When your water heater stops working, panic can set in fast—especially if your morning shower runs ice-cold. Across Austin and San Antonio, this is one of the most common plumbing calls we get at Radiant. Between Austin’s older limestone homes and San Antonio’s modern builds with high-efficiency systems, water heater issues pop up in every kind of home.
The good news? Not every problem means you need a full replacement. Here’s what might be happening, what you can safely check yourself, and when it’s time to call the certified plumbers at Radiant for water heater repair — backed by the Radiant Guarantee.
Common Water Heater Problems (and What You Can Check First)
Our technicians get hundreds of calls every year from homeowners across Round Rock, Cibolo, and South Austin about the same handful of issues. If your water heater isn’t heating or keeps shutting off, here’s how to pinpoint what’s wrong.
No Hot Water at All
If you’ve got no hot water whatsoever, don’t assume your water heater is done for. In many Austin homes—especially older ones in neighborhoods like Hyde Park or Tarrytown—this can happen after a breaker trips or a pilot light goes out.
What to check:
- Make sure power or gas supply is turned on
- Reset the circuit breaker or fuse
- If you have a gas water heater, relight the pilot following the manufacturer’s guide
When to call: If the pilot won’t stay lit, or your breaker keeps tripping, the problem may lie with a faulty thermostat or heating element. Schedule a water heater inspection and we’ll have a certified Radiant plumber inspect it safely.
Water Not Hot Enough
Homes across Cedar Park and Dripping Springs often call us for this issue: lukewarm water that never quite gets hot enough. It’s commonly caused by a thermostat setting that’s too low, mineral buildup in the tank, or a failing heating element.
What to check:
- Verify that your thermostat is set to about 120°F
- Flush the tank to remove sediment (especially important in hard-water areas like Buda and Kyle)
When to call: If the problem returns after adjustment or flushing, the heating element or thermostat may need replacement.
Hot Water Runs Out Too Fast
If your showers go cold halfway through, you’re not alone—this is a regular complaint in San Antonio suburbs where older tank-style units struggle to keep up with modern usage.
What to check:
- Compare hot water usage (back-to-back showers, dishwasher, and laundry can drain smaller tanks)
When to call: If your tank can’t keep up even with normal use, the dip tube or heating element may be failing, or your system could be undersized for your home’s needs.
Strange Noises or Banging Sounds
We often hear this from homeowners across Greater Austin: “My water heater sounds like it’s about to explode.” Don’t worry—those popping or rumbling sounds usually come from sediment buildup overheating inside the tank.
What to check:
- Drain and flush your tank if you’re familiar with the process
- Listen for grinding or metallic sounds—those can mean loose internal parts
When to call: If noises persist after flushing, call for water heater repair. Ongoing noise can damage your tank and shorten its lifespan.
Leaking Water Heater
A leaking water heater is one of the most urgent repair calls we get—especially in San Antonio’s single-story homes where leaking water can spread quickly.
What to check:
- Tighten drain and temperature-pressure relief valves
- Look for small drips around fittings or at the base of the tank
When to call: If you see standing water, call a plumber immediately. A leaking tank can’t be patched permanently and may need replacement to avoid water damage.
Water Smells or Looks Rusty
If your hot water smells like sulfur or looks rusty, that’s a red flag. Homes with older galvanized pipes—common in East Austin and older San Antonio neighborhoods—see this more often due to corrosion.
What to check:
- Run water for a few minutes to see if it clears
- Smell the water directly from the tap (not from standing water in the sink)
When to call: Persistent odor or discoloration may mean the anode rod has corroded or bacteria is growing inside the tank. A Radiant plumber can replace the rod and sanitize the system.
When to Call a Licensed Plumber
If you’ve checked the basics and the problem keeps coming back, it’s time to call a pro. Electrical issues, gas valve failures, or tank leaks should only be handled by certified technicians.
At Radiant, our licensed plumbers diagnose and repair all makes and models of gas, electric, and tankless water heaters across Austin and San Antonio. And every repair comes with the Home Comfort Guarantee—our promise to fix it right the first time or make it right at no extra cost.
Radiant Repairs Water Heaters the Right Way
When you schedule service, our technician arrives ready to troubleshoot every part of your system—from the heating elements and thermostats to gas valves and safety components.
We start with a complete inspection, run diagnostic tests, and clearly explain your repair options before any work begins. No guesswork, no upselling—just honest recommendations.
If your water heater can be repaired safely, we’ll repair it. If it’s nearing the end of its life, we’ll walk you through your replacement options. Either way, you’ll get a repair that’s backed by our guarantee and performed by one of the most trusted teams for homes across Austin and San Antonio.
For ongoing protection, consider joining the Radiant Care Club, which includes annual water heater tune-ups, priority scheduling, and repair discounts.
