Water Heater Not Working? Here's What to Check Before Calling a Plumber

Waking up to a cold shower is one of the most universally frustrating experiences in homeownership. But before calling a plumber, it's worth checking a few things — some issues are quick DIY fixes, while others need a professional right away.

Step 1: Check If It's a Gas or Electric Heater

The troubleshooting path is different depending on your heater type. Most GTA homes have either a natural gas tank-style heater or an electric heater. Check your unit — there will be a label or a visible gas line/electrical connection.

For Gas Water Heaters

Pilot Light Out

Older gas water heaters have a pilot light that can blow out. Look through the small viewing window near the base of the tank. If the flame is out, follow the relighting instructions printed on the heater label. If it won't stay lit, the thermocouple may be faulty.

Gas Supply Issue

Check that your gas supply valve (the lever on the gas line feeding the heater) is fully open — parallel to the pipe means open, perpendicular means closed. Also verify your other gas appliances (stove, furnace) are working. If nothing gas-powered works, call your gas utility.

Smell Gas? Stop Everything.

If you smell gas near the water heater, do not attempt to relight anything. Leave the house, leave the door open, and call your gas utility and a licensed plumber immediately.

For Electric Water Heaters

Tripped Breaker

An electric water heater draws significant power. Check your electrical panel for a tripped breaker labelled "water heater" or "HWT." Reset it once — if it trips again immediately, there's a wiring or element fault.

Reset Button Tripped

Most electric water heaters have a red reset button on the upper thermostat, accessible by removing the access panel. Press it firmly. If it trips again, you likely have a faulty thermostat or heating element.

Common Problems That Need a Plumber

Leaking Tank

Water pooling around the base of a tank water heater almost always means the tank itself has corroded and is leaking internally. This is not repairable — the tank needs to be replaced. A typical tank lasts 8–12 years in the GTA's hard water conditions.

Discoloured or Rusty Water

Rusty or brown hot water usually means the anode rod inside the tank has failed and the tank is corroding. This is a sign the heater is near end of life.

Popping or Rumbling Sounds

Loud banging or rumbling from the tank is caused by sediment buildup on the heating element or burner. A flush might temporarily help, but if the tank is old, replacement is the better investment.

Lukewarm Water Only

If you're getting warm but never fully hot water, the thermostat setting may be too low (recommended: 49°C / 120°F) or a heating element may have partially failed.

Repair vs. Replace: The GTA Rule of Thumb

If your tank is under 7 years old and the repair cost is under $500, repairing usually makes sense. If the tank is over 10 years old or the repair approaches the cost of a new unit, replacement is almost always the smarter move — especially with energy-efficient options now available.

Proper Plumbing GTA installs and repairs water heaters across the GTA — same-day service available. Call 647 206 3327