Domakihub How to Replace an Electric Shower Unit Safely
A clear, step-by-step guide for homeowners, rental managers, and hotel teams in Greece.
Reviewed by Domakihub home & decor pros · 2026-06-23 · 5 min read
An electric shower that loses pressure, trips the breaker, or simply stops heating is one of the most disruptive faults in any home, holiday rental, or hotel room. The video above from Plumbing Tips walks through an actual job-site replacement so you can see the process in real time; this guide adds the preparation, safety requirements, and decision points you need before anyone picks up a screwdriver. Because an electric shower is wired directly to the mains supply, the electrical disconnection and reconnection work must be carried out by a licensed electrician in Greece — understanding each stage helps you brief the right trades, keep costs down, and get hot water back fast.
Why Electric Showers Fail — and When Replacement Beats Repair
Electric showers heat water on demand using a resistive element, typically rated between 7.5 kW and 10.5 kW. Over time, limescale build-up (a particular issue in the hard-water areas of Attica and the Aegean islands) coats the element and reduces efficiency until the unit either overheats or cuts out on its thermal trip. Solenoid valves, flow switches, and pressure sensors also wear out after several years of daily use. When a repair quote exceeds roughly half the cost of a new unit, replacement is almost always the better investment.
Replacing like-for-like — same kilowatt rating, same inlet and cable entry points — is the simplest scenario and keeps the job to a single day. Upgrading to a higher-rated unit (say, from 8.5 kW to 10.5 kW) may require a heavier cable and a larger MCB in the consumer unit, which means more electrical work and a correspondingly higher quote from your electrician.
Who Does Which Part of the Job in Greece
In Greece, electrical installation and alteration work on fixed wiring — including connecting or disconnecting a shower from its dedicated circuit — must be performed by a licensed electrical contractor (αδειούχος ηλεκτρολόγος). Attempting this yourself without a licence is both illegal and genuinely dangerous: the shower circuit carries enough current to cause a fatal shock and must be protected by an RCD (residual-current device) at the consumer unit. Your electrician will isolate the circuit, confirm it is dead with a voltage tester, and handle all connections at both the unit and the consumer unit.
The plumbing side — disconnecting and reconnecting the cold-water supply inlet — is straightforward and can be handled by a plumber or, in many Greek properties, the same electrician if they are comfortable with basic push-fit or compression fittings. If you are a hands-on owner and there is an accessible isolating valve on the water supply to the shower, you can legally close that valve and cap the pipe yourself; however, reconnecting to the new unit is still best left to a professional to avoid leaks inside the wall.
Replacing an Electric Shower: The Five Stages
- 1
Isolate both supplies and confirm they are dead
Your electrician switches off the dedicated MCB (or RCBO) in the consumer unit and locks it off or tapes it. They then use a voltage tester to confirm there is no live voltage at the shower's terminal block — never skip this step. Simultaneously, close the isolating valve on the cold-water feed (usually under the shower or inside an adjacent cupboard) and open the shower briefly to release residual pressure. Only once both supplies are confirmed dead should the cover of the old unit be removed.
- 2
Disconnect and remove the old unit
With the cover off, your electrician photographs or notes the existing cable connections (live, neutral, earth) before removing them from the terminal block. The water inlet pipe is then disconnected — expect a small amount of residual water to drain out, so have a towel ready. Most electric shower units are fixed to the wall with two or four screws through a back plate; once these are removed the old unit lifts away. Inspect the wall behind it: if tiles are cracked or the surface is damp, address this before fitting the new unit.
- 3
Prepare the wall and route cables and pipework
Hold the new unit's back plate against the wall and compare cable and pipe entry positions with the old unit. Manufacturers design many current models with multiple entry knockouts so that existing routes align without re-chasing the wall. If you are upgrading to a higher-rated unit, your electrician will now run the new, heavier cable from the consumer unit — this is the most time-consuming part of an upgrade job. Fit the back plate securely to the wall using appropriate fixings for the substrate (rawlplugs in masonry, cavity fixings in plasterboard).
- 4
Connect water and electrical supplies
The plumber (or electrician) connects the cold-water inlet using the fitting supplied with the new unit — typically a 15 mm compression or push-fit connector. Slowly open the isolating valve and check for leaks before closing the unit cover; a drip inside the casing can damage the element immediately. Your electrician then connects live, neutral, and earth conductors to the new terminal block, following the manufacturer's wiring diagram. They also verify that the circuit is protected by an RCD of the correct rating at the consumer unit, as required by current electrical regulations.
- 5
Test, commission, and document
With the cover secured, your electrician restores power at the consumer unit. Run the shower on its lowest power setting first and check for leaks at the water inlet. Then test each power and temperature setting in sequence. The RCD should be tested by pressing the test button on the consumer unit — it should trip and cut power immediately. Note the installation date, unit model, kW rating, and the name of your electrician in a property maintenance log; this is especially important for holiday rentals and hotels where annual safety checks may be required by insurers or local licensing authorities.
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FAQ
- Can I replace an electric shower myself in Greece to save money?
- You can legally remove the old unit and mount the new back plate yourself, but you must not touch the electrical connections — disconnecting or reconnecting a mains circuit without a licence is illegal in Greece and extremely dangerous. Hiring a licensed electrician for just the electrical work, while you handle the physical swap, is a sensible way to reduce labour costs without breaking the law.
- Does the new shower have to be the same kilowatt rating as the old one?
- Not necessarily, but upgrading to a higher kW rating usually requires a larger cable and a bigger circuit breaker, which adds cost and work. Replacing like-for-like (same kW) is the cheapest and fastest option. If you want to upgrade, ask your electrician to assess the existing cable size before you buy the new unit — a 10.5 kW shower on an undersized cable is a fire risk.
- How long does a replacement take and what should it cost in Greece?
- A straight like-for-like swap on an accessible unit typically takes two to four hours including testing. Expect to pay roughly €80–€150 for the electrician's time in most Greek cities, on top of the unit cost (budget €100–€250 for a decent 8.5–10.5 kW model). Jobs that require re-running cable or chasing walls will cost more. Always get a written quote and check the electrician holds a valid licence (άδεια ηλεκτρολόγου).