How to Connect a Geyser in South Africa (Wiring & Plumbing Guide)
24 May 2026 · Plumbers On Duty
Quick answer
A standard 150L electric geyser needs 6 connections: cold-water inlet, hot-water outlet, temperature-and-pressure (T&P) safety valve, vacuum breakers on both hot and cold lines, expansion relief drip tray and 4mm² wiring to your DB board on a dedicated 20A breaker.
In South Africa, a geyser install must be signed off with a PIRB Certificate of Compliance for insurance to cover it. DIY installs that leak or burst are not covered. Find a PIRB plumber near you.
What you'll need
- Geyser (150L is standard for a 3-bedroom home)
- T&P safety valve (400kPa for low-pressure, 600kPa for high)
- Two vacuum breakers (one hot, one cold)
- Expansion relief / drip tray with overflow to outside
- 22mm copper or PEX-AL pipe + fittings
- 4mm² twin-and-earth cable
- 20A double-pole isolator near the geyser
- Geyser blanket and pipe lagging
Connection sequence (overview)
- Mount the geyser horizontally in the roof (or vertically in a cupboard for some models) on supports rated for the full water weight — a 150L geyser weighs about 170kg when full
- Drip tray underneath with an overflow pipe through the eaves to outside (mandatory under SANS 10254)
- Cold-water inlet: install a vacuum breaker minimum 300mm above the geyser top, then run cold to the inlet
- Hot-water outlet: vacuum breaker minimum 300mm above the geyser, then run hot to the manifold
- T&P safety valve: screw into the dedicated boss, plumb its discharge to the drip tray (NOT outside directly — it must visibly discharge into the tray so failures are obvious)
- Expansion relief: separate discharge pipe to outside under the eaves
- Electrical: isolator switch within 1m of the geyser, 4mm² cable back to a dedicated 20A breaker on the DB, earth-bonded to the body
- Bond the cold and hot pipes to earth as required by SANS 10142
Why this needs a PIRB plumber
- Insurance won't pay out on a self-installed geyser failure
- An unbalanced pressure valve can rupture the cylinder
- Inadequate drip-tray drainage means a small leak destroys your ceiling
- The COC is required by Cape Town and requested by conveyancers nationally
Cost of a professional install
- 150L geyser supply + install + COC: R7,500–R14,000
- 200L geyser: R9,500–R17,000
- Solar geyser system: R20,000–R45,000
- Heat pump: R28,000–R55,000