The thermostat is your water heater's brain — and when it fails, the symptoms are unmistakable: scalding water that could burn a child, endless lukewarm showers, or a unit that runs constantly and drives up the electric bill. Electric tanks have two thermostats (upper and lower) that must work in sequence; gas units regulate through the gas control valve's thermostat.
A failed thermostat isn't just inconvenient — an overheating tank stresses the TPR valve and every seal in the system, which is how thermostat failures turn into leaks. We test both thermostats under load, replace the faulty one with an OEM-grade part, and calibrate to a safe 120°F unless you request otherwise.
Active leak, no hot water, or gas smell — don't wait. Call Emergency Line
Test under load: both thermostats checked with the tank at temperature.
Replace: faulty thermostat swapped for OEM-grade parts; wiring inspected for heat damage.
Calibrate: set to a safe 120°F and verified with a thermometer at the tap.
Storm-season note: power surges are the leading killer of electric thermostats in DeSoto. If your hot water went haywire after an outage, the thermostat is suspect number one — and a quick test beats guessing.
| Service | Typical Range |
|---|---|
| Thermostat diagnosis / service call | $89–$149 |
| Thermostat replacement | $200–$350 |
| Thermostat + element combo | $200–$450 |
Ranges are representative market estimates for the DeSoto area and can vary by unit size, access, and parts. Final pricing is confirmed on-site before any work begins. Owner to verify.
Yes — water above 140°F can cause third-degree burns in seconds, especially for kids and seniors. A runaway thermostat is urgent.
Surges can damage thermostat contacts or trip the high-limit reset. We see a spike in thermostat calls in the week after major storms.
Rarely. 120°F is the safe, efficient standard. Higher settings waste energy, accelerate tank wear, and raise scald risk.
Gas units use an integrated gas control valve with thermostat function — we service and replace those as a unit.
We also serve Cedar Hill, TX, Duncanville, TX, Lancaster, TX, Glenn Heights, TX, Red Oak, TX, Ovilla, TX and all surrounding areas. Back to the DeSoto water heater leak repair homepage.
Water too hot, too cold, or inconsistent in DeSoto, TX? Faulty water heater thermostats replaced & calibrated. One call gets you a real dispatcher and upfront pricing.
Call (833) 713-2101