AC Repair
Frozen coils, failed capacitors and refrigerant leaks in a city where cooling season runs half the year. Diagnosed properly, quoted upfront.
Repair my ACServing San Marcos, TX
Plumbing and Cooling for Homes, Rentals and Everything Between
San Marcos is a college town, a river town and one of the fastest-growing cities on I-35. Radiant’s licensed plumbers and HVAC technicians serve all of it, with the price approved before we start.
Service Area
San Marcos, TX
Region
Austin & Central Texas
Home Services That Fit the Way San Marcos Lives
San Marcos sits halfway between Austin and San Antonio, and it has a little of both. Around the courthouse square and Texas State there are older homes, many of them now rentals, with plumbing and ductwork that have seen decades of tenants. Along the outer edges of the city, new subdivisions have gone up fast, with slab foundations on clay and builder-grade equipment that is now hitting the age where repairs begin. The San Marcos River and the springs that feed it are why the town is here, and the hard, mineral-rich water that comes out of the same aquifer is why we are.
Radiant has served Central Texas since 1999, and San Marcos falls squarely in our territory. The calls we handle most here are air conditioners that fail in the middle of a student move-in week, water heaters scaled up by hard water, drains in rentals that have been abused for years, and slab and yard leaks that show up as a spike on the water bill.
Homeowners and landlords get the same treatment: a licensed, background-checked technician, a plain explanation, and a written price you approve before any work starts. We will tell you honestly when a repair is the right call and when it is not, and financing is available when a replacement cannot wait for a better month.
- Landlord-friendly We coordinate with owners, managers and tenants and document what we find and fix.
- No surprise fees The quoted price is the price, weekend or holiday, honored for 72 hours.
- Guaranteed work Our Home Comfort Guarantee covers every visit, including a no-backup promise on drain clearing.
Services for San Marcos Homes and Rentals
Whatever the house was built, and whoever lives in it, one licensed team handles the plumbing and HVAC.
Drain Cleaning
Rental drains take a beating. We clear kitchen, tub and main-line stoppages and camera the line when it keeps coming back.
Clear the drainPlumbers
Toilets, faucets, disposals, pressure problems and repipes for older homes near campus and newer ones on the outskirts.
San Marcos plumbersWater Heater Repair
Hard water and heavy use wear out heaters fast. We flush, repair, or tell you honestly when the tank is finished.
Water heater helpWater Softeners
Aquifer water is very hard. A softener protects the equipment and fixtures in your home from years of scale.
Softener optionsLeak Detection
A high bill with no visible water usually means a slab or yard leak. We find the spot before anyone digs.
Find the leakAC Maintenance
A spring tune-up finds the weak parts before the first 100-degree week. Care Club members get two a year.
Book a tune-upLocal Knowledge
What San Marcos Does to Plumbing and HVAC
Spring water is hard water. The same Edwards Aquifer that feeds the San Marcos Springs supplies the taps, and it is loaded with dissolved limestone. Water heaters scale up, tankless units need descaling, and showerheads clog. A softener is the fix, and in a rental it is also protection for equipment you would otherwise replace every few years.
Rental wear. Homes near Texas State often turn over every August. Drains collect things drains should not, disposals get jammed, and small leaks go unreported until the ceiling stains. A plumbing inspection between tenants catches these while they are cheap.
Clay on the east side, rock on the west. New subdivisions east of I-35 sit on blackland clay that moves with the weather, so slab leaks and cracked sewer lines are the concern. West of the interstate the ground turns to limestone, and long service lines and pressure loss are more typical.
Half a year of cooling. Air conditioners here run from spring through October. Older homes with retrofit ductwork and new homes with leaky attic ducts both waste cooling. Sealing ducts is often the better first move before replacing a unit.
Freeze risk is real. The February 2021 freeze burst pipes in student housing and family homes alike. Insulated hose bibs, a known shutoff valve and a drip on the coldest nights prevent most of it.
San Marcos and Hays County
San Marcos is served from our South Austin office, a straight run down I-35.
Current Specials
Save on the work your home needs most.
Austin
HVAC
Last Chance HVAC Tune-up $59
Expires 12/31/2026
Austin
Plumbing
$50 Off Your Plumbing Call
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
Both Locations
Whole-Home
$50 Off Any Service
Expires 12/31/2026
Both Locations
HVAC
No Payments, No Interest For 6 Months on a New A/C System
Expires 12/31/2026
Nearby Service Areas
Frequently Asked Questions
Do you work on rental properties in San Marcos, and can a landlord schedule it remotely?
Yes. A large share of our San Marcos work is for owners and property managers who do not live nearby. You can schedule the visit, we coordinate access with the tenant, and you get the diagnosis and the quoted price before we do anything, so nothing is done without your approval. After the job, you get a clear record of what was found and fixed. For owners with several units, Care Club covers annual HVAC tune-ups and a plumbing inspection per enrolled system with no dispatch fees, which keeps small problems from becoming emergency calls in August.
Why does my San Marcos air conditioner freeze up in July?
Ice on the indoor coil or refrigerant lines means the coil is getting too cold, and there are two usual reasons. The first is airflow: a filter that has not been changed since move-in, a dirty evaporator coil, or crushed and leaking ductwork means not enough warm air passes over the coil. The second is low refrigerant from a leak, which drops the coil pressure and temperature. Turn the system off and let it thaw, change the filter, and if it ices again, call us. Running it frozen can damage the compressor, which turns a modest repair into a much bigger one.
San Marcos sits between Austin and San Antonio. Does that change anything about my service?
No. San Marcos is part of our Austin service area, served from our South Austin office, and nothing about the service changes because of where the city sits on the map. The pricing, the licensing, the 24/7 availability and the Home Comfort Guarantee are the same in every city we serve. You call one number, tell us what is going on, and a licensed technician quotes the price before any work starts.
What does hard water do to a tankless water heater here?
It scales the heat exchanger. A tankless unit heats water on demand through narrow passages, and the calcium in San Marcos water plates onto those passages every time the unit fires. Over a year or two without treatment, flow drops, the unit throws error codes and efficiency falls. The fix is prevention: a softener ahead of the unit and an annual descaling flush. If you already have a tankless heater that is struggling, we can descale it and check whether the exchanger is still sound. If it is too far gone, we will say so and price a replacement honestly.
What Our Customers Say
Don't just take our word for it — hear from our satisfied customers
★★★★★
Our 18 year old HVAC system finally gave out this past week, so we reached out to Radiant to see what could be done. They sent a tech out named Bryan the same day, and he did a great job looking over the entire HVAC system. He was friendly and helpful in explaining everything that he saw, and our options moving forward. We decided to replace the entire system, so we met with Jacob (same day thankfully) to find the best HVAC system for our needs. Jacob was friendly, professional, and did a great job explaining the different options on offer. Radiant was able to set-up next day install, which was much appreciated, because the temps were still going to be cold in the coming days.
The install team consisted of Carlos and Pablo, who were very courteous and professional, and were kind enough to answer any questions I had regarding the install. They did a great job installing our new HVAC system, and were tidy which is always appreciated! Before they left, they explained everything that had been done, and showed me photos of the work.
Our entire experience from start to finish was great. I appreciate that they send photos of who is coming to your home too. Friendly, kind, professional team members, and good work all the way around. Thanks Radiant!
The install team consisted of Carlos and Pablo, who were very courteous and professional, and were kind enough to answer any questions I had regarding the install. They did a great job installing our new HVAC system, and were tidy which is always appreciated! Before they left, they explained everything that had been done, and showed me photos of the work.
Our entire experience from start to finish was great. I appreciate that they send photos of who is coming to your home too. Friendly, kind, professional team members, and good work all the way around. Thanks Radiant!
★★★★★
This is the first time I’ve used radiant my neighbor recommended them…. I called them today and they set me up an appointment on the same day. I was totally shocked at that and the service call was only $39!!…. Highly recommend them Danielle showed up and he was a great guy and he put up with all my wishy-washiness and I had to hurry him because I was heading to church and he got caught in a lot of traffic getting here he even would’ve installed the part that broke but I Didn’t have the time tonight….. He was patient with me and just told me to call the office first thing in the morning and get a service call set up…. Thank you so much Radiant!!….
With another cold front coming in tomorrow now I just hope they can get me scheduled for a separate call tomorrow but I have a feeling they will. They are such a great company!!😊😊
With another cold front coming in tomorrow now I just hope they can get me scheduled for a separate call tomorrow but I have a feeling they will. They are such a great company!!😊😊
★★★★★
I had Radiant Plumbing replace my tankless water heater, damaged in the Feb. 2021 snowmageddon storm with a new unit. The process was smooth and professional from start to finish. The plumber, James, was extremely knowledgeable and thoroughly explained my options to me. The cost and time to perform the installation were just as estimated. When he was done, James explained how to maintain the system, what service would be needed and how to perform it, and answered all of my engineering geek questions. It was a thoroughly positive experience. I have used several different plumbers in Austin over the past 15 yrs, but my search is over - I will not hesitate to call Radiant next time and would recommend them unreservedly.
8/9/23 Update: I have subsequently used Radiant for a toilet repair, faucet installation (Danny), and drain work (Ezekiel) and they have continued to impress with knowledgeable, friendly plumbers and quality work.
8/9/23 Update: I have subsequently used Radiant for a toilet repair, faucet installation (Danny), and drain work (Ezekiel) and they have continued to impress with knowledgeable, friendly plumbers and quality work.
*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.
