Zaid Petersen on fitting a geyser blanket and timer before spending more on hot water

A geyser blanket and timer in Cape Town homes can fit is the cheap fixes first move. Got an older geyser? You're likely weighing up a blanket, a timer, a heat pump or solar.

Interview by Tomek Korzeniewski · with Zaid Petersen, Owner and master plumber

What actually decides if a blanket and timer are worth fitting

The right fix depends on your house, the people in it and how long you plan to stay. Sometimes the smart move is a blanket and a timer. He tells people that even when a bigger job would earn him more.

He won't sell someone a heat pump or a solar system that doesn't make sense for them. That honesty runs through how he weighs up any home. A retired couple out all day needs something different. A house of five taking showers morning and night needs something else entirely.

So the starting point is your own situation, not the product. Once you know how many people use the water and how long you're staying, the choice gets simple. Cheap fixes first, before anyone talks about spending real money. So what does a blanket actually do once the tank is hot and just sitting there?

What a geyser blanket does to standing heat loss

It slows down standing heat loss.

A decent blanket on the tank, plus lagging on the first couple of metres of hot pipe, cuts that loss. He calls it a morning's job. It won't change your life, he says but it's the first thing he'd do in any house.

Worth knowing: a blanket only helps between uses, keeping the hot water hot for longer. It does nothing about when the geyser switches on in the first place. Sorting that out saves you far more than the blanket ever will.

How a timer matches hot water to your routine

So a timer is the fix. It means the element only runs when you tell it to. Petersen points out that most families use hot water in the morning and the evening. There's no sense heating it at two in the afternoon when the house sits empty.

He sets the timer to switch on an hour or two before people wake up, then again before the evening showers. The catch is being honest about your routine. Teenagers who shower at random times can leave someone standing under a cold tap. Then he adjusts the settings.

The one he fits has a manual override button, so you can force a heat-up when the day goes off-plan. A timer works best on a healthy geyser with steady demand. When a household starts using a lot more hot water, that's when the question changes.

When a heat pump earns its keep instead

A heat pump earns its keep when a household uses a lot of hot water every day. Petersen describes it as a small air conditioner in reverse. It pulls heat from the outside air into the water. And it uses a fraction of the electricity an element does for the same hot water.

Lots of showers, a bath, washing up by hand. It also suits a home where the geyser is healthy with years left. A heat pump works with the tank you already have. They plumb it in alongside.

One thing to watch: it's the wrong move for one retired person having a quick morning shower. It takes a very long time to earn back. It's also wrong when the geyser is on its last legs. Petersen puts it plainly: a new heat pump on a rusty tank is like new tyres on a car with no brakes. Sort the geyser first. A once-a-year Geyser Health Check is a sensible starting point before you choose anything. It finds the problem before it comes through your ceiling. A once-off check-up through geyser servicing Cape Town lets you see the tank's condition before you spend a cent on a heat pump. For wider background, see gov.za.

Why placement and salt air matter in Cape Town

Where a heat pump sits matters as much as whether you buy one. Petersen says it has a fan and a compressor, so it makes a hum. Roughly like a fridge, not loud. But you don't want it under a bedroom window or hard against the neighbour's wall.

He looks for a spot outside with airflow, close to the geyser so the pipe runs stay short. Short pipes lose less heat on the way. In Kalk Bay and Simon's Town, on narrow plots pressed against the mountain, finding that spot takes some thought.

Salt air makes a real difference too. Petersen warns that salt eats aluminium fins. Near the beach you want a coastal-rated unit with coated fins, rinsed with fresh water every few months. The same sky and roof questions decide the other option worth weighing up, solar.

Solar geysers, backup power and load-shedding

There are two main kinds of solar geyser. Petersen breaks it into flat-plate panels and evacuated tubes. Both sit on the roof to heat water with the sun. Then there's the split between direct systems, where the household water runs through the panel and indirect ones, with a separate antifreeze loop carrying the heat. On the Noordhoek and Kommetjie side it gets cold on clear winter nights. So he leans towards indirect systems there.

Solar needs the right roof. A north-facing roof with no big trees or mountain shadow in the middle of the day is what he's after. Parts of Kalk Bay, St James and the upper side of Fish Hoek lose the sun early in winter. The mountain stands right behind them. Tokai and Constantia have beautiful old oaks that shade half a roof. So he goes up and looks before he quotes.

Solar also holds up in a power cut. Petersen says a solar geyser keeps heating while the power is off, as long as the sun is out. A heat pump stops when the power stops. Same as an element. He adds one caution: if you run a battery backup for the house, don't put the heat pump or the element on it. Hot water is a big load. Better to heat while the grid is on and keep the battery for lights, the fridge and the internet.

Four questions that match the fix to the house

Picking the fix starts with four questions. The answers point to the right fix before anyone quotes a rand.

Then he lays the options out on one page: blanket and timer, heat pump, solar, with what each one involves. People choose better when they see all three side by side. He remembers a couple in Bergvliet who wanted a heat pump because their neighbours had one.

Two people, out most of the day, a small geyser in good shape. He told them to try a blanket and a timer for three months first. They called back to say it was enough and that was fine by him. But whichever fix you land on, it still needs a bit of looking after to keep working.

What upkeep each option still needs

How much upkeep? It depends on the fix. Heat pumps ask for more: the filter on the water inlet cleaned, the fins kept clean and a proper service once a year.

Solar panels want a wash when they get dusty or salted, a check of the fluid in an indirect system every couple of years and a look at the valves. So the running cost of a system isn't only what it saves. It's what it asks of you to keep saving.

Whatever you choose still sits on top of the same tank. Start with the cheap fixes. Get someone honest to look at your roof and your geyser and the bigger decision gets easier.

Ready When You Are

For more on this, see Geyser. If you would like to take this further, Geyser servicing is the place to start.

About the expert

Zaid Petersen, Owner and master plumber, Klipspringer Plumbing.

Frequently asked questions

How much does a geyser timer cost to install in South Africa?

The price moves with the type of timer, the geyser's wiring and whether the electrics behind it are up to standard. An older house sometimes needs extra work to fit a timer safely and that changes the job. The only way to get a real number is to have someone look at your geyser and wiring in person.

Is a geyser blanket worth fitting?

For most older geysers, yes. It cuts standing heat loss between uses and it's a small, cheap job compared to swapping out a whole system. Where it makes less sense is on a geyser that's already failing, since no amount of insulation fixes a rusty tank or a dying element.

What is the best geyser timer to look for in South Africa?

Look for one with a manual override button, so you can force a heat-up when your routine changes for the day. Beyond that, match the timer to your household's actual pattern of use rather than chasing a brand name. A timer that fights your routine ends up switched off or bypassed within a month.

Is it worth putting a timer on your geyser?

It's worth it when your household has a fairly steady routine, morning and evening use with quiet hours in between. It's less useful in a home where people come and go at random hours, since the timer keeps missing the moments hot water is actually needed. Households with irregular routines are exactly where the question shifts to other options.

Could you end up with an inflated bill for work that doesn't even fix the problem?

That fear usually comes from a quote given over the phone before anyone's actually seen the geyser. Ask for a proper look at the tank, the element and the wiring before any price is fixed and get that price confirmed before work starts. A written quote that matches the final invoice is what protects you.

Will you be overcharged for something as small as fitting a blanket or a timer?

A small job should come with a small, clear price you can ask us for upfront'. Ask for the price in writing before the work starts, whatever the job size. If a plumber won't put a number down until after the job is done, that's worth questioning.

Will the plumber turn up when they say they will?

That's a fair thing to ask any plumber before you book, not just one doing a small fitting job. A firm should give you a set time, not a four-hour window that leaves you waiting around all morning.

Will the job get rushed because the next one's already booked in?

A blanket and timer job is quick by nature, so rushing isn't usually the risk. The bigger question is whether the person doing it checks the geyser properly first, rather than just strapping on a blanket and leaving. A rushed check misses a failing anode or a valve that needed attention.

Can you get the paperwork your insurer needs after a geyser claim?

Ask for photos and a short written record of any work done on your geyser, since that's what most insurers want to see. Keep that paperwork even for small jobs like a blanket or timer, because it builds a record of the geyser's condition over time.

Will someone actually answer when you reach out?

That's worth testing before you commit to anyone, small job or big one. Send a message and see how long it takes to hear back and whether the reply actually answers your question or just books a slot.

Will you hear back, even over a weekend?

Response times often slip over a weekend, so it's a fair thing to ask about upfront rather than assume. A geyser problem doesn't wait for Monday, so know before you need it whether a plumber answers outside office hours.

Will the plumber arrive with the right tools to sort it on the one visit?

For a blanket and timer, the job is simple enough that one visit should cover it, as long as the geyser itself is in decent shape underneath. Where a second visit becomes likely is if the check turns up a separate issue, like a failing anode or old wiring that needs sorting first.

About the author

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