Geyser: element, thermostat or plumber? How to tell, and how it gets priced

Two-minute test: whose job is it?

Electrician — the water is cold or lukewarm, the geyser makes popping or crackling noises, your electricity bill has climbed for no reason, or the breaker or earth leakage trips when the geyser heats. All electrical.

Plumber — water is dripping through the ceiling, the overflow pipe outside is running, there is a damp patch spreading above the bathroom, or the tank has burst. That is water, not wiring.

Both — the geyser has to be replaced. By law that needs a registered plumber and a registered electrician. Doing it yourself, or letting a handyman do it, voids your insurance and the warranty.

Element or thermostat? They fail differently

The element is the heater sitting in the water. It is a wire inside a metal sheath, and it fails from sediment, hard water and simple age. When it goes, you get no hot water at all, or it takes forever and never gets properly hot. A cracked element also leaks current to earth, which is why a dying geyser is one of the most common reasons an earth leakage unit starts tripping. More on that here.

The thermostat is the switch that decides when to heat. When it fails you get water that is too hot, water that is never hot enough, or a temperature that changes from one shower to the next. Thermostats also have a safety cut-out that trips when things get too hot — and if that keeps tripping, the element is often the real culprit.

Because the two sit together and the geyser has to be drained either way, replacing both at once is often the sensible call. The extra part is small; the second visit is not.

What sets the price is the part itself, whether the geyser has to be drained and refilled, and how hard it is to reach. A geyser wedged in a roof space over a passage is not the same job as one standing in a garage. You get the price in writing before I start, and there is no magic in the mark-up.

How long an element should last

Three to five years is normal in South African conditions, and hard water shortens it. If yours went at two years, something else is going on — usually sediment build-up, or a thermostat holding the water hotter than it needs to be. If yours lasted eight, count yourself lucky and change it before winter rather than during it.

The symptoms people describe to me, almost word for word: water not reaching the set temperature, the temperature never staying the same, popping or crackling from the roof, a bill that jumped, and the board tripping. Any of those is worth a phone call before you are showering with a kettle.

When it is not worth repairing

Replacing a whole geyser costs several times what an element costs, and it needs a plumber as well as me. If your geyser is old, has been repaired more than once and shows rust at the fittings, putting another element into it is throwing good money after bad. I will tell you that, even though fitting the element is the easier money.

Insurance is the other half of that decision. Insurers generally cover a sudden burst but exclude gradual leaks and ordinary wear, usually require the work to be done by a registered person with the certificate to prove it, apply an excess, and often decline geysers over fifteen years old. So a very old geyser is a risk you are carrying yourself whether you realise it or not.