Battery vs Electric Gas Geysers — What's the Difference?
Battery units — the Dewhot and Cadac — light with torch-style batteries and need no electricity at all, which makes them cheaper and completely load-shedding proof. Electric units — the Paloma and Rinnai — plug in, hold a constant preset temperature and handle mixer taps far better. Both burn the same gas; the difference is how they light and how well they control.
How do battery-ignition geysers work?
A pair of torch batteries in a housing on the unit provides the spark that lights the burner when it senses water flowing. That is the batteries' only job — they do not heat anything and they do not run the unit.
- No plug point needed. Which means no electrician, no cable run and no dependence on Eskom. It also means a simpler, cheaper installation.
- Batteries need replacing. Typically about once a year depending on use. Lazy ignition is the warning sign.
- They must be covered outdoors. This is not optional on the Garden Route. Rain and coastal moisture corrode the board and the wiring loom, and a corroded loom is the single most common reason we condemn an otherwise young battery unit.
- Temperature control is good, not perfect. The Dewhot 16L Constant Temperature holds a set temperature well for a normal household; the Cadac 16L Ecoflow is simpler and built to light on weak flow.
How do electric (mains) geysers work?
They run off a weatherproof plug point near the unit. The electricity powers electronic control rather than heating — that control is what gives you a stable, preset temperature no matter how the flow changes.
That stability is what people are really buying. Set the Paloma 20L or Rinnai 20L to your shower temperature and it holds it while you adjust the tap, while somebody opens the kitchen tap, and while the inlet water gets colder in July. There are no batteries to replace, and neither unit generally needs a weather cover.
They also modulate properly, which is why they are the right units where the house is on mixer taps, where there is more than one bathroom, and where the geyser has to run inline after a solar tank. Battery units cannot do inline work at all — preheated water confuses them.
The only thing they need from you is power, and if you have an inverter for the house, adding the geyser plug point to the backed-up circuit is a small job.
Which is right for my home?
Work up the ladder from what the house actually demands. Buying the wrong end of it is how people end up disappointed with gas.
- Flats, granny flats and low pressure — Cadac 16L Ecoflow, from around R12,200 installed. Low-flow start, battery, practical. More detail on flats and granny flats.
- Standard family homes, mid budget — Dewhot 16L Constant Temperature, from around R15,000 supplied and installed. Battery, covered, reliable.
- Whole house, premium — Rinnai 20L from around R21,500 installed, or Paloma 20L from around R22,000. Mains powered, constant temperature, mixer-friendly, solar-inline capable.
Install prices move with your plumbing layout, gas line distance and extras like a cylinder, cage or weather box, so treat those as starting points and get it quoted. The buying guide lays the five models out side by side.
What about weather exposure on the Garden Route?
Coastal moisture is not a theoretical problem here. Salt-laden air and wind-driven rain get into anything unprotected, and electronics on the outside of a house take the worst of it.
Battery units must be under a proper weather cover or box — that is the difference between a Dewhot that runs for years and one that fails with a corroded loom. It matters most in Pacaltsdorp, Herolds Bay, Glentana and anywhere with a sea-facing wall, but wind-driven rain reaches units in Blanco and Heather Park too.
The Paloma and Rinnai are built for outdoor mounting and generally do not need a cover, although estate or body corporate rules may still require the unit to be screened. If your installation has been out in the weather unprotected for a while, a gas safety inspection will pick up corrosion before it becomes a breakdown.
Battery vs Electric — Common Questions
Around a year is the usual pattern, though it depends entirely on how often the unit lights. A busy family home works the igniter far harder than a holiday cottage used three weekends a year. You will hear it before it fails completely: the click becomes lazy, the unit takes two or three attempts to catch, and the flame is slower to establish. Replace them then rather than waiting for the cold shower, and keep a spare set in the house.
Not sure which ignition suits your house?
Tell us how many bathrooms you run, whether you have backup power and how exposed the wall is. You will get a recommendation with the reasoning behind it, and a quote for the install.