Why is my water heater leaking?
A puddle under your water heater is never something to ignore. In Metro Vancouver and Fraser Valley homes, a leak can range from a simple loose fitting that takes minutes to fix, to a corroded tank that needs full replacement.
The key is finding where the water is actually coming from, because the source determines whether this is a quick repair or a sign the unit has reached the end of its life. Leaks also tend to get worse, not better, so acting early can prevent water damage to floors, drywall, and finished basements.
Here HeatLand explains the most common leak sources, the safe checks you can do yourself, and the warning signs that mean it is time to shut things down and call a licensed technician.
Step One: Find the Source Safely
Before anything, dry the area completely with towels and place fresh paper towel or newspaper underneath the unit. Check back in an hour or two to see where fresh water reappears. Leaks are often mistaken for coming from the tank when they actually originate at a fitting above.
Work from the top down. Inspect the cold-water inlet and hot-water outlet connections at the top, then the temperature-and-pressure (T&P) relief valve and its discharge pipe, then the drain valve near the bottom, and finally the base of the tank itself.
Safety note: if you have a gas water heater and smell gas, or an electric unit with water pooling near electrical components, do not touch it. Turn off the gas or shut the breaker if you can do so safely, keep clear, and call a licensed technician. Water and electricity together are a serious hazard.
Repairable Leaks: Valves and Connections
Many water heater leaks come from parts that can be repaired without replacing the whole unit. Loose inlet or outlet connections can sometimes be gently tightened, or may need new fittings. A dripping drain valve at the bottom may just need to be fully closed, or replaced if worn.
The T&P relief valve is a common source. It is a safety device that releases water if pressure or temperature gets too high, so a leak here can mean the valve is doing its job because of a real pressure problem, or that the valve itself has failed. Either way it needs investigation, not just replacement.
While some of these are DIY-friendly for a confident homeowner, a licensed technician can identify whether a leaking valve is a symptom of a larger pressure or expansion issue in your system, which is common and easy to miss.
When It Is the Tank: Time for Replacement
If the water is coming from the body of the tank itself – typically the bottom – the news is not good. Internal corrosion has eaten through the steel tank, and there is no reliable repair. A tank leak means the water heater needs to be replaced.
This happens as tanks age, usually past the 8 to 12 year mark, especially if the anode rod was never maintained or sediment was allowed to build up. Once the tank wall is compromised, the leak will only worsen and can flood the area.
If you confirm a tank leak, shut off the water supply to the heater and turn off the gas or power. Then call HeatLand. Serving Metro Vancouver and the Fraser Valley since 1999, we can assess the unit, recommend a properly sized replacement, and discuss tank versus tankless options, with financing available.
Quick Checklist
- Dry the area and place paper towel to locate the fresh leak source
- Check top connections, T&P valve, drain valve, then tank base in order
- Tighten a loose drain valve or connection if accessible
- Shut off water supply if the leak is significant
- Turn off gas or breaker before any hands-on work
- Call a licensed technician for tank leaks or any pressure-valve leak
| Leak Location | Likely Cause | Repairable? |
|---|---|---|
| Top connections | Loose or corroded fittings | Usually yes |
| T&P relief valve | High pressure or failed valve | Yes – needs diagnosis |
| Drain valve | Loose or worn valve | Yes |
| Base of tank body | Internal corrosion | No – replace unit |
Frequently Asked Questions
Is a leaking water heater an emergency?
A small drip from a valve is not an emergency but should be addressed soon. Active water flowing from the tank body, or any leak near electrical components or a gas burner, is urgent. Shut off the water and the gas or power, and call for emergency service. Water damage and safety hazards escalate quickly.
Can a leaking water heater be repaired?
It depends on the source. Leaks from valves, fittings, or the drain valve are often repairable. A leak from the tank body itself, caused by internal corrosion, cannot be reliably fixed and means the unit needs replacement. A licensed technician can confirm which situation you have.
How long do water heaters last before they leak?
Conventional hot-water tanks typically last 8 to 12 years, though regular flushing and anode rod maintenance can extend that. Tankless units often last longer with proper maintenance. If your leaking tank is past a decade old, replacement is usually the wiser investment over repair.
What should I do first when I find a leak?
Dry the area to locate the true source, then shut off the cold-water supply valve to the heater to stop water entering the tank. For a gas unit, turn the gas control to off; for electric, switch off the breaker. Then call a licensed technician to diagnose and repair or replace the unit.
Reviewed by the HeatLand Heating & Cooling team — licensed HVAC contractor serving Metro Vancouver & the Fraser Valley since 1999. This article is for general guidance only. If you smell gas, suspect a carbon monoxide leak, or are unsure about any electrical or gas component, stop troubleshooting immediately and call a licensed technician or 911.