No Hot Water? Diagnose the Likely Cause

Waking up to cold water is never fun. Most no-hot-water cases fall into a handful of common causes. Here's how to diagnose from the simplest check up to the one that needs a plumber.

No Hot Water? Diagnose the Likely Cause

Check power and the reset button

For an electric unit, make sure the breaker hasn't tripped and press the reset button on the thermostat. This fixes a surprising number of 'no hot water' cases and costs nothing.

Check the pilot light (gas)

For a gas storage unit, check the pilot light is lit. If it's out, follow the manufacturer's relight instructions (or call a gas fitter). A gas unit that won't stay lit usually has a thermostat or thermocouple issue.

Check the thermostat and element

If the unit gets power but only warms slightly, the thermostat or heating element may have failed. These are replaceable parts, but they need a licensed plumber.

When to call a pro

If the unit is leaking, making strange noises, is very old, or none of the simple checks help, it's time for a plumber. They'll test the element, thermostat and tank, and tell you whether a repair or replacement is the smarter call.

Common questions

Why did my hot water suddenly stop?

Most commonly a tripped breaker, a blown element, a failed thermostat, or (for gas) a pilot light issue. It may also be the tank itself.

Can I replace a heating element myself?

It involves draining the tank and accessing electrical parts — best left to a licensed plumber for safety and code compliance.

Reset button keeps tripping — what now?

A reset that keeps tripping usually means a failing element or thermostat. Book a plumber to test and replace the faulty part.

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