source.
In our case, even though we had a functional boiler, it would only kick in during extremely cold conditions or when we decided to shut off the mini-split. The primary reason for this was cost—our boiler runs on propane, a significantly more expensive fuel option compared to the electricity required for the mini-split.
Performance in Michigan’s Harsh Winters
Residing in the middle of Michigan means we face severe cold, especially during winter months. As I write this, it’s January with temperatures hovering around the low 20s Fahrenheit. Despite the biting cold, our mini-split has performed admirably. According to the manufacturer, our unit operates efficiently down to 15 degrees Fahrenheit. However, we found it functional even at temperatures as low as 9 degrees before it automatically shuts down, necessitating the boiler’s operation.
Although it’s possible to purchase units capable of working at temperatures as low as minus 15 degrees, we opted not to spend the extra money for such a feature. Instead, we found our existing setup satisfactory, except for the occasional reliance on the boiler during the harshest winter days.
Design Considerations and Comfort
Our home is a long, narrow structure, allowing the mini-split to blow air down the hallway. Consequently, there is a slight temperature discrepancy between the living room and the bedrooms, typically around 4 to 5 degrees. This minimal difference hasn’t posed any significant discomfort, primarily owing to our home’s airtight and energy-efficient design.
Choosing the Right Unit for Your Home
One of the most common questions I receive is: "How many mini-split units do I need for my 2,000 square foot house, and what size should they be?" The truth is, this isn’t a one-size-fits-all answer. Several variables need to be assessed, such as the type of windows, air tightness of the house, wall and attic insulation, the home’s orientation, and most importantly, the climate zone.
For instance, after consulting with a qualified HVAC contractor, we calculated our heating and cooling needs to be around 20,000 BTUs. We then opted for a 19,500 BTU unit, which has efficiently met our requirements. It’s crucial to engage a professional HVAC contractor for these calculations to ensure optimal performance and efficiency of the system.
Financial Savings Over Six Years
Now, let’s tackle the most compelling aspect: cost savings. When juxtaposed against the running costs of our propane boiler, the mini-split system has been a financial revelation. If we shut off the mini-split and relied solely on our boiler, it would consume about 12 dollars per month in electricity for its pump system and around 650 gallons of propane during the heating season. In total, this would amount to approximately $1,300 per heating season.
On the other hand, operating the mini-split resulted in an average cost of just $57 per month. Over an entire heating season, this equates to a mere $342. Over the tenure of six years, this has culminated in substantial savings of $5,748.
Considering our initial investment for the mini-split system was $4,100, we’ve not only recouped the cost but also saved an additional $1,648. These savings have enabled us to redirect our funds towards other household expenses, thus enhancing our overall financial well-being.
Service Issues and Maintenance
No system is devoid of maintenance and occasional hiccups, and our mini-split was no exception. Here are the two primary service issues we faced:
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Indoor Coil Icing Due to Coolant Leak:
Early in our usage, the indoor coil began icing up, leading to water dripping inside the house. After investigation, it was identified as a manufacturer’s defect involving a refrigerant leak. The company sent a replacement coil, and our technician installed it, recharged the system, and got it working perfectly again—all covered under warranty. - Dirty Replacement Coil:
After the coil was replaced, it started dripping water again, presumably due to manufacturing oil residues or dirt. The technician cleaned it using a foaming coil cleaner, which resolved the issue. While this service call did cost $85, it’s something homeowners could potentially do themselves.
For those wary of disassembling components to access the coils, it is advisable to seek a professional. However, for the DIY enthusiasts, there are various coil cleaning products available in the market.
Final Thoughts and Recommendations
Living in Michigan with its unforgiving winters has been an excellent testing ground for the mini-split heat pump system. After six years, here are my key takeaways:
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Performance: The mini-split has performed reliably down to temperatures well below its rated capacity, providing consistent heating and cooling in our energy-efficient home.
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Cost Savings: Our switch from a propane boiler to a mini-split has led to significant financial savings, making the initial investment more than worthwhile.
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Maintenance: While there have been minor service issues, most were covered under warranty or relatively inexpensive to resolve. Regular maintenance, such as cleaning the coils, can prevent some of these problems.
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Comfort: Despite a minor temperature variance between rooms, the overall comfort provided by the mini-split system has been satisfactory.
- Customization: Engaging a qualified HVAC contractor for a customized solution is crucial, as several factors influence the size and number of units required.
Conclusion
As we prepare to move to North Carolina, where the climate is considerably milder, our experience with the mini-split heat pump system in Michigan leaves us confident in recommending this technology to other homeowners. The financial savings, efficiency, and overall comfort provided by the system make it an excellent choice for those looking to modernize their heating and cooling without the need for extensive ductwork.
Hopefully, this comprehensive review addresses any questions you have about running a mini-split system in colder climates. If you have further inquiries or wish to share your experiences with mini-splits, feel free to leave a comment or reach out through our channel. Don’t forget to subscribe for more updates and insights as we embark on new adventures in our next home.
Thank you for joining us on this six-year journey—it’s been both educational and rewarding, reaffirming our belief in the potential of mini-split heat pumps for efficient, cost-effective home climate control.