Mitsubishi Diamond Contractor | Greater Portland, Maine
Heat Pump Installation
Built for Maine Winters
Whisper-quiet comfort in every room, every season. Zone-by-zone control, cleaner air, and year-round heating and cooling from a single system. Rebates up to $9,000 available.
- Zone-by-zone comfort control for every room
- Efficient down to -13°F, year-round heating and cooling
- Built-in air filtration for cleaner indoor air
- Rebates up to $9,000 through Efficiency Maine
- Mitsubishi Diamond Contractor, 12-year parts warranty
Up to $9,000
in Efficiency Maine rebates available for heat pump installation
Get a Free Heat Pump Quote
We call within 1 business day
By the Numbers
Why Heat Pumps Make Sense in Maine
-13°F
Minimum Operating Temperature
3x
More Efficient Than Electric Resistance
$9,000
Max Efficiency Maine Rebate
12 yr
Parts Warranty (Diamond Contractor)
$1,150
Heat Pump Water Heater Rebate
1 day
Typical Installation Time
The Process
From Assessment to Installation
We make the whole process simple, transparent, and stress-free.
1
Free Home Assessment
We evaluate your home's layout, insulation levels, and heating needs to design the right system: right-sized, right-priced.
2
Custom System Design
We specify the exact Mitsubishi units for your home, calculate your rebate eligibility, and provide a detailed written quote.
3
Professional Installation
Our certified crew installs your system in one day. We handle all Efficiency Maine paperwork and deduct your rebate upfront.
Customer Reviews
What Our Heat Pump Customers Say
"Our heat pump has been running all winter, even during the cold snaps, and our heating bill is down 40%. The installation crew was professional and done in one day. Horizon handled all the Efficiency Maine paperwork."
TM
Tom M., PortlandVerified Google Review
"I was skeptical about heat pumps in Maine winters. Horizon walked me through the data, showed me real performance numbers, and now I'm a believer. The system is incredibly quiet and the house is comfortable in every room."
LB
Lisa B., ScarboroughVerified Google Review
"We got three quotes. Horizon was the most thorough by far. They actually measured our rooms and explained exactly why they were recommending the units they did. The rebate came off our invoice immediately. Couldn't be happier."
RK
Rob K., WestbrookVerified Google Review
Common Questions
Heat Pump FAQs
Yes. Modern cold-climate heat pumps like Mitsubishi's Hyper Heat series operate efficiently down to -13°F. Maine winters are well within their operating range, and our data from hundreds of Maine installations confirms they perform reliably year-round. For a detailed look at cold-weather performance data, see our guide: Cold-Climate Heat Pump Performance Data.
Efficiency Maine rebates for heat pumps are $1,000 to $3,000 per outdoor unit depending on your income level, up to $9,000 for qualifying households. We're a registered vendor and handle all the paperwork. We deduct your rebate from your invoice before you pay, so you never have to wait for a check. See the full breakdown of income tiers and current amounts on our Efficiency Maine rebates page.
Yes. Through December 31, 2026, Efficiency Maine is offering an additional $500 per housing unit for eligible whole-home heat pump upgrades. This bonus stacks on top of the standard $1,000–$3,000 per unit rebates. The total for a qualifying whole-home system can reach $9,500 or more depending on your income tier. We verify your eligibility and apply all rebates directly to your invoice. See the current rebate amounts for full details.
Yes. Efficiency Maine's Green Bank offers financing starting at 0% APR for 1-year bridge loans and 5.99% for 5-year terms. NEIF Energy Plus offers up to $50,000 at 9.99% APR for homeowners combining a heat pump with other improvements. Both programs are unsecured: no lien on your home, no prepayment penalties. We walk through your financing options at the free assessment. See our 0% heat pump financing and rebates page for current loan terms and how to apply.
Mitsubishi's Diamond Contractor designation is their highest tier. It requires rigorous training, ongoing certification, and a track record of quality installations. As a Diamond Contractor, we can offer an extended 12-year parts warranty, compared to the standard 5-year warranty with other installers. For more on our certifications and what sets our installations apart, see our frequently asked questions.
Most single-zone installations are completed in one day. Multi-zone systems (3-5 units) typically take 1-2 days. We'll give you a specific timeline when we provide your quote.
In most cases, yes. A well-insulated home requires a smaller (less expensive) heat pump system and will see much better energy savings. Learn more: Is Your Heating System the Right Size for Your Home?. We offer insulation and air sealing alongside heat pump installation, and our free assessment evaluates both your insulation and heating needs together so we can recommend the right sequence of improvements for your budget. See our full cost breakdown in the heat pump cost guide for Maine homeowners, or compare systems in our guide to Maine energy efficient heating options.
Town-Specific Pages
Heat Pump Installation by Town
Detailed local pages for towns with specific housing types and permitting considerations:
Heat Pump Installation Throughout Greater Portland
Horizon Homes installs cold-climate heat pumps across Greater Portland and Southern Maine, including: