Los Altos HVAC Company handles residential and commercial heating-and-cooling repair, service, and installation across Los Altos and Santa Clara County. Whether something stopped working this morning or you are planning a system upgrade, we are open daily from 9:00 AM to 8:00 PM and ready to scope the job on the call before anything is scheduled.
Residential HVAC. Commercial HVAC. One number for both.
Call (650) 955-4592 for a quote.
From aging systems to brand-new installs, we cover the full range of heating-and-cooling work for homeowners, landlords, property managers, and commercial building operators. Repair, replacement, first-time installation, and seasonal maintenance all fall within scope, and work is carried out to code on every job.
When the air conditioner stops turning on, blows warm air, short cycles, or shows signs of a refrigerant leak, the first step is a thorough diagnosis before any parts are quoted. A visit covers compressor and condenser inspection, refrigerant leak check, airflow assessment, and coil condition. A frozen coil, for example, is usually a symptom of something else, and chasing the right cause saves time and money.
No heat in the house, a furnace making unusual noises, or a system blowing cold air all point to different problems with different fixes. A furnace visit covers the heat exchanger, ignition system, burner condition, and airflow path including the filter. Identifying the actual failure point before quoting the repair keeps the scope honest.
A heat pump that stops heating or cooling, or one that short cycles through both modes, often comes down to refrigerant charge, a reversing valve issue, or coil and compressor condition. We check all of it before settling on a repair path. We'll confirm the repair with you before it goes ahead.
At some point, repair costs more than replacement. If a system is older and has needed repeated attention, or if efficiency has dropped enough to show up in energy bills, a new-system quote makes sense. That quote covers a load calculation for the space, equipment selection based on the building's actual needs, and a clear breakdown of the installation scope.
Uneven temperatures from room to room, a system that runs constantly without reaching the set temperature, or a spike in energy bills can all trace back to leaking or poorly sealed ductwork. A ductwork visit covers inspection, leak detection, and sealing or repair where needed. Fixing the duct system often makes a bigger difference than adjusting the equipment.
A thermostat that reads the temperature wrong, fails to trigger the system, or simply needs replacing is a straightforward visit. We check compatibility with the existing system, handle the wiring, calibrate the new control, and test the system through a full cycle before leaving. Smart and programmable thermostats are a common upgrade for both homes and commercial spaces.
Airborne particulates, allergens, and general air quality concerns are increasingly common questions in this area. A visit covers an assessment of the existing filtration setup, a review of what the current air handler can support, and installation of a filtration system that fits the space. We'll get your comfort back on track.
A spring AC tune-up before Los Altos temperatures climb, and a fall furnace check before cooler weather arrives, are the two most practical investments in system reliability. A tune-up covers coil cleaning, refrigerant level check, electrical connection inspection, filter assessment, and a full system test. Scheduling before the season starts means shorter wait times and fewer surprises when the system is needed most.
When the heat or the AC quits, the situation does not wait for a convenient slot. A no-heat call in the middle of a cold night or a no-cool call during a Bay Area heat spike both get the same treatment: scope confirmed on the call, price discussed before anything is scheduled, and a clear picture of what the visit covers before the technician heads out.
We are open daily from 9:00 AM to 8:00 PM for emergency and short-notice calls. The system tested before the visit ends is the standard on every call, not just the urgent ones.
One call. One clear diagnosis. One price, agreed first.
The Bay Area's mild marine climate has historically meant that many homes here were built without central air conditioning. That picture is changing fast. Record heat events in recent years have pushed cooling from a luxury to a necessity, wildfire smoke seasons have made indoor air quality a real concern across Santa Clara County, and California's push toward electrification is moving more homeowners away from gas furnaces. These three services reflect what is actually coming up in Los Altos right now.
A large share of older Los Altos homes were built when cooling was not standard, and many do not have the ductwork to support a central AC system without significant renovation. Ductless mini-split systems are a practical answer: each indoor unit conditions the room it serves, the refrigerant lines run through a small wall penetration, and the existing structure stays largely intact. A first-time install quote covers a room-by-room load assessment, equipment selection, and a full breakdown of the installation scope so the price is clear before work begins.
Wildfire smoke events have become a recurring reality across Northern California, and Santa Clara County is not insulated from them. Standard residential filters are not built to catch the fine particulates that smoke carries into a home. Upgrading to MERV-13 or higher filtration addresses that gap, but higher-rated filters also create more resistance in the airflow path, which not every air handler handles well without adjustment. A visit covers a compatibility check on the existing system, filter upgrade installation, and an airflow assessment to make sure the system handles the added resistance without straining.
California's electrification direction and the Bay Area's mild winters make heat pump replacement a strong fit for Los Altos homes that are ready to move on from an aging gas furnace. Heat pumps handle both heating and cooling in a single system, and the region's relatively moderate cold means they operate efficiently here through most of the year. A quote covers load assessment, equipment selection across ducted and ductless options, installation, and a full system test before the visit closes.
Noticing uneven temperatures or a spike in energy bills? For property managers, landlords, and commercial building operators, HVAC problems carry a different weight than they do in a single-family home. A system down in a rental unit or a retail space needs a clear answer fast. We work with office buildings, multi-unit residential properties, and commercial spaces in and around Los Altos, and we keep the communication straightforward: clear notes on what was found and what was done go with every visit, so the person managing the property has a record of the work.
Call us and we'll handle the rest.
The hardest part of an HVAC problem is knowing when to call, and the second hardest is knowing what the call will cost. The answer is: ask on the phone. The diagnostic or service-call fee is explained when you call, before anything is scheduled. The price for the repair or installation is confirmed before work begins. What the visit covers is laid out up front so there is nothing to decode after the fact.
Common questions worth asking: whether the situation calls for a repair or a replacement quote, what a tune-up covers versus a diagnostic visit, and what the service-call fee includes. Those are fair questions and they get straight answers.
The visit ends with the system tested, not just the part swapped. That is how we confirm the repair actually solved the problem rather than guessing at it. We're one phone call from getting your comfort right.
We serve Los Altos and the communities around it throughout Santa Clara County, including Mountain View, Sunnyvale, Cupertino, Los Altos Hills, Palo Alto, Menlo Park, and Saratoga. Both residential and commercial properties throughout the area are within our service range. If you are unsure whether your address falls within reach, a quick call settles it.
A system that runs without cooling is one of the most common calls we get during warm stretches in Los Altos. The most frequent causes are a low refrigerant charge from a slow leak, a dirty or blocked condenser coil, or a compressor that is not operating at full capacity. The diagnostic visit covers all of those, and the repair is confirmed before any work proceeds.
A frozen coil is almost always a symptom of something else, not the problem itself. Restricted airflow from a clogged filter, a low refrigerant charge, or a blower issue can all cause the coil to ice over. The visit covers finding the underlying cause rather than just thawing the coil, because the ice will return if the root problem is not addressed.
Many Los Altos homes were built before central AC was standard, and not all of them have ductwork that can support a ducted system. If existing ducts are in good condition, a central AC installation may be the right path. If there are no ducts or the existing ductwork is undersized, a ductless mini-split system conditions individual rooms without requiring new duct runs, which avoids significant renovation work.
A mini-split installation involves placing an outdoor compressor unit, routing refrigerant line sets through a small wall penetration, and mounting the indoor air handler in the room being conditioned. The refrigerant charge is set to the manufacturer's specification during commissioning, and the system is tested through both heating and cooling modes before the visit ends. The location of the indoor unit matters for coverage and airflow, and that is part of the planning conversation before anything is ordered.
Standard one-inch residential filters are not rated to capture the fine particulate matter that wildfire smoke carries into homes. MERV-13 and higher filtration media addresses that gap, but higher-rated filters also restrict airflow more than standard ones. The visit covers a compatibility check on the existing air handler before the upgrade is installed, so the system can handle the added resistance without straining the blower or reducing airflow to the point where comfort is affected.
A heat pump replacement starts with an assessment of whether the existing structure and equipment support the transition, followed by a load calculation to size the new unit correctly. Heat pumps handle both heating and cooling from a single system, which means the installation replaces both the furnace and the air conditioner where both exist. The system is tested through heating and cooling modes before the visit closes.
A system that is working harder than it should to maintain temperature, often because of a refrigerant leak, a dirty coil, leaking ductwork, or a failing component, will draw more power without delivering proportionally more comfort. A diagnostic visit checks the system's operating efficiency alongside the mechanical condition, so the cause of the elevated energy use is identified rather than guessed at. Duct leaks in particular are a common contributor that does not show up as an obvious equipment failure.
A system that short cycles, struggles to reach the set temperature on warm days, makes sounds it did not make in previous seasons, or requires refrigerant more than once in a short period is showing signs of wear. Uneven cooling across rooms, a noticeable increase in energy bills, or visible ice on the refrigerant lines are also indicators worth addressing. Catching these early usually leaves more options on the table than waiting until the system stops working entirely.
A burning smell at startup, especially early in the heating season, can be dust burning off the heat exchanger and may clear on its own. A persistent burning smell, or one that appears during normal operation, points to an electrical or mechanical issue that needs a diagnostic visit. A musty smell typically indicates mold or mildew growth somewhere in the duct system or on the evaporator coil, and that is addressed through cleaning and, where appropriate, a UV air purifier installation.
No. Leave the system in its current state so the technician can observe how it is operating and run diagnostics with the system live. Shutting off power before the visit can make it harder to reproduce the symptom and may slow the diagnostic. If the power needs to be shut off for any part of the work, the technician will handle that as part of the visit.
Clear the area around the indoor unit or furnace, the outdoor condenser, and any supply or return registers the technician may need to access. That means moving storage, boxes, or furniture that blocks the equipment or the path to it. Good access to all three points, indoor unit, outdoor unit, and registers, lets the diagnostic and the repair proceed without delays.
We are open daily from 9:00 AM to 8:00 PM. Whether the system is down right now or you are planning ahead for a new install or seasonal tune-up, the process starts with a call.
Clear answers. Real pricing. Real fast response.
Call (650) 955-4592 to get a quote or schedule service. We'll get your comfort back on track.
Whether you are dealing with a system that stopped working this morning or planning a seasonal tune-up before temperatures shift, we cover the full range of residential and commercial heating-and-cooling work across Los Altos and Santa Clara County. The table below lays out what each service covers, who it fits best, and a practical note to help you decide where to start. Call us with any question and we will scope the job on the phone before anything is scheduled.
| Service Type | What It Covers | Common Needs | Things to Know |
|---|---|---|---|
| AC Repair & Service | Compressor and condenser inspection, Refrigerant leak check, Airflow and coil assessment, Diagnosis before any parts are quoted | Homes or businesses where the AC has stopped cooling, short cycles, or blows warm air | A frozen coil is almost always a symptom of something else. We find the root cause before recommending a repair. |
| Ductless Mini-Split Installation | Room-by-room load assessment, Outdoor compressor and indoor unit placement, Refrigerant line routing through small wall penetration, System tested through heating and cooling modes | Older Los Altos homes without existing ductwork, or spaces where adding ducts would require significant renovation | The location of the indoor unit affects coverage and airflow across the room. That placement decision is part of the planning conversation before anything is ordered. |
| Heating & Furnace Repair | Heat exchanger inspection, Ignition system and burner check, Airflow path and filter review, Diagnosis before repair is quoted | Homes with no heat, unusual furnace noises, or a system blowing cold air | A burning smell at the start of heating season can be dust on the heat exchanger. A persistent smell points to something that needs a diagnostic visit. |
| Emergency HVAC Service | No-heat and no-cool calls, Scope confirmed on the call, Price discussed before scheduling, System tested before visit ends | Situations where the system is completely down and comfort or safety cannot wait | We are open daily from 9:00 AM to 8:00 PM for emergency and short-notice calls. The scope and price are settled on the phone before anyone heads out. |
| Heat Pump Electrification | Load assessment and equipment sizing, Ducted and ductless options reviewed, Installation replacing both furnace and AC where both exist, Full system test before visit closes | Los Altos homeowners ready to move on from an aging gas furnace and looking for a system that handles both heating and cooling | The Bay Area's mild winters mean heat pumps operate efficiently here through most of the year. A load calculation confirms the right size before anything is ordered. |
| Seasonal Maintenance & Tune-Ups | Coil cleaning, Refrigerant level check, Electrical connection inspection, Filter assessment and full system test | Homeowners and property managers who want to catch small issues before they become failures mid-season | Scheduling a spring AC tune-up and a fall furnace check before each season starts means shorter wait times and fewer surprises when the system is needed most. |
| Indoor Air Quality & Air Filtration | Assessment of existing filtration setup, Review of what the air handler can support, Filter upgrade or filtration system installation, Airflow check after installation | Households concerned about allergens, particulates, or wildfire smoke affecting indoor air | Higher-rated filters restrict airflow more than standard ones. We confirm the air handler can handle the added resistance before upgrading. |
| Heat Pump Repair & Service | Refrigerant charge check, Reversing valve inspection, Coil and compressor condition, Repair confirmed before work proceeds | Properties where the heat pump has stopped heating or cooling, or short cycles through both modes | Heat pumps handle both heating and cooling from one system, so a fault in one mode often points to a shared component worth checking in both. |
| Ductwork Repair & Sealing | Duct inspection and leak detection, Sealing or repair where needed, Airflow assessment after sealing, Identification of rooms with uneven coverage | Homes with uneven room temperatures, a system that runs constantly, or a spike in energy bills without an obvious equipment cause | Fixing leaking ducts often makes a bigger difference to comfort and energy use than adjusting the equipment itself. |
| Wildfire-Smoke Air Filtration (MERV-13+) | Compatibility check on existing air handler, MERV-13 or higher filter installation, Airflow assessment after upgrade, Review of filter replacement schedule | Santa Clara County households affected by recurring wildfire smoke seasons who want filtration that goes beyond a standard residential filter | Standard one-inch filters are not rated to capture the fine particulates wildfire smoke carries. MERV-13 and higher addresses that gap, but the air handler needs to handle the added resistance without straining the blower. |
| Full System Installation & ReplacementMost Popular | Load calculation for the space, Equipment selection based on actual building needs, Full installation scope breakdown, System tested before visit closes | Homes or commercial spaces where repair costs have climbed or efficiency has dropped enough to show up in energy bills | A load calculation sizes the new system to the building rather than matching the old unit. Oversized equipment short-cycles and undersized equipment runs constantly. |
| Thermostat & Smart-Control Installation | Compatibility check with existing system, Wiring and installation, Calibration of the new control, Full system cycle test before leaving | Homeowners upgrading to a programmable or smart thermostat, or replacing a control that reads temperature incorrectly | Not every smart thermostat is compatible with every system. We check before ordering so the installation goes cleanly. |
How do I know whether to repair or replace my AC or furnace?
The short answer is to compare what the repair costs against what a new system costs and how much life the existing equipment has left. A system that has needed repeated attention in a short period, or one where the repair cost approaches a third or more of a replacement quote, is often a better candidate for replacement. We walk through both numbers on the call so you can make the comparison before committing to either path.
How often should I schedule a maintenance tune-up?
Once a year for each system is the practical standard. For a home that runs both heating and cooling, that usually means a furnace or heat pump check in the fall before cold weather arrives, and an AC or cooling-side check in the spring before temperatures climb. Scheduling before the season starts keeps wait times shorter and gives us a chance to catch anything that would cause a failure when the system is running hardest.
What does a seasonal tune-up actually cover?
A tune-up is not just a filter swap. It covers coil cleaning, a refrigerant level check, electrical connection inspection, a review of the ignition system on heating equipment, and a full system test that runs the equipment through its normal cycle. The goal is to find anything that is wearing, out of spec, or likely to cause a problem before it causes one.
System Checked Before Parts Are Quoted
We run a full diagnosis before any repair is recommended. That means the quote reflects what the system actually needs, not what a symptom suggests at first glance.
Why is one room in my house hotter or colder than the rest?
Uneven temperatures from room to room usually point to one of three things: leaking or poorly sealed ductwork that loses conditioned air before it reaches the far rooms, an undersized or oversized system that cannot maintain even temperatures across the whole space, or a blocked or closed supply register. A ductwork inspection and an airflow assessment together usually identify which of those is driving the problem.
What do strange noises from my HVAC unit usually mean?
Different sounds point to different problems. A banging or rattling noise often means something loose in the blower or the cabinet. A high-pitched squealing can indicate a belt or motor bearing issue on older equipment. A clicking that repeats without the system starting points to an ignition or control problem. A grinding sound usually means a motor bearing that is failing. None of these are sounds to run the system through and hope they clear on their own.
How does a dirty filter or coil affect system performance?
A clogged filter restricts the airflow the system needs to move heat effectively, which forces the equipment to run longer to reach the set temperature and raises energy use in the process. A dirty evaporator coil has the same effect on the cooling side, and a dirty condenser coil makes it harder for the system to shed heat outdoors. Either problem can eventually cause the system to overheat, short cycle, or freeze up. Checking the filter regularly and scheduling coil cleaning as part of a tune-up prevents most of those outcomes.
Findings Written Up After the Visit
Clear notes on what was found and what was done go with every visit. Property managers, landlords, and homeowners all get a record of the work rather than a verbal summary.
What causes a system to short-cycle?
Short cycling, where the system turns on and off in quick succession without completing a full heating or cooling cycle, usually comes down to one of a few causes. An oversized system is the most common: a unit that is too large for the space cools or heats it too quickly, shuts off, and then restarts before conditions stabilize. A refrigerant issue, a failing thermostat, or a dirty filter that causes the system to overheat and trip a safety switch can also produce short cycling. The diagnostic visit identifies which is driving it.
How does a refrigerant leak affect my AC or heat pump?
Refrigerant is what the system uses to move heat. A slow leak means the system has less of it to work with, so it runs longer and harder to produce the same result. Over time that shows up as reduced cooling or heating output, higher energy bills, and eventually a coil that freezes over. A refrigerant leak is not fixed by adding more refrigerant. The leak has to be found and repaired first, and then the system is recharged to the manufacturer's specification.
Code-Compliant Work on Every Job
Work is carried out to code on every job, whether the call is a straightforward repair or a full system installation. That matters when the work is inspected and when the home changes hands.
Is a heat pump a good fit for a home that currently has a gas furnace?
In most cases, yes, and the Bay Area climate makes it a particularly practical swap. Heat pumps handle both heating and cooling from a single system, so the installation replaces both the furnace and the air conditioner where both exist. The region's mild winters mean the equipment operates efficiently here through most of the year without the efficiency drop that affects heat pumps in colder climates. A load calculation confirms the right size for the home before anything is ordered.
How does the estimate and pricing process work?
The diagnostic or service-call fee is explained when you call, before anything is scheduled. Once the technician has assessed the system, the repair or installation price is confirmed before any work begins. What the visit covers is laid out up front. If a repair turns out to need a follow-up visit or a part that has to be ordered, that is communicated before the scope changes.
Is older equipment worth repairing, or does age alone make replacement the better call?
Age alone is not the deciding factor. A system that is older but has been maintained and has a straightforward repair in front of it may be worth fixing. A system that is older, has needed repeated repairs in recent seasons, and is facing a significant repair cost is a stronger candidate for replacement. We give you both numbers, the repair cost and a replacement quote, so the decision is based on actual figures rather than a general rule about age.
Call us at (650) 955-4592 to talk through your system, get a straight answer on pricing, and schedule service that fits your timeline.
(650) 955-4592