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When the AC quits on a 104 degree afternoon or the wall furnace will not light on a cold night, you need a technician, not a voicemail.
Our own technicians repair, replace and maintain air conditioners, furnaces, heat pumps, ductless systems and ductwork across Pasadena and the San Gabriel Valley. Call (626) 879-0711 at any hour.
We repair, install and maintain heating and cooling systems for homes and businesses in Pasadena and nearby San Gabriel Valley cities, from Altadena and South Pasadena to Arcadia, Monrovia and Glendale. That covers central AC, gas furnaces, wall and floor furnaces, heat pumps, ductless mini-splits, ductwork and indoor air. Call (626) 879-0711. The phone is answered 24 hours a day, every day, and you talk to a person.
How we work
Most HVAC calls in Pasadena start the same way: something that worked yesterday is not working today. The air handler hums but the vents blow warm, the furnace clicks and shuts off, or a breaker trips every time the outdoor unit starts. When you call, a person answers, asks what you are seeing and hearing, and schedules a technician. At Marco's Heating & Air the technician who arrives is part of our own crew, carries common parts on the truck, and tests the system before naming a cause. You hear what failed, why it failed, and what the repair costs before any work starts. If the honest answer is that a repair is not worth the money, you hear that too.
The homes we work in cover more than a century of building. A 1912 Craftsman may still heat with a gravity wall furnace and cool with window units. A 1950s ranch often has a gas furnace in the hall closet feeding attic ducts, with a split AC added decades later. Newer homes and backyard ADUs lean toward heat pumps and ductless mini-splits. Each setup fails in its own ways, and each needs a technician who knows the difference between a worn part and a design problem. We work on all of them, from a single thermostat swap to a full system replacement with new ductwork.
Pricing stays plain. The technician explains the options at the house, writes down the price, and starts only after you agree. Where the city requires a permit for a replacement, we handle it, and when California's Title 24 rules call for duct leakage testing on a new AC or furnace, that test is scheduled as part of the job instead of showing up as a surprise. Ask about current PWP, SCE or SoCalGas rebates and state heat pump incentives when funding is open, and we will tell you which ones fit your equipment.
Every service
Below is every service we offer, grouped the way problems usually show up: cooling, heating, heat pumps and ductless, ducts and attic, indoor air, and full systems and commercial work. Each page explains what fails, what the technician checks, and typical Pasadena price ranges, so you know what to expect before you call.
Air conditioner repair, installation, replacement and tune-ups, plus the specific failures that hit hardest in Pasadena summers: refrigerant leaks, compressors, evaporator coils and indoor water leaks.
Gas furnace repair, installation, replacement and maintenance, along with the wall furnaces, floor furnaces and boilers still heating many Craftsman, Spanish Revival and postwar homes.
Heat pump repair, installation and maintenance, gas to heat pump conversions, ductless mini-splits for rooms that never cooled well, and heating and cooling for new backyard ADUs.
Duct repair, replacement, cleaning and sealing for hot Pasadena attics and crawlspaces, plus whole house fans and attic insulation that cut how hard the AC has to work.
Indoor air quality work for dust, Santa Ana days and wildfire smoke: whole home air purifiers, UV air sanitizers and whole home humidifiers for dry winter air.
Smart thermostats, zoning, full system replacement, inspections, maintenance plans, 24/7 emergency repair, and commercial service including rooftop units for shops, offices and restaurants.
Warning signs
Most heating and cooling failures give some warning before they quit completely. Catching them early usually means a smaller repair, and it keeps you from losing the AC on the hottest day of the year. Call when you notice any of these.
If the thermostat calls for cooling and the supply air feels barely cooler than the room, the cause can be low refrigerant, a failed capacitor, a frozen coil or a dirty condenser that cannot shed heat.
A system that starts, runs a few minutes and shuts down is often oversized, overheating or reacting to a bad sensor. Short cycling wears out compressors and igniters and leaves some rooms warm and others cold.
Squealing points to a motor or belt, grinding to worn bearings, and a loud bang at furnace ignition to delayed ignition from dirty burners. Each one is worth a look before it turns into a larger failure.
In a Pasadena summer an air conditioner pulls a lot of water out of the air. A clogged condensate drain or cracked pan can soak a closet floor, stain a ceiling below an attic unit, or ruin drywall.
When electric bills climb but your habits have not changed, the system may be running longer to do the same work. Leaky attic ducts, a dirty coil and failing blower motors are common reasons.
A dusty smell on the first cold night is normal for a few minutes. A steady electrical burning smell, or any smell of gas, is not. For gas, leave the home and call SoCalGas or 911 first.
AC size estimator
Use the estimator below to get a ballpark air conditioner size for your home. Enter the square footage, how well the attic and walls are insulated, how much afternoon sun the house gets, and the ceiling height. Treat the result as a rough starting point only. The real answer comes from a room-by-room load calculation, which our technician does before recommending any equipment.
Adjust the inputs to see a range.
A room-by-room load calculation at your home decides the final size.
Step by step
Call (626) 879-0711 at any hour. A person answers, asks what the system is doing, takes your address and the equipment type if you know it, and gives you a realistic arrival window.
On arrival the technician looks at the whole system, not only the part you mentioned. That means electrical readings, refrigerant or gas pressure, airflow, the condensate drain and the thermostat wiring.
You get a plain explanation of what failed and why, with the worn part or the meter reading shown when it helps. If there is more than one way to fix it, each option is laid out.
The price is quoted before any work starts. Nothing is replaced until you agree, and if you decide to wait, you know what the risk of waiting looks like.
After the repair the technician runs the system through a full cycle, checks temperatures and safety controls, cleans up the work area, and tells you anything worth watching over the next few weeks.
Why homeowners call us
The person at your door works for us. We do not hand your job to someone else, so the technician who tested the system is the same one who answers for the repair and the result.
Heat waves and cold snaps do not keep office hours, and neither do we. The phone is answered day and night, weekends and holidays included, by someone who can put a technician on the schedule.
Wall furnaces from the 1940s, floor furnaces under Craftsman floors, attic ducts in ranch homes, new heat pumps and ductless heads in backyard ADUs. We work on the full range found in Pasadena houses.
We quote the price before we start the work, explain the repair or replace math in plain numbers, and never push a new system when a reasonable repair will keep the old one running well.
Local conditions
Pasadena summers are hotter than the coast. Inland afternoons often reach the high 90s and push past 100 F during heat waves, and attics get far hotter than that, which is hard on ducts, refrigerant lines and air handlers installed up there. Santa Ana wind days bring dry, dusty air that loads filters and outdoor coils fast, and wildfire smoke seasons make good filtration matter indoors. Winter is mild by day, but nights drop into the 30s and 40s, especially near the foothills, so heating still gets real use. Many older Pasadena homes were built long before central air, with wall furnaces, floor furnaces and ducts squeezed into tight crawlspaces and attics, and those details shape every repair.
We work from two offices: our Old Pasadena office on East Colorado Boulevard and our head office in Duarte. That keeps us close to the whole San Gabriel Valley, from Altadena, La Cañada Flintridge and Sierra Madre along the foothills to South Pasadena, San Marino, Arcadia, Monrovia, Temple City and El Monte, and west to Glendale and Burbank. Homes near the areas burned in the January 2025 Eaton Fire, in Altadena and parts of Pasadena and Sierra Madre, sometimes still need ducts inspected and cleaned of smoke and ash, and rebuilt homes need new systems sized and installed with care.
Where we work
We cover Pasadena neighborhoods from Bungalow Heaven and Madison Heights to Hastings Ranch, Linda Vista and San Rafael, plus the surrounding cities of the San Gabriel Valley, the foothill communities, and nearby parts of Los Angeles, San Bernardino and north Orange counties. Find your area below for notes on local homes and common problems.
See every area we serve, including Los Angeles County, San Bernardino County and north Orange County.
From the blog
Short, practical guides on keeping a Pasadena home comfortable: what to check before you call, how to weigh repair against replacement, and how heat, dust and smoke affect your equipment.
Hot, dry Santa Ana winds push dust, leaves and grit into every gap. Here is what that does to filters, condenser coils and attic ducts, and a simple after-wind checklist for San Gabriel Valley homes.
Thousands of older San Gabriel Valley homes still heat with a gas wall furnace. Here is what to look at before the first cold night, what a technician checks, and when repair stops making sense.
Pasadena's mild winters and hot summers make heat pumps a strong fit, but a gas furnace still makes sense in some homes. Here is how to weigh climate, electrical capacity, ducts and rebates.
All blog posts or check typical numbers in our HVAC price guide.
Questions
Yes. The phone at (626) 879-0711 is answered 24 hours a day, every day of the year, including weekends and holidays. A person takes the details, asks a few questions about what the system is doing, and schedules a technician. For a no-heat or no-cool problem during extreme weather, we work to get someone to you as soon as a technician is free.
The technicians are our own crew. We do not pass your job to an outside company. The technician who tests your system is the one who explains the problem, quotes the price and does the repair, so you deal with the same people from the first call to the final check of the system.
Common repairs such as a capacitor, contactor, igniter, flame sensor or clogged drain usually land in a range of a few hundred dollars including the visit, while compressor, coil or heat exchanger problems cost far more. Our price guide lists typical ranges for each service. The final price comes after the technician sees the system, and we quote it before we start the work.
Age alone does not decide it. We look at the size of the repair compared with the value of the system, how often it has failed lately, the refrigerant it uses, and whether the equipment was sized right for the house. If a repair makes sense, we say so. If replacement is the better buy, we explain why in plain numbers and size the new system with a proper load calculation.
Yes. Many Craftsman, Spanish Revival and postwar homes in Pasadena still use gravity wall furnaces or floor furnaces. We repair them, check venting and the gas valve for safe operation, and when a unit is past saving, we explain the replacement choices, from a new wall furnace to a ducted or ductless heat pump that also adds cooling.
We handle the permit where the city requires one, in Pasadena and the surrounding cities we serve, and we schedule any duct leakage testing that California's Title 24 rules call for. For rebates, ask about current PWP, SCE or SoCalGas rebates and state heat pump incentives when funding is open. We will tell you what your new equipment may qualify for.
Call our Pasadena line any hour. A person answers, asks a few questions about the system, and gives you an arrival window.