Water Heater Services

It depends what failed and how old the tank is. Thermocouples, gas control valves, heating elements, thermostats and drain valves are all repairs, and on a tank under about eight years old with a sound shell they are usually worth doing. A tank leaking from the shell itself has corroded through from the inside and cannot be sealed. Ask the plumber where the water is coming from: a fitting is fixable, the tank is not, and they should be willing to show you.

Sediment. Minerals that came out of solution as the water heated have settled into a layer on the tank bottom, and water trapped underneath turns to steam and forces its way up through it. In a gas heater that layer sits between the burner and the water, so the burner drives heat through an insulating crust and overheats the tank bottom. Flushing clears it while it is still loose; left for years it bakes hard and flushing will not shift it.

Annually is the sensible default, and more diligently in hard-water areas. Hardness varies enormously between cities and even between neighbourhoods on different supplies, so the right interval follows your local water rather than a generic schedule. Keep to it rather than waiting for symptoms, because loose sediment flushes out easily and hardened scale does not.

It depends on your hot water pattern and what the installation involves. Tankless units heat on demand, so there is no standby loss and no tank to fail, and they last longer. The catch is the install: they often need a larger gas line, different venting and sometimes electrical work, which is where the cost sits. In hard water they also need descaling on a schedule or the heat exchanger scales up. Ask for the whole install to be priced, not just the unit.