Start at the breaker panel. Electric water heaters run on a dedicated double-pole breaker, and a tripped breaker looks exactly like a dead heater. Reset it once. If it trips again, stop and call — a repeatedly tripping breaker means a shorted element or wiring fault, not a fluke.
On electric units, look for a red reset button behind the upper access panel. That is the high-limit switch, and it trips when tank temperature runs away. Press it once. Again, if it trips a second time, something upstream is wrong.
On a gas unit, look through the viewport for the pilot flame. If it is out, follow the relighting instructions printed on the unit exactly. A pilot that lights and dies within a minute is usually a failing thermocouple — an inexpensive, common repair.
Check the thermostat setting has not been knocked down, and confirm the gas or water shutoff valve is fully open — this catches more calls than you would think after any other work in the house.
Anything involving water on the floor, a hissing T&P valve, a gas smell, or a breaker that will not stay set: stop and call us. Those are not DIY items and they do not get better with time.
