Leaking water heater: what causes it & how to fix it?

Is there a damp patch near your geyser and you’re worried about a leaking water heater? You’re not alone. A small leak can quickly escalate, leaving you with musty smells, higher bills, and even serious water damage. In this article, we’ll help you identify if your water heater leak is the real culprit, explain why it happens, and show you exactly how to fix it.

Common causes of a leaking water heater

• Corrosion in the tank: Over time, water heater corrosion can develop inside the tank, creating rust spots that weaken the steel walls. Eventually, these rust patches give way, causing small leaks or even bursts.
• Loose or failing connections: Inlet and outlet pipes can loosen over the years, especially around the joints. If you notice moisture around these areas, you might just need to tighten them.
• Damaged temperature & pressure (T&P) valve: This safety component releases water when pressure becomes too high. A faulty T&P valve might leak occasionally or constantly if it’s old or clogged.
• Worn-out drain valve: The drain valve at the bottom of your geyser can corrode and fail. If it’s not tightly closed or the washer is worn, expect annoying drips.
• Ageing geyser: Most units have a lifespan of 8–12 years. As parts weaken over time, you may see rust in your hot water or a slow, persistent leak.

Ignoring these potential causes can lead to more than just a damp floor. Stay alert, because failing to fix the root issue may result in serious home damage and higher energy bills.

What happens if you ignore your water heater leak

• Higher utility costs: A weakened tank uses more energy to heat water. You’ll end up paying for wasted energy without even realising it.
• Structural damage: Ongoing leaks seep into floors, walls, and adjacent rooms, weakening building materials and encouraging mould growth.
• Loss of hot water supply: If the water heater finally fails, you could be stuck without hot water at the worst possible time.
• Premature replacement: Continuing to let corrosion or leaks worsen may mean you have to replace the entire unit sooner.

Best ways to fix a leaking water heater

1. Quick DIY checks

Before you roll up your sleeves, switch off the geyser’s power at the mains (or turn off the gas supply). Then:

1. Check all connections: Tighten any loose nuts on the inlet, outlet, and pressure relief valve with an adjustable wrench.
2. Assess the drain valve: Ensure it’s snugly closed. If water still drips, the washer might need replacing.
3. Inspect the T&P valve: If it’s leaking, gently raise and lower the test lever to clear any debris.

If there’s still dripping or rust-coloured water, you may need a structural fix or servicing.

2. Temporary DIY fixes

If the leak is small and you’re waiting for professional help, try these stopgap measures:

1. Pipe sealant: For minor pipe or valve leaks, shut off water flow and apply a high-quality plumber’s tape or liquid sealant. Handle any hot surfaces carefully.
2. Rust converter paint: This special coat can slow down corrosion on a rusty tank. Clear off debris first, then brush on the product to inhibit further rust.

Bear in mind that these fixes only buy you time. If the tank is severely corroded, or connections are heavily damaged, you’ll need a more permanent solution.

Geyser repairs can be complex, so consider calling in a professional sooner rather than later to avoid future trouble.

3. Professional solutions

When basic fixes aren’t enough, specific steps like draining the tank, replacing corroded sections, or even installing a new unit may be required. A pro will:

1. Assess the tank’s condition: They’ll open and inspect for deeper hazards like advanced rust and failing components.
2. Drain and clean the geyser: Draining removes sediment that promotes corrosion, while a thorough rinse keeps the system efficient.
3. Repair or replace damaged parts: Valves, washers, or segments of pipe can be switched out to extend your geyser’s life.
4. Install a new water heater (if needed): If your rusty tank is beyond repair, a fresh install provides a longer lifespan and better efficiency.

When to call a professional

• Excessive rust or cracks in your water heater tank
• Persistent leaks you can’t locate or fix
• Inconsistent water temperatures or discoloured water
• Concerns about hefty repair vs. replacement costs

Remember, qualified plumbers or geyser services bring specialised equipment and knowledge to troubleshoot water heater corrosion and restore hot water fast.

For a bonus tip, consider installing a drip tray under your tank to catch small leaks: it’s a simple and affordable way to protect your floors in the future. If you’re looking for professional help, submit a free request on procompare.co.za and let local experts tackle your leaking water heater effectively.