Water heater calls here are steady all year rather than clustered in winter, and that tells you something about why they fail.
Age, not weather
A great deal of North Charleston housing stock was renovated or built out in a similar window, so original heaters reach end of life on a similar timetable. Tanks fail because they are twelve years old, not because it got cold.
What is worth repairing
A thermostat, element, thermocouple or gas valve on a tank under eight years old is generally worth fixing. A tank leaking from the body is not — that is the tank itself and no repair addresses it. Between those, the anode rod and the amount of sediment decide it. We will give you the arithmetic rather than default to selling a replacement.
Rental properties
If you manage tenanted property here, a failed water heater is an occupied-unit emergency. Replacing a marginal twelve-year-old tank on your schedule is considerably cheaper than replacing it at 9pm along with the flooring underneath it.
Worth doing while we are there
Flushing sediment, checking the anode rod, and testing the expansion tank and T&P valve. On an older tank these are the difference between a few more good years and a failure you did not see coming.