Most requests for AC repair in Round Rock, TX, come from houses that were built fast, in large numbers, in the same few years. That pattern matters: when a whole street of homes got its equipment in the same season, the parts tend to fail in the same summers too. Here is what is specific to keeping a Round Rock house cool, warm and safe, and what to expect from the company you are connected with.
Austin AC Service does not send technicians or fix equipment. It is a free referral line. Dial (737) 378-9016, tell the automated assistant whether it is a cooling or heating problem, then give your name, number, ZIP and a description of the trouble. The call is then handed to an independent, locally owned HVAC company in the Round Rock area that holds a Texas ACR contractor license. You deal with that company directly.
A Round Rock house and its AC usually date from a boom
The City of Round Rock's own population history tells the story. It counted 2,811 residents in 1970, 12,740 in 1980, 30,923 in 1990, 61,136 in 2000 and 99,887 in 2010. The 2020 Census put the city at 119,468. During the 1970s the city grew faster than any other town of its size in the Austin metro, and in the 1980s it nearly tripled again.
Each of those jumps left a layer of houses with equipment chosen by the builder, often the most affordable unit that met code that year. The older layer, near downtown and along Brushy Creek, has mostly been through two or three systems already. The newer layers in places like Teravista, Forest Creek and Paloma Lake are reaching the age where original systems start asking for bigger repairs. Knowing which layer your house belongs to helps you read a quote.
When your Round Rock house was built, and what that means for the system
A general guide, not a diagnosis. A house that has had its system replaced, or a remodel, will not fit its row. The equipment's data plate, usually on the side of the outdoor unit, shows when it was made and which refrigerant it uses.
| Built | Likely situation now | Questions worth asking |
|---|---|---|
| Before 1990 | On a second or third system. Original ducts may still be in place, leaky or undersized for today's equipment. | Have the ducts been tested or sealed? Is the system sized for the house as it is now? |
| 1990s | Any system still running R-22 refrigerant is living on borrowed time, because U.S. production of R-22 ended in 2020. | What refrigerant does it use? What would a recharge cost compared with a replacement? |
| 2000s to early 2010s | Many homes on original or first-replacement R-410A equipment, now 12 to 25 years old. Capacitors, fan motors and coils start to fail. | Is a repair a sensible option at this age? Can I see the repair and replacement prices together? |
| Mid 2010s to 2024 | Mostly R-410A systems with useful life left. R-410A remains available for service, and no federal rule forces replacement. | Is the system still inside the manufacturer's parts warranty, and was it registered? |
| 2025 and later | New equipment uses lower-impact A2L refrigerants such as R-454B or R-32, which call for matching indoor and outdoor parts. | Was the indoor coil replaced to match the outdoor unit? Was the permit inspected? |
Power out, or AC out? Sorting it in Round Rock
Most of Round Rock is in Oncor's delivery area, which means two companies are involved in your electricity: Oncor owns and repairs the poles, wires and meters, and the retail provider you picked sends the bill. Neither one works on air conditioners. Before you call anybody, it helps to know which problem you have.
- The whole house is dark. That is an outage. Report it to Oncor. Many people switch the thermostat to Off until power is restored and steady, then turn the system back on.
- Lights work, the AC does not. Check the thermostat mode and batteries, then look for a tripped breaker for the air handler or condenser and reset it once.
- The breaker trips again. Leave it off. A breaker that trips twice is pointing to a fault a licensed technician needs to find.
- The system runs but blows warm air. Look at the filter and the outdoor unit, then turn the system off and call if ice or a humming, motionless fan shows up.
Two kinds of ground under one city
Round Rock sits on the Balcones Escarpment. Roughly east of I-35 the land is flat Blackland Prairie, with the heavy black clay that local farmers once called black waxy and that made Round Rock a cotton town. West of the interstate it turns into the edge of the Hill Country, with thin, rocky soil over limestone.
The east side's clay shrinks in drought and swells after heavy rain. Over a few years that movement can tip a condenser pad out of level, strain the copper lines where they enter the wall, and shift the slope of a condensate drain so water stops flowing the way it should. On the rocky west side, pads tend to stay put, but lots on slopes can send runoff toward the outdoor unit. Either way, a careful technician notices: manufacturers call for outdoor units to sit level, and a drain line that has lost its fall will keep clogging no matter how often it is cleared.
Before a replacement in Round Rock
A new system is a bigger decision than a repair, and a few local details are easy to miss.
- The city permit. Round Rock issues standalone mechanical permits for HVAC work through its online portal at permits.roundrocktexas.gov, and the job is inspected. The contractor normally applies. Make sure the quote says so.
- The right rebate program. Austin Energy rebates are for Austin Energy customers. In Oncor territory, ask your retail provider and the contractor what efficiency programs currently apply.
- A load calculation. Round Rock homes have often gained insulation, windows or a converted garage since they were built, so the right size may not match the old unit's label.
- The ducts. In pre-2000 homes especially, ask whether the ducts were inspected. A new unit on leaky ducts still cools the attic.
- The license number. Look it up at tdlr.texas.gov before you sign.
Why Round Rock homeowners call the line
One number, any hour
A 2 a.m. breakdown during an August heat wave or a January freeze gets the same answer as a Tuesday afternoon call. The line costs callers nothing.
Routed by ZIP code
Give a 78664, 78665 or 78681 ZIP and the call goes to an independent company that serves Round Rock, rather than whoever happens to rank first in a search.
Licensed, and you can check
Each company on the other end of the line is licensed by TDLR as an air conditioning and refrigeration contractor. Ask for the number and confirm it.
Gas and electric covered in the summary
Say whether your heat is a gas furnace or a heat pump when you describe the problem. That detail can be part of the summary the company hears before it picks up.
Services Round Rock homes need most
In summer, AC repair covers the usual: no cooling, short cycling, iced lines and attic drains that overflow into a ceiling. For a system that quits at night or on a holiday weekend, see emergency AC and heating repair. Round Rock homes heat with either a gas furnace, with gas delivered by Atmos Energy, or an electric heat pump, and both get tested by a hard freeze, so heating repair matters every winter, and a fall check before the first hard freeze is cheaper than a call during one. Owners of original 2000s equipment should read AC installation and replacement before a breakdown forces the decision, and a spring tune-up catches the weak capacitor before July does.
AC Repair
Warm air, a unit that hums but will not start, ice on the lines or water in the ceiling. What a proper diagnosis covers and what to ask before a repair.
Heating and Furnace Repair
Gas furnaces, heat pumps and emergency heat. Why Austin heating systems fail on the first cold night and what a good technician checks.
AC Installation and Replacement
Repair or replace, sizing by load calculation, the R-454B refrigerant change, permits, and Austin Energy rebates.
HVAC Maintenance and Tune-Ups
A spring cooling check before the heat and a fall heating check before the first freeze, and what a real tune-up includes.
How a Round Rock call works
- Call any hourAn automated assistant answers (737) 378-9016 and asks whether it is about cooling or heating.
- Describe the problemGive your name, a callback number, your city or ZIP and what the system is doing.
- Get put throughThe call goes to an independent, locally owned HVAC company, which hears a short summary before it picks up.
- Deal with them directlyThat company diagnoses, quotes, does the work and is paid by you. If it cannot answer, it gets your details to call back.
How this line works: Austin AC Service is a free phone line, not an HVAC company. It does not repair, install, quote or schedule work and holds no license. Calls are transferred to independent, locally owned HVAC companies that hold Texas air conditioning and refrigeration contractor licenses. Those companies may pay Austin AC Service a referral fee. You never pay the line. How it works.
Check any license yourself. Texas air conditioning and refrigeration contractors are licensed by the Texas Department of Licensing and Regulation. Ask for the license number and look it up at tdlr.texas.gov (opens in a new tab).
Areas next to Round Rock
The full list of Austin-area cities the line answers for: