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San Antonio AC Installation
Why Oversizing Is the Most Common Mistake in a San Antonio Install
It sounds sensible: hotter city, bigger unit. In practice a too-large air conditioner is the reason so many San Antonio homes feel cold and damp at the same time. The system hits the thermostat setting in a few minutes and shuts off before the coil has had time to pull moisture out of the air. The house never dries out, the equipment cycles on and off constantly, and the parts wear out early. With Gulf humidity sitting over Bexar County from April to October, the right size matters more here than almost anywhere in Texas.
So we calculate the load instead of copying the nameplate on the old unit. Square footage, ceiling height, window orientation, insulation, how many people live there, and how the ductwork is actually performing. A two-story home in Stone Oak with west-facing glass, a single-story 1980s house in Universal City with a low attic, and a new build in Alamo Ranch with a sealed envelope each need something different. We have been installing systems across San Antonio since 1999, and our Wye Drive office holds Texas HVAC license TACLB138286E.
The general process, from equipment choices to what a permit covers, is on our air conditioner installation page. Below is what changes when the house is here.
- Load-calculated, not guessed Every replacement starts with a heat-load calculation and a look at the ductwork, not the old unit’s tonnage.
- Manager quality review Under the Home Comfort Guarantee, HVAC installs over $3,000 are reviewed by a manager before the job is closed.
- Financing that fits a big purchase No interest, no payments for 6 months through Service Finance Company, subject to credit approval.
Repair or Replace?
When a San Antonio System Is Telling You It Is Done
None of these alone means you need a new air conditioner. Two or three together usually do, and we will show you the math either way.
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It has cooled this house for 12 to 15 summers or more
A San Antonio cooling season is long enough that equipment ages faster here. A unit from the mid-2000s has done the work of a much older system in a milder climate.
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You paid for a repair last summer and the one before
Once repairs come every year, you are funding an old system in installments. A new one turns that into predictable comfort.
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The system still runs on R-22
Older refrigerant is scarce and costly. A significant leak on an R-22 system almost always tips the decision toward replacement.
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Cold rooms, sticky air, and mildew smells
The signature of an oversized or single-stage unit that cannot keep up with humidity. A properly sized variable-speed system solves it.
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Summer bills keep climbing with no change in habits
Efficiency falls as coils corrode and compressors wear. With this many run hours a year, that loss shows up on the bill quickly.
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You are adding on, converting a garage, or finishing a second floor
The existing system was sized for the old house. Additions in older Alamo Heights and Monte Vista homes often need a second system or a ductless unit.
What We Install
Cooling Equipment for San Antonio Homes
From a straight replacement of a failed condenser to a complete system with new ductwork and controls.
- Central split systems Matched condenser and indoor coil or air handler, sized from the load calculation and installed with a new pad, line set and drain.
- Two-stage and variable-speed systems Longer, gentler cycles that dry the air properly. The best answer to a clammy house and the most efficient option for a long cooling season.
- Heat pumps One outdoor unit that cools all summer and heats through a mild San Antonio winter. Popular in all-electric neighborhoods. See our San Antonio heat pump page.
- Ductless mini-splits For historic homes without ducts, casitas, garage apartments and the one room the central system never reaches.
- Air handlers and ductwork Attic air handlers, return upgrades and duct repairs so the new equipment is not choked by 30-year-old flex duct.
- Smart thermostats and zoning Controls that manage humidity as well as temperature, and zoning for two-story homes where upstairs runs hot.
The Install
From First Visit to First Cold Night of Sleep
No pressure, no mystery. You see the options, the numbers and the schedule before anything is ordered.
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Home evaluation and load calculation
We measure the house, inspect the ductwork and attic, and check the electrical supply to the condenser. Then we run the numbers.
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Options in writing
Usually two or three systems at different price points, with what each does for comfort and bills. The quote is honored for 72 hours, and there are no hidden fees.
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Installation day
Old equipment out, refrigerant recovered properly, new system set, brazed, evacuated, charged and commissioned. Many replacements can be finished in a day.
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Manager review and walkthrough
We show you the thermostat, the filter and the drain, register the equipment, and a manager reviews the job under the Home Comfort Guarantee.
Current Specials
Save on the work your home needs most.
San Antonio
HVAC
25% Off Select Air Purifiers & Filters
Expires 12/31/2026
San Antonio
HVAC
Up To $2,500 OFF Full HVAC System!
Expires 12/31/2026
San Antonio
HVAC
Buy a Complete HVAC System, Get a Furnace FREE!
Expires 12/31/2026
San Antonio
HVAC
Last Chance HVAC Tune-up $68
Expires 12/31/2026
Both Locations
HVAC
Up to $200 off Duct Cleaning
Expires 12/31/2026
Both Locations
HVAC
$99 Furnace Tune-Up
Expires 12/31/2026
Thinking About Replacing Before Next Summer?
Spring and fall are the easiest times to schedule. Get a written quote with no obligation.
What Our Customers Say
Don't just take our word for it — hear from our satisfied customers
★★★★★
Alex performed the winter service on my unit. This business along with Alex, are very professional and upfront about everything. To be transparent, this is the maintenance included with the purchase of a unit from them. I was informed about everything to include pictures as proof. I was told that my unit is 100% and very clean and again pictures to prove it. I was reccomended this business by a friend and glad he did. The initial purchase experience was also amazing. I had contacted 5 other businesses to get quotes about a new unit as my upstairs unit failed. 2 were outrageous quotes and I am technically still waiting on the other 3. On every instance of getting a quote, I waited about 1 week. Luckily my house has two units but still, un acceptable especially during the summer. I guess they all had so much business they did not care for mine. When I called this business not only did they come out the same day, I had the new unit installed with in 48 hrs. Oh and let's not forget the quote they gave me was the lowest of all. I can say enough good things about this business. Keep up the great work.
★★★★★
We needed a new air conditioning system because ours was over 15 years old. I decided to get several estimates from different companies here in San Antonio. Each company seemed to have outrageous prices and wanted to put me into something that was above what I needed. I decided to try one more company, Schmidt Mechanical. I went on their website early in the morning and filled out my information asking for someone to contact me. By the end of the same day, Jared was sitting at our table. I told him specifically what I wanted and what I did not want, since I had gained quite a bit of information from my interaction with other companies. We had a lot of fun sitting at the table and talking about many things, but when he put pen to paper, and gave us three choices of product, service, warranties, etc., we knew right away that Schmidt Mechanical was far superior to other companies in town. We sealed the deal and decided that the following Monday would be installation day. Keeping in mind, that would be one week from the day that we sat down and closed. The very next night, our old unit decided to call it quits and we still had six more nights to go until we get the new system. I called the after hours service line and they sent someone out by 10 o’clock that night, but unfortunately the unit couldn’t even carry electricity to be repaired. They didn’t even charge me for that service call. The next morning I called the company to ask if they had any suggestions on what we could do in the meantime. They put their heads together to come up with a solution. We were very thankful to Keith when he called to tell us they were able to rearrange schedules and carve out time in order to have our new AC unit installed two days later. Schmidt Mechanical - professional, honest, dependable, excellent customer service -- a company you will not regret doing business with. Thank you Team Schmidt!
★★★★★
I would highly recommend Radiant Plumbing. After our 17 year old system broke we bought a new AC unit from Radiant. All the people I dealt with were highly professional, explained everything well and were thorough in their inspection. They were very easy to contact, including a number customers can text with concerns or questions. They kept me well informed through the whole process. They even installed at no cost a portable AC to keep us cool before the installation. The installers, Arturo and Rene, were prompt; they arrived at the exact time we were told, and were very respectful of our home.
Radiant helped us quickly; the AC broke Thursday evening, we scheduled the repairman to come Friday, and Saturday they installed the new unit. I know it isn't always able to happen that fast but it was an extra bonus and relief to finally find an AC company that is actually available and answers the phone, unlike A US Air Conditioning, and is efficient and thorough with no high pressure salesmen, unlike ARS.
Thank you Radiant!
11/4/2020 - update
Had CJ out for the system check and he was very professional, informative, and respectful. He had some recommendations and was able to get us a replacement part for free even though we were just outside the 2yr warranty. It was a very unexpected blessing and I greatly appreciate him and the whole Radiant team.
Radiant helped us quickly; the AC broke Thursday evening, we scheduled the repairman to come Friday, and Saturday they installed the new unit. I know it isn't always able to happen that fast but it was an extra bonus and relief to finally find an AC company that is actually available and answers the phone, unlike A US Air Conditioning, and is efficient and thorough with no high pressure salesmen, unlike ARS.
Thank you Radiant!
11/4/2020 - update
Had CJ out for the system check and he was very professional, informative, and respectful. He had some recommendations and was able to get us a replacement part for free even though we were just outside the 2yr warranty. It was a very unexpected blessing and I greatly appreciate him and the whole Radiant team.
Maintenance Membership
Join the Care Club
Home maintenance for $9.99 a month.
Care Club members get two HVAC tune-ups and a plumbing safety inspection every year, priority scheduling, no dispatch fees — ever — and 5% off every repair.
- Priority scheduling
- Seasonal HVAC tune-ups
- Annual safety inspection
- Exclusive member discounts
- Free dispatch on repairs
- No long-term contracts
San Antonio AC Installation Questions
How big an air conditioner does a San Antonio house need?
There is no rule of thumb we trust, because two houses with the same square footage can need very different equipment. A load calculation accounts for the direction the windows face, the attic insulation, the ceiling height, how leaky the ductwork is, and how many people and appliances add heat. What we can say is that in San Antonio humidity, bigger is rarely better. An oversized system cools the air quickly and shuts off before it has removed enough moisture, so the house feels damp and the equipment short-cycles itself to an early death. We size for the actual load and, where the budget allows, recommend variable-speed equipment that runs long, slow cycles and keeps humidity in check.
Does a new AC installation in San Antonio need a permit?
Replacing HVAC equipment is permitted work in San Antonio and in most of the surrounding cities we serve, and we pull the permit as part of the job. The inspection protects you: it confirms the equipment is matched, the refrigerant lines and drain are done right, and the disconnect and breaker are correct for the new unit. A contractor who offers to skip the permit is saving themselves time at your expense, and an unpermitted replacement can become a problem when you sell the house. Our San Antonio license is TACLB138286E, and it is on every quote.
My condenser died but the indoor unit seems fine. Do both have to go?
Sometimes, but it is usually a false economy. The condenser and the evaporator coil are designed as a matched pair, and mismatched equipment loses efficiency, can void the manufacturer warranty, and may not work at all if the two use different refrigerants. Newer systems use refrigerants that are not compatible with older coils. If the indoor coil is only a few years old and matches, we will say so and save you the money. If it is the same age as the failed condenser, replacing both is the honest recommendation, because the coil is next in line to fail and you would pay the labor twice.
What does financing look like for a new system?
Radiant offers financing through Service Finance Company, LLC. The current program is no interest and no payments for six months, then 12.95% APR for 120 months, or 12.95% APR for 180 months, subject to credit approval. Many San Antonio homeowners use the six-month window to spread the cost of a replacement that came at a bad time, such as a compressor failure in August. We go over the options in writing on the estimate visit, and there is no pressure to finance if you would rather pay another way. Details are on our financing page.
*Offers cannot be combined with other promotions or applied to dispatch fees. No cash value. Must present offer at time of service. Call for details.
