Installing or replacing a water heater: cost and what to know

The short answer: if you are swapping a dead instant water heater for a similar new one and the existing wiring is still sound, the labour is usually RM 100–300 on top of the unit itself (about RM 200–900 in the shops, depending on whether it has a built-in pump). A storage heater, or a bathroom that never had a heater point before, is a bigger job — not because of the plumbing, but because of the dedicated wiring it needs, which pushes the electrical portion to RM 300–600. That wiring is always carried out with our licensed partner contractor, Suruhanjaya Tenaga compliant.

Below is where the money actually goes — and the two things that matter far more than which brand you pick.

Instant vs storage: which one are you actually buying?

	Instant heater	Storage heater
Unit price	RM 200–900	RM 500–1,500+
How it works	Heats water as it flows, one shower at a time	Keeps a tank of hot water, stronger steady flow
Wiring	Existing heater point usually reusable	Needs its own dedicated circuit
Best for	Most terrace-house bathrooms	Rain showers, families queuing for the bathroom

One thing we always mention before anyone buys: a big ceiling rain shower fed by a basic instant heater is a common disappointment. Instant units can only heat so much water per minute, so a rain shower turns into a lukewarm drizzle. If your renovation plan includes a rain shower, budget for either a pump-assisted instant unit or a storage heater from the start — changing your mind later means new wiring.

The two things that matter more than the brand

The ELCB and the earthing. A water heater is the one appliance in your house that combines mains electricity, water and your bare skin, and the ELCB (earth-leakage breaker) plus a proper earth connection are what stand between a worn heating element and a shock in the shower.

In older houses around Seri Kembangan, Serdang and Kajang we regularly open up a heater point and find one of two things: the heater was tapped off the nearest plug circuit years ago with no earth-leakage protection at all, or the earth wire is physically there but was never actually connected behind the casing. The new heater's built-in safety cut-out is a last line of defence, not a substitute for either. Whoever installs yours should test the ELCB with its test button and verify the earth — if the installer doesn't mention earthing at all, that tells you something.

What's plumbing and what's wiring

Plumbing portion (RM 100–500): mounting the unit, connecting the inlet and shower, sealing the pipe joints, and for storage heaters a drain line for the pressure-relief valve — a small pipe that must drip somewhere safe, not into your ceiling.
Wiring portion (RM 80–600): the dedicated circuit, double-pole isolator switch, ELCB check and earthing. This part is never a DIY job and never a “my cousin can do it” job — ours is done by our licensed partner contractor.

Honest cost picture

Job	Typical labour
Like-for-like instant swap, wiring reused	RM 100–300
Swap plus wiring or earthing repairs	add RM 150–600
Brand-new instant heater point	RM 400–900
Storage heater with dedicated circuit	RM 500–1,100

Add the unit price on top — buy the unit yourself at any hardware or online sale if you like; we install what you supply.

Repair or replace?

An instant heater that is ten years old and has started tripping the breaker or running rust-tinted water is at the end of its life — the heating element's protective coating wears out, and replacing elements on cheap units costs nearly as much as a new heater. Under ten years with a specific fault, a repair can still make sense. If you are pricing a larger bathroom job anyway, see our price guide or the full list of services — a heater swap folds neatly into a bathroom refresh.