Water Heater Repair in O'Fallon, MO
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St. Charles County winters put your water heater to work
Incoming water runs colder from October through April, and your water heater has to work harder those seven months to bring it up to temperature. Longer burner cycles and more recovery time between showers put more wear on the thermostat and the burner assembly than the rest of the year does.
Power is the other piece. Missouri saw 19% of households lose power for at least a day in 2024, and this county has logged 9 winter storms and 84 damaging wind events over the last ten years. A gas water heater with a standing pilot keeps running through an outage. One with electronic ignition will not relight on its own once power is back. If your water heater has been cold since the lights came on, that is usually why.
- 25°F
- the average winter night, and colder incoming water means longer heating
- 7 months
- October through April, the months homes here need heat
- 19%
- of Missouri households lost power for a day or more in 2024, and a heater with an electric element or electric ignition stops without it
NOAA nClimDiv, 1991–2020 normals
A new water heater would cut about $80 a year off hot water for a typical Missouri home.
Estimates for a typical Missouri home, compared with an older unit built to the federal minimum, from EIA household energy data and Missouri fuel prices. Your home will differ.
Repair makes sense when an element, thermostat or gas valve has failed.
Replacement makes sense when the tank itself is leaking.
- Why is my water heater leaking from the bottom?
- The tank itself has likely rusted through from the inside and is starting to fail. Water heaters corrode from the inside over years, and once the tank wall gives way, the leak will only get worse. It could also be the drain valve or a fitting that has loosened, which a contractor can check before assuming the tank is done. If the leak is coming from the tank itself, the water heater needs to be replaced, not repaired.
- Why won't the pilot light on my water heater stay lit?
- The most common cause is a worn thermocouple, the small part that senses the pilot flame and tells the gas valve to stay open. When it wears out, it fails to sense the flame properly and shuts the gas off even though the pilot is lit. A dirty pilot orifice or a draft blowing out the flame can cause the same problem. A contractor can test the thermocouple and replace it if that is the cause.
- Can a tankless water heater be repaired?
- Yes, most tankless water heater problems can be repaired without replacing the whole unit. Common issues include a clogged inlet filter, mineral scale buildup on the heat exchanger, a failed igniter, or an error code pointing to a sensor problem. A contractor can diagnose which part is causing the issue and repair or replace just that part in most cases.