Mini split installation in Hillsborough, CA covers system design, zoning, and meticulous outdoor and indoor unit placement to preserve curb appeal while delivering quiet, energy-efficient comfort. Our process includes load calculations, equipment selection, code-compliant mounting, refrigerant handling, commissioning, and customer training, taking into account permitting and HOA considerations. Ongoing maintenance, warranties, and performance testing ensure long-term reliability in Hillsborough's coastal climate. Properly sized installations offer predictable comfort, reduced energy use, and corrosion-resistant operation for Hillsborough homes. Our professional guidance helps homeowners maximize value.

Schedule My Service

(650) 605 – 5986

Mini Split Installation in Hillsborough, CA

Choosing the right mini split installation in Hillsborough, CA means balancing comfort, efficiency, and preservation of your home’s appearance. Mini split systems provide zone-based heating and cooling with minimal ductwork and low visual impact, making them a smart choice for Hillsborough homes where energy efficiency, quiet operation, and aesthetic sensitivity matter. This page explains the full installation process, common issues to avoid, code and permitting considerations in Hillsborough, and the long-term maintenance and warranty options you should expect.

Why a mini split is a good fit for Hillsborough homes

Hillsborough has a mild Mediterranean climate with cool mornings and moderate summers. Mini splits work efficiently in these temperature ranges, offering precise temperature control and lower operating costs compared with older electric resistance or window unit solutions.
Many Hillsborough residences are older or architecturally sensitive. Mini splits require minimal interior disruption and can be installed with discreet indoor heads and careful outdoor unit placement to preserve curb appeal.
Zoned comfort means you only condition occupied rooms. For larger Hillsborough properties with bedrooms, offices, or sunrooms used intermittently, zone control improves comfort and reduces energy use.

Common mini split installation issues in Hillsborough, CA

Improper sizing and system design causing short cycling or inadequate comfort during occasional hot spells.
Poor outdoor unit placement leading to excess noise, reduced airflow, or increased exposure to coastal moisture and fog that can accelerate corrosion.
Inadequate refrigerant charge or poor brazing resulting in inefficient performance or leaks.
Insufficient insulation on refrigerant lines and condensate drains leading to sweating, energy loss, or water damage.
Aesthetic conflicts with homeowners associations or historic design elements when indoor heads or condensers are placed without consideration for sight lines.

What a professional mini split installation includes

The installation process for mini split systems in Hillsborough, CA should be thorough, code-compliant, and focused on long-term performance. Typical components of a quality installation:

Initial site assessment and system design

Load calculation specific to the room layouts, glazing, insulation levels, and local climate patterns of Hillsborough.
Zone planning to optimize comfort and efficiency. Multiple indoor heads may be specified for multi-zone systems to balance capacity and aesthetics.
Consideration of HOA or historic district restrictions when choosing locations for indoor heads and outdoor condensers.

Indoor and outdoor unit selection

Selection of single-zone or multi-zone heat pump systems based on load analysis.
Choosing units with appropriate SEER and HSPF ratings, inverter-driven compressors for part-load efficiency, and corrosion-resistant features for coastal fog exposure.
Matching indoor head styles (wall-mounted, low-profile ceiling cassette, ducted concealed) to room function and design priorities.

Professional mounting and structural prep

Secure mounting of indoor heads with vibration isolation and level installation.
Sturdy, elevated pad or wall brackets for outdoor unit placement to prevent pooling and limit exposure to moisture and debris.
Aesthetic routing of small-diameter refrigerant lines through neatly sealed chases or recessed channels when possible to preserve exterior appearance.

Refrigerant lineset, condensate, and electrical work

Precision brazing, leak detection, and refrigerant charging to manufacturer specifications.
Proper vacuuming and charge verification to ensure long-term reliability and efficiency.
Electrical wiring and disconnects sized to code, plus any necessary panel upgrades, breakers, and safety devices.
Condensate piping routed to approved drains or condensate pumps, insulated and slope-correct to prevent backups and staining.

Insulation and aesthetic placement

Insulating refrigerant lines and condensate drains to prevent sweating and heat gain.
Concealing linesets in paintable channels or within walls where feasible, while maintaining service access.
Using low-profile indoor heads, matching trim colors, and thoughtful condenser screening to comply with Hillsborough design expectations.

Commissioning and performance testing

Electrical verification, airflow measurement, superheat/subcool check, and balance testing.
Verification of heating and cooling capacity under typical Hillsborough seasonal conditions.
Noise level checks and vibration isolation confirmation for quiet operation in residential neighborhoods.

Customer walkthrough and operating instructions

Demonstration of system controls, scheduling, and zoning functions including app or remote operation when available.
Guidance on filter maintenance, recommended setpoints for efficiency, and seasonal operating tips relevant to Hillsborough weather patterns.
Documentation of installed equipment, schematic of system layout, and explanation of warranty coverage.

Permitting and code compliance

Pulling and managing local permits required by the Hillsborough building department, and ensuring compliance with California energy codes and appliance installation requirements.
Coordinating required inspections and documentation to meet local code and HOA guidelines.

Warranty and maintenance options

Expect manufacturer warranties on compressors and major components. Installer-provided labor warranties cover workmanship for a defined period.
Annual maintenance is recommended: clean or replace filters, inspect condensate drains, check refrigerant charge and electrical connections, and clean indoor and outdoor coils.
Seasonal checks before hot or cool seasons help prevent minor issues from becoming system failures and maintain efficiency in Hillsborough’s climate.

Performance, longevity, and energy considerations

Properly sized and installed mini splits deliver predictable comfort, lower energy use, and quieter operation than many alternatives.
In Hillsborough, systems that emphasize part-load efficiency and inverter technology perform well year-round and reduce greenhouse gas emissions relative to older electric or gas systems.
Thoughtful placement and corrosion-resistant components extend service life in local conditions where marine layer and humidity can influence equipment longevity.

A professional mini split installation in Hillsborough, CA focuses on careful design, discreet placement, reliable mechanical work, and compliance with local requirements. When installed and maintained correctly, mini split systems provide efficient, zoned comfort that respects both the appearance and the comfort needs of Hillsborough homes.

testimonials

hear what our satisfied clients have to say

5.0

We found Plum HVAC in 2024 after spending more than 2 months searching and comparing estimates. The owner Sam gave us a very competitive price for a Mitsubishi mini-split and the installation went off without a hitch. Our experience was so positive that we later requested their services twice more to also install A/Cs for our 2 other rooms. Their technician, Jake, led our installations each time and we were very impressed by their professionalism and quality of work. Now 1 year in and we could not be any happier, nor have we encountered any issues with our models.

Jesse Y.

5.0

Sam of Plum HVAC, responded to our Heat Pump installation request promptly and provided a very competitive estimate after an onsite visit. He was very flexible and patient to answer and explain our questions. After we signed the contract, he and his team of 4 worked very hard to deliver and install the whole Heat Pump system on time with good quality. I am particularly impressed by their problem solving skills to overcome different connection challenges for the attic installation. Each day before they started, they covered the floors with protection blankets and cleaned after they were done for the day. They also revised the drainage and electric work per the city inspection guidance. Sam and his team were professional and honest so we highly recommend Plum HVAC to any customers who need HVAC work done for their houses.

Chunshi C.

5.0

We needed to install a mini-split in a backyard unit. Sam and his team helped with this, and they did a fantastic job. Sam visited our place and clearly explained to me what needed to be done, and offered a great price. He scheduled the job for a few days later, and his team performed the job with extraordinary quality. Later, I noticed a minor issue and reached out to them. Sam helped me to fix the issue on a second visit by his team later in the week, providing top-notch customer service. I will work with them in the future for my HVAC jobs, and highly recommend them given their excellent work quality and customer service.

Majid J.

5.0

I reached out to 4 companies for mini split quotes; Plum HVAC pricing came in the lowest. Beyond that, Sam was very knowledgeable and kind during the in home consultation. He offered a quote in person, & stuck by it. They removed our old furnace, and installed a two head mini split in our two story townhouse. The work as you can see is very clean! The guys who installed it were very fun & professional. Sam & his team were communicative the whole way through including the permitting process. They took roughly one full day for install, which was very fast! Including removal & disposal of our old furnace. Natalie was very helpful throughout the Bayren Rebate process & always available for any questions! This system has changed our lives, wish we would have gotten it done sooner! It’s way better than we could have imagined.

Bobby R.

5.0

Plum HVAC exceeded my expectations in every way. Sam and his installer team were not only professional but also incredibly responsible throughout the entire process. They provided top-notch service at a very reasonable price, which is hard to come by these days. I highly recommend Plum HVAC to anyone looking for quality HVAC services. You won't be disappointed!

A Chui

5.0

I recently engaged Plum HVAC to install two mini-split units at my residence, and I'm thrilled with the outcome.Throughout the entire process, from the initial consultation to the project's completion, Plum HVAC showcased professionalism and expertise. The technician, Sam, arrived promptly and conducted a comprehensive assessment of my HVAC system. Sam took the time to thoroughly explain the technicians' tasks, the estimated duration of the project, and provided transparent pricing options.

Romero J.

5.0

Wonderful experience with Plum HVAC on a heat pump installation! I checked several companies, compared their recommendations, timelines, reputations and prices.Sam, the owner, was very professional and has almost 2 decades of experience in HVAC. When I asked dumb questions, he answered most graciously. And when I noted that some companies we queried said we could get away WITHOUT replacing our original ductwork from 1965, he gave us his honest opinion why that wasn't a good idea. (Hubby remembered later that people who worked in our attic adding insulation told us there were lots of duct leaks.)

Marlene S.

5.0

I called 8 different HVAC companies for quotes for a heat pump heating/ac system because I want to save money by switching from a forced air gas furnace to an electric heat pump system which will give me both heating and air conditioning. In addition my old furnace (circa 1991) was way oversized for my home and the air coming out too noisy. The New heat pump system is quieter and more efficient. Back to the quotes for the system, all the other 7 companies sent a salesperson/advisor to give the quote. Sam, the owner of Plum HVAC came our to give the quote. He was quick with his quote and was very knowledgeable. He didn't try to upsell me on anything and have the lowest quote of them all. His price was 60% less than the highest quote and 15% lower than the next second lowest quote.

Michael C.

5.0

Plum HVAC is an extremely professional, knowledgeable, and an established company to hire. I highly recommend Plum HVAC! Sam and his crew did a wonderful job. Sam worked with my schedule and his crew had completed the job with ease.

Blake

5.0

Sam was one of the most professional business owners I had the chance to meet over the past few years and I'm so happy I trusted him to install our new A/C unit.- He showed up on time- He was transparent (and reasonable) regarding pricing- He offered 2-3 options- His crew did a very clean/thorough jobWhat I loved the most though, was the fact he was very easy to communicate with. I would definitely use him again and recommend him to our neighbors/friends.

Bruno L.

5.0

We recently had a complicated Bryant Evolution dual fuel system with variable speed and zoning installed in our home by Plum HVAC, and we are very pleased! The team also changed the entire crawl space ducting, ensuring a comprehensive upgrade. The price was fair, and the team was always on time and easy to contact. Sam Mousavi, the head of the team, paid great attention to detail and demonstrated a strong understanding of systems. His expertise in HVAC systems and his friendly character made us feel comfortable throughout the process. We highly recommend Plum HVAC for their professionalism and excellent service.

Amirali B.

5.0

I cannot say enough about Plum HVAC, who replaced my aging heater furnace, and in particular Sam. Sam was very highly recommended by my sister, who replaced her furnace and added air conditioning.First, they gave me a good deal for a 2-stage, at the same cost as the lowest bid for a 1-stage. The other bids were dancing around some gas line work made by previous owners.

Kumar S.

Leave a Review

View All Reviews