Elements and thermostats
The two most common causes of no hot water and of lukewarm water, and the cheapest things on this list to fix.
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Geyser repair in Durban usually turns on one question: is the cylinder sound? If it is, an element, a thermostat or a valve is a repair. If it is not, you need a replacement and a certificate, and we will say so plainly.
Describe what the hot water is doing, and give us the brand if there is a badge on the cylinder. If you can reach the date stamp on the cylinder that helps a great deal, because it tells us whether a warranty is still live before anybody quotes.
Most geyser faults are a part, not a cylinder. The ones that are not get said out loud rather than quietly upsold.
The two most common causes of no hot water and of lukewarm water, and the cheapest things on this list to fix.
The safety valve that weeps when pressure is wrong. Replaced after the cause is measured, not instead of measuring it.
The small vents that protect a geyser when a main empties. On a rationed network they matter and they fail quietly.
Inlets, outlets and the drip tray arrangement. A tray that cannot drain turns a small weep into a ceiling problem.
Pumps, controllers, sensors and refrigerant loss, which are ordinary repairs mistaken for whole system failures.
An itemised, correctly dated invoice describing the failed part, because that is what an insurer assesses on.
The usual explanation offered for geyser failure in South Africa is scale, and in Durban that is mostly a distraction. The supply here is treated surface water from the Umgeni system, and the thing wearing your geyser out is not what is dissolved in it. It is what happens to the geyser when the water stops and starts.
eThekwini has rationed supply since the April 2022 floods destroyed two of four aqueducts at Molweni and cost Durban Heights around 280 megalitres a day. Rationing means published windows of no supply, and reservoir inlets held part open, so a very large number of properties drain down and refill on a daily cycle. The City is straightforward about the reason: rationing is done to build storage, and water is reopened when levels allow.
A geyser is the worst placed thing in the house for that. It is a sealed vessel at the top of the building, so it is the last thing to refill and the first thing to be affected when the column of water above it disappears. Its vacuum breakers exist precisely to let air in when a main empties, so the cylinder is not pulled inwards. When the water comes back, that air has to leave, and it leaves through the geyser's connections, carrying whatever grit the refill scoured off the pipe walls with it.
And crucially, none of that has to break anything on the day. A seal takes the shock and holds. A seam loses a little of its protective layer. The element seat is disturbed by a fraction. The geyser works perfectly that evening and for the next four days, and then starts weeping. By the time anybody notices, the outage is a week ago and nobody connects the two, so the failure gets written off as bad luck or old age.
The habit that prevents most of this costs nothing: switch the geyser off at the board when supply goes off, and leave it off until the taps run properly again. An energised element in a draining tank burns out fast and can crack its housing. Beyond that, the two things worth having checked on a rationed zone are whether the vacuum breakers still vent and what the incoming pressure actually is, because those are the geyser's only defences and both fail silently.
Five checks that decide repair against replace, done in that order.
Repair first where repair is honest, and a clear reason when it is not.
If the cylinder is still under its manufacturer warranty you should be claiming it, not buying a new one from us.
A weeping valve gets the pressure measured. Replacing the part without finding the cause means doing it again.
Where both are genuinely possible you get the repair figure and the replacement figure and you choose.
Access damage is the installer's problem to avoid and to make good, not a line that appears on your invoice.
Cost first, then the repair against replace decision, which is where the money actually is.
Repairs sit at the bottom of the range, and that is precisely the reason to settle the diagnosis first. Once a conversation has moved on to replacing the cylinder, the numbers change entirely. An element or a thermostat is a part plus roughly an hour, against the trade's published national guidance of R450 to R850 an hour and a R450 to R650 call-out, both excluding VAT. A replacement geyser is an order of magnitude more. You are told which of the two you are looking at, and why, before a price is put on anything.
The cylinder decides that, not the number of years on the label. Where the cylinder itself is intact, more or less everything else on a geyser is a serviceable part. Elements, thermostats, safety valves and overflow arrangements all come off and go back on, and the unit carries on working for years afterwards. If the cylinder itself is weeping at a seam or has corroded through, no repair is honest and you need a replacement with a certificate. A geyser being twelve years old is not by itself a reason to condemn it, and being four years old is not a guarantee that it is fine.
Almost certainly not, and the delay is what throws people. A geyser that has sat part empty during a rationing window takes the refill through its cold inlet, its vacuum breakers and the element seat all at once, with air ahead of the water and a pressure spike as the void closes. Nothing has to fail at that instant. A seal that absorbed the shock can start weeping days later, and a seam that lost its protective layer can seep well after. The event that caused it and the day you noticed it are rarely the same day.
It is the geyser reporting something and it should not be ignored, though it is not usually an emergency. When that valve drips it is frequently not faulty at all. It is venting, because the pressure reaching it is higher than it was ever meant to see, so fitting a new one treats the wrong thing and you will be watching the replacement drip before long. The right order is to measure the incoming pressure first and deal with the pressure if that is the cause. The other common reason is grit under the seat, which on a network that scours its pipes on every refill is not rare.
Usually one of three things, and they are distinguishable. A thermostat that has drifted low or failed will hold the water at a steady but disappointing temperature. An element that has partly burnt out heats, but cannot keep up with demand, so you get hot water that runs out unusually fast. Or the geyser is being fed cold water at the top of the tank through a failed one-way arrangement, which mixes the stored hot water down. A test at the element and a temperature reading at the outlet separates them inside half an hour.
A burst cylinder and the water damage it causes sit inside most household policies written in this country, so lodge the claim before you commit to anything. Two things will be asked for: an itemised invoice showing what was done and when, and where a new geyser goes in, a valid Certificate of Compliance. Make sure whoever does the work agrees to produce both before they start, and check the plumber's registration number yourself at pirb.co.za, because a certificate from someone whose registration has lapsed is not one.
Yes, and this is the single most useful habit in a rationed supply area. An element that is energised while the tank is emptying can be left running dry, which destroys it quickly and can crack the element housing. When a published outage window is coming, switch the geyser off at the distribution board and leave it off until you are certain the supply is back and the tank has refilled. Then switch it on. It costs nothing and it prevents the most avoidable geyser failure there is.
Yes, and the fault is usually not where people assume it is. On solar systems the panels themselves rarely fail; the circulation pump, the controller or the temperature sensors do, and those are ordinary parts. On heat pumps the common failures are the fan, the reversing valve and refrigerant loss, and a heat pump that has lost its charge will still run while heating almost nothing, which is why the bill goes up before anybody notices it is broken.
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Tell us what the geyser is doing and roughly how old it is, and you will get a view on repair against replacement before anyone comes out.