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When your water heater goes cold, life at home quickly grinds to a halt. At Radiant Plumbing & Air Conditioning, we know San Marcos families depend on reliable hot water every day – from morning showers to nightly dishwashing. Our plumbers are experts in both traditional tank water heaters and modern tankless systems, so no matter the model, our licensed team will keep it running at its best. And because hot water emergencies don’t always happen during business hours, our emergency plumbers are available 24/7 to restore comfort fast. Whether it’s a minor repair, a full replacement, or urgent service in the middle of the night, Radiant delivers lasting solutions with upfront pricing and our Home Comfort Guarantee. With us, reliable hot water is always just a call away.
Most water heater breakdowns can be prevented with regular maintenance, and that’s exactly what Radiant’s Care Club delivers. As a member, San Marcos homeowners receive annual HVAC plumbing inspections that include flushing your water heater, checking for leaks, testing valves, and spotting corrosion early. These routine checkups extend the life of your system, improve efficiency, and help you avoid costly emergency repairs. Plus, you’ll enjoy 24/7 peace of mind with no dispatch fees, a 10% discount on services, and priority scheduling when problems arise. With Care Club, your water heater stays protected, your energy bills stay low, and your hot water is always ready when you need it.
At Radiant Plumbing & Air Conditioning, water heater service isn’t just about fixing the problem in front of us — it’s about giving you confidence that the repair will last. That’s why every job is backed by our Home Comfort Guarantee. From upfront pricing with no hidden fees to expert installations and lasting workmanship, we stand behind our work 100%. Whether it’s repairing a tank system, installing a new tankless unit, or responding to an emergency, our licensed plumbers bring integrity, precision, and care to every job. If it’s not done right, we’ll make it right — that’s the Radiant promise.
We proudly service the following cities and neighborhoods across San Antonio, TX:
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No hot water, rusty tap water, or a tank that won’t stop dripping? San Marcos homes see it all. Our local hard water from the Edwards Aquifer puts extra stress on both tank and tankless systems, building scale on heating elements and inside heat exchangers. Radiant fixes the problem at the source: we test thermostats and gas valves, flush sediment, descale tankless units, and check anode rods so your heater runs safely and efficiently again. If your unit is in the garage or attic, we inspect the drip pan and drain line so a small leak doesn’t turn into a ceiling repair.
Common issues we solve include lukewarm water (failed heating element, undersized unit, or mixing valve problem), long wait times (recirculation pump issues), pilot outages or ignition faults, popping/rumbling from sediment, and T&P valve discharges caused by thermal expansion or high street pressure. We also verify pressure-reducing valves and expansion tanks – two small parts that prevent repeat leaks and extend equipment life. For older homes near The Square and student rentals by Texas State, we tidy up past “band-aid” fixes and bring everything back to clean, labeled, code-compliant condition.
Thinking ahead? We’ll tell you honestly when repair makes sense and when a water heater replacement will save money long-term. If a new water heater is the better call, we size it to your family’s usage, review efficiency options (high-recovery tanks, hybrid heat pump models, or tankless), and install it with the right pan, shutoffs, and a proper T&P discharge without shortcuts.
Related San Marcos services:
From Spring Lake to the Outlet corridor, you’ll get straight answers, transparent pricing, and repair-first solutions from licensed pros who respect your home. Need hot water back today? We’ll get it done—clean, safe, and built to last. We Answer the Call.