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Water Heater Advisor
Do this first

Leaking tank or no hot water

If water is actively leaking, do these three things before you read anything else or call anyone. They take about two minutes and they stop a bad day becoming an expensive one.

  1. 1.Turn off the water to the heater

    There is a valve on the cold inlet pipe at the top of the unit. Turn it clockwise until it stops. If you cannot find it or it will not move, shut off the main water supply to the house.

  2. 2.If it is gas, turn the gas control to off

    The dial or switch is on the control box near the bottom of the tank. If you smell gas at any point, do not touch anything electrical. Leave the house and call your gas utility from outside.

  3. 3.If it is electric, switch off its breaker

    Find the breaker labelled for the water heater and switch it off. An electric element left powered in a drained tank will burn out within minutes, which turns a leak into a bigger repair.

The first decision

Can it be repaired, or does it need replacing?

Worth two minutes even in an emergency, because the answer is usually clearer than people expect and getting it wrong is expensive in both directions.

Often repairable
  • No hot water but the tank itself is dry
  • Pilot will not stay lit on an otherwise sound unit
  • A single failed heating element or thermostat
  • Leaking from a fitting or valve rather than the tank body
  • The unit is under about eight years old
Replace it
  • Water is coming from the tank body itself
  • Rusty or discoloured hot water
  • The unit is past about twelve years old
  • You have already paid for a repair in the last two years
  • The repair quote is more than about half a replacement
Find the source before you decide

Three of these four are parts. The fourth is the tank. From a puddle on the floor they look identical, so dry everything you can reach, lay paper or a towel under the unit, and come back in an hour — whatever is wet again is your answer.

  1. Cold inlet or hot outlet

    Often repairable

    The threaded connections on top. These can be resealed or replaced without touching the tank.

  2. T&P valve or its discharge pipe

    Often repairable

    Worth saying: sometimes this valve is not broken. It is relieving pressure because something else is wrong, and that is a different repair — not a new heater.

  3. Drain valve near the floor

    Often repairable

    A common failure and among the cheapest. Easy to mistake for the tank, because the water lands in the same place.

  4. From under the tank, with every fitting dry

    Replace it

    The tank has rusted through from the inside. This is corrosion rather than a part, and there is nothing to tighten or swap.

Drawn as a gas unit because it is the most common. An electric tank has the same four points and no flue. On a gas unit, water can also be condensation rather than a leak — it shows up during long heating cycles and stops once the tank is up to temperature.

The second decision

Same again, or the upgrade you were considering anyway?

This is the moment most homeowners get pushed into a decision by circumstance. It is worth knowing which options are realistically on the table today and which are not.

What we ruled out for your home

  • Tank to tankless conversion, today. Realistically not a same-day job. Permits, venting, often gas and electrical work, sometimes a second trade. Worth planning properly, not deciding on while the family has no hot water.

  • Heat pump, today. Same problem. It may well be the right long-term answer for your home, and utility rebates can be substantial, but it needs electrical capacity checked and a condensate route planned.

What that leaves

For most people with a dead heater, a like for like replacement is the honest answer. It is fastest, it is cheapest, and it does not force a multi-thousand dollar decision under pressure.

There are two exceptions worth knowing about. If your unit sits in a garage or utility room with room around it, a heat pump can sometimes be fitted nearly as quickly as a tank and may attract a rebate that changes the maths considerably. And if you were already planning to convert within the year, doing it now saves paying for installation twice.

Ask your contractor both questions directly. A good one will give you a straight answer about what is achievable today.

While you wait

Two minutes that make the next conversation shorter

Our questions shorten automatically when you tell us the heater has already failed. You get a recommendation, a realistic cost range and the questions to ask, which is a much better position to be in when a contractor is standing in your garage.

Start the short versionHow to check a contractor

We are not a plumbing company and we do not perform installations. We help you work out what you need, then introduce you to a licensed local contractor who does that work.