Air Conditioning service in Hillsborough, CA, from Plum HVAC delivers comprehensive installation, repair, replacement, maintenance, and emergency response for large, multi-zone homes. Our team conducts thorough diagnostics, corrects sizing and airflow issues, upgrades filtration for wildfire smoke, and provides transparent estimates with documented warranties and rebates guidance. From load calculations and duct sealing to smart-thermostat integration and annual tune-ups, Plum HVAC emphasizes energy efficiency, indoor air quality, and long-term equipment life while minimizing disruption through timely scheduling. Our approach puts customers first.

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Air Conditioning Service in Hillsborough, CA

Keeping your home comfortable year-round in Hillsborough, CA means having an air conditioning system that runs efficiently, quietly, and reliably. Whether you own a historic estate or a modern residence, the full range of air conditioning services—installation, repair, replacement, maintenance, emergency response, and diagnostic evaluations—ensures peak performance, lower energy bills, and better indoor air quality. This page explains what those services include, common issues specific to Hillsborough homes, expected response and service procedures, and how warranty and rebate assistance and service agreements fit into long-term care.

Why specialized AC service matters in Hillsborough, CA

Hillsborough homes often feature larger footprints, multiple zones, and older ductwork. The Bay Area climate brings warm, dry summers with occasional heat spikes and seasonal wildfire smoke that raises demand for good filtration. Proper AC sizing, zoning, filtration upgrades, and routine maintenance are especially important to maintain comfort and protect home systems in this area.

Common air conditioning issues in Hillsborough, CA

Reduced cooling or uneven temperatures across rooms (common in multi-zone systems or homes with long duct runs)
Frequent cycling or short-cycling caused by improper sizing, dirty coils, or failing compressors
Weak airflow from ducts due to leaks, aging insulation, or blocked vents
Refrigerant leaks leading to poor performance and higher energy use
Strange noises (clanking, hissing, grinding) indicating loose components, blower motor issues, or failing bearings
Condensate drain clogs and water leaks that risk water damage in finished basements or utility areas
Thermostat or control failures, including incompatible smart-thermostat setups
Indoor air quality problems during wildfire events or high-pollen periods, necessitating upgraded filtration or air purification

Diagnostic and inspection process

A thorough diagnostic evaluation begins with a visual inspection and system history review. Typical steps:

Verify symptoms reported (no cooling, noises, smells, etc.)
Check electrical supply, breakers, and safety interlocks
Measure refrigerant pressures and temperature differentials across the evaporator coil
Assess airflow, blower motor operation, duct integrity, and filter condition
Inspect outdoor condenser, coil condition, and fan motor
Test thermostat and control wiring, including smart thermostat compatibility
Document findings, list prioritized repairs or upgrades, and provide a clear estimate

Diagnostics in Hillsborough often include an assessment of older ductwork, multi-zone dampers, and recommendations for better filtration given regional smoke events.

Repair, emergency service, and response times

Emergency symptoms include complete loss of cooling during heat spikes, refrigerant leaks, electrical burning smells, or water leaks causing immediate damage. Emergency service typically follows prioritized scheduling to address safety issues and prevent property damage.

Common repairs:

Refrigerant leak detection and repair with safe recover/recharge procedures
Compressor, capacitor, contactor, and motor replacement
Blower motor repair or replacement and belt/drive repairs
Condensate line clearing and drain pan repair
Thermostat replacement or reprogramming and control board repairs
Duct sealing and minor ductwork repairs

Typical response times vary with demand, but emergency issues are prioritized same day or within 24 hours where possible. Non-emergency diagnostics and standard repairs generally fall within set appointment windows; technicians arrive with diagnostic tools and common parts for efficient troubleshooting.

Installation and replacement: what to expect

Replacing or installing an AC system in Hillsborough should be a carefully planned project, not a rush decision. Key steps:

Load calculation (Manual J) to size equipment for actual cooling needs considering insulation, windows, occupancy, and multi-zone layouts
Equipment selection based on efficiency (SEER), noise ratings, and indoor air quality options
Ductwork evaluation and recommendations for sealing, insulation, or reconfiguration
Permit handling and code compliance checks
Professional removal and responsible disposal of old equipment
System startup, balancing, and performance verification with digital reporting

For large Hillsborough homes, multi-zone systems, variable-speed compressors, and advanced zoning controls are common upgrades to improve comfort and efficiency.

Maintenance and service agreements

Routine maintenance preserves efficiency and prolongs equipment life. Typical tune-up items:

Clean or replace air filters and advise on appropriate MERV ratings for wildfire smoke protection
Clean condenser and evaporator coils
Check refrigerant charge and inspect for leaks
Tighten electrical connections and test capacitors
Lubricate motors where applicable and inspect belts
Flush condensate drains and verify proper drainage
Test system performance and thermostat calibration

Service agreements often include scheduled seasonal inspections, priority scheduling, discounted labor or parts, and documentation of past services—helpful for long-term system tracking and resale value.

Warranty, rebate, and incentive assistance

New equipment typically includes manufacturer warranties for parts and compressors and a separate workmanship warranty for installation. Proper registration and professional installation can be necessary to maintain warranty coverage. For Hillsborough residents, there are often local utility rebates and state incentives for high-efficiency systems and heat-pump conversions. Assistance includes:

Explaining manufacturer warranty coverage and required maintenance steps
Guidance on paperwork and documentation needed to claim rebates or incentives
Verifying eligibility for regional energy-efficiency programs and helping submit applications when applicable

Indoor air quality upgrades and wildfire season considerations

Because Hillsborough can be affected by wildfire smoke, AC service often includes recommending higher-efficiency filters (MERV-rated), whole-home air cleaners, UV systems, and sealed return setups. These improve particulate removal and maintain indoor comfort alongside cooling.

How the quote and scheduling process works

A typical quote and scheduling process includes an intake to document symptoms or goals, an on-site diagnostic for accurate estimates, and a written scope that explains recommended work, parts, timelines, and warranty details. For installations, the estimate will include system sizing details, equipment options, permit requirements, and a projected timeline for completion and testing. Scheduling often offers coordinated windows to minimize disruption for Hillsborough homeowners.

Benefits of timely AC service in Hillsborough

Improved comfort during summer heat waves and more consistent temperatures across large homes
Lower energy bills through efficient operation and correct sizing
Reduced risk of emergency breakdowns during peak season
Better indoor air quality during smoke events and allergy seasons
Extended equipment life and preserved warranty coverage

Regular inspections, clear diagnostics, and informed replacement decisions keep Hillsborough homes comfortable and protected. Proper service balances system performance, energy efficiency, and long-term value while addressing local needs like multi-zone control and air quality.

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.

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