Furnace & heating
AC repair
Heat pumps
Ductless mini splits
Carrier
Trane
GoodmanSeasonal tune-up and full diagnostic on your Carrier, Trane, or Goodman system - readings shown to you before any repair is proposed
Diagnosis first, numbers second - you approve the repair price before a single part goes in.
Get your free estimateFast, Reliable AC Installation Across Los Altos
Most full AC installations in Los Altos run between $3,500 and $7,500, depending on the system size and what your home’s existing ductwork and electrical panel can handle. We serve Los Altos daily, with crews that know the difference between a 1960s ranch on a flat lot and a hillside split-level near the foothills. You’ll get a written price before any work starts, and you’ll talk to a live person when you call (669) 800-4179, day or night.
Los Altos is a specific place. The homes are older, the lots are large, and the expectations are high. That’s why we treat AC Installation as a house-by-house job, not a box-swap. Whether you’re retrofitting central air into a home that never had it or replacing a system that’s been struggling through August, our team plans the work around your ducts, your panel, your HOA, and your schedule.
Why Cold Harbour Heating and Air San Jose Is Los Altos’s Preferred AC Installation Company
Los Altos homeowners tend to ask harder questions than most, and they should. There’s a lot of HVAC work in this town that doesn’t hold up: undersized equipment slapped in without a load calculation, condensers planted wherever the truck could reach, crawlspace ducts left leaking. We’ve been called out to fix all of it. Victor Mancini, who leads our team, insists on walking the crawlspace and the panel before quoting a new system. That’s the only way to know whether a 1950s ranch can actually support the equipment you’re paying for.
Our reputation in Los Altos is built on showing up in the window we gave and leaving the job site cleaner than we found it. Those are two of the five values in The Kingswell Way: say the price before the work, show up in the window, leave the place clean, put the guarantee in writing, and come back if it fails. Every installation gets a written price handed over before a single tool comes out. Every repair gets a 365-day written guarantee. If it fails inside that year, we return and make it right at no charge.
We’re an independently owned and operated member of the Kingswell network, founded in 2003. Scheduling and dispatch are coordinated from our San Francisco Bay Area office, and the crews that work in Los Altos know the city’s housing stock. They know how to run line sets through a crawlspace without disturbing a rose garden, and they know what the Los Altos Hills border means for equipment noise.
Styles & brands we work with







Ductless Mini Split Installation in Los Altos
Ductless Mini Split Installation in Los Altos is the most practical answer for homes with no usable ductwork, rooms that never reach temperature, or architectural review boards that frown on visible rooftop equipment. Most ductless mini split installations in Los Altos run $3,500 to $7,500, depending on the number of indoor heads and the length of the line set. The outdoor unit is small enough to tuck behind a fence line, and the indoor heads mount high on a wall with only a three-inch hole to the outside.
What makes Los Altos different is the housing stock. A lot of the 1950s and 1960s ranches here were built with radiant heat only, or with gravity furnaces that never had air conditioning. Running new ductwork through those homes means cutting into walls and ceilings that haven’t been touched in sixty years, and a lot of homeowners don’t want that. A ductless system gives you real air conditioning without the carpentry.
When a ductless system makes sense
We recommend ductless when you’re adding AC to a specific part of the house, not the whole footprint. A bedroom over the garage that bakes all afternoon, or a converted patio room that always ran ten degrees hotter than the rest of the house. The system sizes itself to that room’s load, and you’re not paying to condition air for empty space.
What the install involves
The outdoor condenser sits on a pad or bracket near the wall you choose, the line set runs through a small hole to the indoor head, and the whole thing ties into a dedicated circuit. We use a cover to keep the line set tidy against the exterior wall. The work typically takes one day for a single-zone system, two days for a multi-zone job with long line runs.
AC Replacement in Los Altos
AC Replacement in Los Altos usually means pulling out equipment that’s fifteen to twenty-five years old and putting in a SEER2-rated system sized for the actual load of the house. A full central AC replacement here runs $3,500 to $7,500, with the final number depending on system tonnage, duct condition, and whether your electrical panel can carry the new equipment. The biggest mistake we see is replacing a unit without checking whether the ducts can move the air the new system needs.
Los Altos has a lot of homes where the original furnace still sits in the hall closet, and someone added a condenser in the 1990s without touching the ducts. The result is a system that cools unevenly and runs constantly. Replacing just the condenser in that situation doesn’t fix the airflow problem. A proper replacement starts with a Manual J load calculation and a hard look at the duct runs.
When to replace instead of repair
If your existing AC uses R-22 refrigerant, replacement is usually the better move. R-22 has been phased out, and the remaining supply is expensive enough that a refrigerant recharge often makes no sense. Add that to a compressor nearing the end of its life, and you’re spending repair money on a system you’ll replace within three years anyway.
What goes into the quote
Our written quote includes the equipment, the line set, the electrical work, the permit, and the labor. It does not change when the crew arrives. We calculate the system size from the home’s square footage, window orientation, and insulation, not from the size of the old unit. Sizing to the old unit is how you end up with a system that short-cycles and leaves cold spots upstairs.
Trusted Brands We Service in Los Altos
Our technicians are trained to service nine major residential HVAC brands, and in Los Altos we work most frequently with Trane, Lennox, and Goodman equipment. That matters here for two reasons. First, a lot of Los Altos homes have mixed systems: a newer condenser outside, an older air handler inside, maybe a Rheem furnace from a previous decade. The crew needs to know how those pieces talk to each other. Second, our local parts access means we can turn around a replacement quickly when you’re without cooling during a heat wave. You don’t have to wait on a backordered part from another region.
Common AC Installation Problems We See in Los Altos Homes
- Original undersized ductwork in 1950s to 1970s ranch homes. The furnace was sized for heat only, and the ducts were never meant to carry the volume a modern AC needs. We regularly find low-velocity runs that move less than half the air the new system requires.
- 100-amp electrical panels that can’t support a heat pump. Los Altos homes from this era often still have the original service panel. A modern SEER2-rated heat pump or central AC usually needs 200-amp service, and we handle that panel swap as part of the install.
- Asbestos-wrapped ducts in older crawlspaces. Homes built before 1975 frequently have asbestos tape or wrap on the duct seams. We don’t cut into that blind. We test, follow abatement protocol, and in most cases recommend replacing the duct run rather than disturbing it.
- HOA rejections after the equipment is ordered. The Los Altos boards with strict architectural review want to approve the condenser location, the screen, and the noise level before the unit goes in. We’ve seen replacements get rescheduled because nobody asked first.
See the difference
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After
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After
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AfterPricing for AC Installation in Los Altos, CA
Here’s the honest picture for Los Altos. A straightforward AC replacement on a home with good ducts and a modern panel lands around $3,500 to $5,500 for a 3-ton system. A full install with duct retrofit, panel upgrade, and a higher-efficiency heat pump runs toward $7,500 or a bit more. Ductless mini splits in Los Altos fall in the same $3,500 to $7,500 range depending on the number of zones.
| Service | Los Altos Price Range |
|---|---|
| AC Replacement | $3,500 – $7,500 |
| Ductless Mini Split Installation | $3,500 – $7,500 |
| Tune-Up | $80 – $200 |
The number that matters is the one on your written quote, and that quote is free. Call (669) 800-4179 and we’ll send a technician to your Los Altos home to walk the site, run the load calculation, and hand you a price before any work begins.
The Los Altos HOA Reality: Approval Before Equipment
If your Los Altos home falls under an HOA with architectural review, the sequence matters as much as the equipment. Boards in this city want to see the proposed condenser location, the noise rating of the unit, and often a screen enclosure that matches the home’s exterior. They meet on their schedule, not the install crew’s. That’s why we tell Los Altos homeowners to get the approval moving before you pick an install date, not after the unit is sitting in the driveway.
Noise is the biggest rejection trigger. Los Altos has specific noise limits, and a conventional condenser placed too close to a neighbor’s patio window will draw a complaint. The fix is usually a quieter unit (many of the newer Trane and Lennox models run below 60 decibels), a different location, or an approved enclosure. We can prepare the submittal documents, including equipment specs and proposed location photos, so the board has what it needs the first time.
Also, the city is particular about the location of the outdoor unit for newer high-efficiency systems, especially when the home sits on a corner lot or a hillside. That’s where Los Altos quiet-street expectations collide with mechanical reality. A good contractor plans for the review process. We do it every week here.
Why the Ducts and Panel Matter as Much as the Condenser
Here’s the thing someone working in a newer city wouldn’t run into: in Los Altos, many 1950s to 1970s ranch homes have original undersized ductwork and 100-amp panels. So AC installation often means a simultaneous duct retrofit and electrical service upgrade, because a modern SEER2-rated heat pump won’t run on a panel that old and won’t cool through ducts that small. Skip either one and you get a system that trips breakers in July and leaves the back bedrooms warm by dinnertime.
On a silent late-spring morning in the North Los Altos neighborhood, our crew replaced a 1972 Rheem furnace and added a 3-ton Carrier heat pump, but first we ran a load calculation that confirmed the original low-velocity ducts could not move enough air. So we discreetly retrofitted the crawlspace with new insulated ducting, swapped in a 200-amp panel, and set the blower motor to match the existing static pressure, all before lunch. That’s the kind of job that separates a heat pump that works from one that looks good on paper.
Homes built before 1975 in Los Altos also have asbestos-wrapped ducts in many crawlspaces. You can’t just pull those out. We test the wrap, follow abatement protocol, and more often than not recommend replacing the duct run entirely rather than disturbing the original material above your hardwood floors. It costs more up front, but it avoids a bigger problem later.
We Also Serve Cities Near Los Altos
Our crews cover Los Altos and the surrounding peninsula communities, including Mountain View, Stanford, Palo Alto, and Menlo Park. The same written pricing, the same 365-day guarantee, and the same live-person phone coverage apply wherever the job is.
Serving Los Altos, CA - Our Local Coverage Area
We’re based in the Los Altos area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About AC Installation in Los Altos
Yes, if your Los Altos home is in an HOA with architectural review, you’ll typically need the board to approve the condenser location, noise rating, and any screen enclosure before the install. Start the approval process early, because boards here meet on a fixed schedule and will not rush a decision for your install date. We prepare the equipment specs and location photos for your submittal. Call (669) 800-4179 and we’ll help you get it right the first time.
Choose a quieter unit (many modern models run below 60 decibels), place the condenser away from your neighbor’s patio or bedroom windows, and if the HOA requires it, add an approved screen enclosure. Los Altos homeowners are sensitive to mechanical noise, and a complaint to the board can force a relocation after the fact. We’ll help you pick a location that meets the noise limit and the HOA’s requirements.
Most likely, yes. Homes from the 1950s through 1970s in Los Altos often still have a 100-amp panel, and a modern SEER2-rated heat pump or central AC usually needs 200-amp service. We include the panel swap in the written quote when it’s required, so there’s no surprise when the crew arrives. Call (669) 800-4179 and we’ll check your panel as part of the free estimate.
The short answer is: don’t cut into them blind, and in many Los Altos homes from before 1975, replacement makes more sense than cleaning or patching. We test the wrap, follow strict abatement protocol, and recommend replacing the duct run with new insulated ducting rather than disturbing the original material. It moves more air, and it’s safer. The cost is included in your written quote up front.
Yes. Ductless mini splits in Los Altos often get approved more easily than central systems because the outdoor unit is small and can be placed discreetly, and the indoor head only needs a three-inch wall penetration. We position the equipment where the board will approve it and provide the specs for the submittal. Call (669) 800-4179 for a free estimate that includes the approval paperwork support.
Written by Victor Mancini, Owner at Cold Harbour Heating and Air San Jose, serving Los Altos since 2003.