ResidentialHot water
What to Do About a Leaking Water Heater
A puddle beside the water heater is worth ten minutes of calm checking. Some leaks are a loose fitting. Others mean the tank is finished.
Spacious kitchen under renovation with ladder and tools, showcasing a fresh new design.
- Tank, burner, anode and relief valve checked in order
- Venting and drain pan looked at, not just the thermostat
- Repair-or-replace laid out with the reasons
- Hot water tested at the tap before we leave
- Licensing details confirmed when you call
- Residential
- Commercial
- Markham & York Region
How the job runs
- For a gas tank, turn the control knob to Pilot or Off. For an electric tank, switch off its breaker.
- Shut the valve on the cold inlet pipe above the heater.
- Put down towels and move anything stored nearby.
- If the leak is heavy, run a hose from the bottom drain valve to the floor drain.
What's included on this job
What we open
The drain valve, the relief valve outlet, and the cold and hot connections on top of the tank.
What we bring
Moisture meter, adjustable wrenches, a hose to drain the tank, and towels and a wet vac for the floor.
What we replace
A leaking drain valve, a relief valve that weeps, or connectors at the top. A leak from the shell means a new tank.
How we prove it
Tank refilled, burner relit, and the base and connections checked dry after the first heat cycle.
Signs you need this
- A puddle ringing the tank base
- The T&P discharge tube dripping
- Rust streaks down the jacket
- Damp drywall beside the heater
Where is the water coming from?
| Location | Likely cause | Usually |
|---|---|---|
| Top connections | Loose or corroded fitting | Repairable |
| Relief valve pipe | High pressure or temperature, or a worn valve | Repairable |
| Drain valve at the base | Worn washer or plastic valve | Repairable |
| Under the tank, from the body | Corroded inner tank | Replace |
Why tanks leak in Markham basements
Every tank has an inner steel shell protected by a glass lining and a sacrificial anode rod. Once the anode is used up, the steel starts to rust from inside. Sediment from the city supply sits at the bottom and speeds things up. Where a PRV or check valve closes the supply off from the street, a missing or failed expansion tank can push the relief valve to drip every time the burner runs.
How we handle the job
We dry the area, find the exact source and show you. A fitting or valve leak can often be fixed on the spot. If the tank body is leaking, we talk through replacement, including whether you own or rent the heater. Rental units are normally the rental company's responsibility, so we help you confirm that first.
From the van: A relief valve that drips now and then is not something to cap or plug. It is a safety device doing its job, and the cause needs to be found.
If the water comes from the steel shell itself, no part will fix it. That tank is done.
What changes the cost
A fitting or valve fix is a short visit. A full replacement depends on tank size, venting and access. Water damage to flooring or drywall is separate and may be covered by home insurance.
Call before it gets worse
Small tank leaks rarely stay small. The steel only gets thinner.