Guides · Heat Pumps
Heat pumps come up less often in conversation than solar geysers, but they're worth understanding, they're genuinely one of the most efficient ways to heat water, and they work in situations a solar geyser can't, particularly where roof space or orientation is limited.
How a heat pump actually heats water
A heat pump doesn't generate heat directly the way an electric element does. It extracts heat from the surrounding air, the same principle as a refrigerator working in reverse, and uses that to heat the water in a connected cylinder. Because it's moving heat rather than generating it from electricity directly, it uses a fraction of the power a standard electric geyser element does for the same amount of hot water.
Heat pump vs solar geyser
- Roof space and orientation. A solar geyser needs decent north-facing roof exposure. A heat pump's outdoor unit just needs ground or wall space with reasonable airflow, so it works on properties where the roof doesn't suit solar.
- Consistency. A heat pump performs fairly consistently day to day, since it's drawing on ambient air temperature rather than direct sun. A solar geyser is more efficient on a sunny day but relies more on its backup element in overcast weather.
- Where they're installed. The outdoor unit sits at ground level or on a wall next to the house, connected to an indoor or nearby cylinder, rather than living on the roof.
What installation involves
The outdoor unit is mounted on a level base with clearance for airflow, connected to a hot water cylinder via insulated pipework, with a dedicated electrical isolator installed alongside it. Where we're replacing an existing electric geyser, we assess whether the existing cylinder can be reused or whether a heat-pump-compatible cylinder is needed. As with any water heating installation, everything is signed off to current compliance regulation.
Heat pumps across the Southern Suburbs
We install and service heat pump water heaters throughout the Southern Suburbs, including properties in Bishopscourt, Newlands and Rondebosch where mature trees often limit roof sun exposure, which is exactly the kind of site where a heat pump is worth considering over solar. The same applies down the South Peninsula, in Muizenberg, Noordhoek, Kommetjie, Simon's Town and Scarborough, all on one flat call-out rate.
Common questions
Does a heat pump work at night or in winter?
Yes. Unlike solar, a heat pump doesn't rely on direct sunlight, it draws heat from the surrounding air, so it continues working overnight and through Cape Town's winter, though efficiency does drop somewhat in very cold conditions.
Is a heat pump noisy?
There's a fan, similar in character to an outdoor air conditioning unit, so placement matters, we'll advise on the best position to keep it well clear of bedroom windows.
Can a heat pump replace my existing geyser?
In most cases, yes, either by connecting to your existing cylinder if it's compatible, or as part of a full replacement. We assess this on site rather than guessing from a phone call.
Heat pumps and the Cape Town winter
A heat pump draws heat from the outside air, so it works least efficiently on the coldest days. Cape Town's coastal suburbs seldom get close to freezing, which suits heat pumps well. They keep working efficiently through a typical Cape winter, just when a solar geyser leans hardest on its backup element.
Prefer to use the sun? Read what a solar geyser installation involves.