Electric Shower Stopped Working

What exactly has stopped?

The symptom narrows the fault down before anyone opens the box, so note which of these you have.

• No lights on the unit and no water: power is not reaching the shower. Start at the switch and the consumer unit.
• Lights on, you hear a click, but no water comes out: the unit has power but its inlet solenoid valve is not opening, or there is no cold water getting to it.
• Water flows but stays cold: the heating element, the thermal cut-out or the pressure switch that tells the element to come on.
• It works for a minute then goes cold or cuts out: overheating, usually from scale or low flow, tripping the thermal cut-out.
• Water pouring from the bottom of the unit: the pressure relief device has done its job, almost always because the head or hose is blocked.
• The breaker trips as soon as you switch on: an earth fault or a burnt connection. Leave it off.

If you smell burning or see brown or melted plastic around the switch or the unit, switch the shower circuit off at the consumer unit and do not use it again until an electrician has looked at it. Loose connections on a shower circuit carry a high current and are a genuine fire risk.

What can I safely check myself?

These are all outside the unit. None needs the cover off.

Check the ceiling pull-cord or wall switch is on. Most have a small neon or red light that shows when the circuit is live. Then go to the consumer unit. An electric shower has its own breaker, usually marked as the shower and rated around 40 to 50 amps. If it has dropped, or an RCD has tripped, push it back up once. If it trips again straight away, stop. A breaker that keeps tripping is protecting you from a real fault, and resetting it again and again lets a burnt connection get worse.

Next, the water. An electric shower runs from the cold mains, so turn on the kitchen cold tap. If that is weak or dead too, the problem is the supply, and our pages on no water in the house and low shower pressure will get you further. Check the small service valve on the pipe into the shower, often under the unit or behind a panel; the slot should run along the pipe.

Finally, take the head off the hose and try the shower without it, aiming the hose into the bath. A head packed with scale stops water leaving fast enough, the unit senses the pressure and either shuts down or bursts its relief device. Descale the head in vinegar or a kettle descaler before refitting.

What fails inside an electric shower?

Once power and water are both confirmed, the fault is in the shower itself. These are the usual suspects and what they point to.

The pressure relief device is a small plastic part designed to split or blow if pressure inside the unit gets too high, which happens when the head or hose is blocked. It is a safety part, not a defect, and brands such as Triton and Mira sell replacements that typically cost £5 to £25. Fitting a new one without clearing the blockage means it will go again within days.

The solenoid valve opens to let water in when you press start. It fails with scale or a burnt-out coil, giving you lights and a click but no flow. The thermal cut-out protects the element from overheating. On some models it resets itself, on others it has a button inside the unit, and on some it is a one-shot part that must be replaced. A heating element that has burnt out gives flow but no heat on any setting.

On most units these parts are replaceable, but the job means isolating at the consumer unit, taking the cover off and working next to terminals that carry mains current. It is a job for a competent person, not a first-time DIY repair.

Never take the cover off an electric shower with the circuit live. Switching off at the pull-cord is not enough when you are working on it: turn off its breaker at the consumer unit as well.

Repair or replace?

Electric showers are cheap enough that age matters. A unit that has a single failed part and is only a few years old is worth repairing. One that is well over ten years old, has had scale problems for a while, or has scorch marks on its terminal block is usually better replaced. Parts for older discontinued models can also be hard to find.

A typical like-for-like replacement unit costs roughly £100 to £350 for the shower itself, depending on the power rating and features. The simplest swap uses the same kW rating, the same cable entry and the same water inlet position, so the new unit covers the old holes. Going up in power, say from 8.5 kW to 10.5 kW, is not a straight swap: the cable, the breaker and the switch all have to be rated for the higher load, and that is an electrician’s call. In England a new or upgraded shower circuit is notifiable work under Part P of the Building Regulations, so it should be done by a registered electrician who can self-certify it.

Plumbers handle the water side of an electric shower: the supply, the service valve, flow problems and leaks. The circuit belongs to an electrician. If you are not sure which you need, describe the symptom above when you call, because it usually tells you.

When it becomes urgent

A shower that is simply dead is an inconvenience, and deciding whether a broken shower can wait is quick once you know the symptom. It becomes urgent when water is leaking from the unit or its pipe and reaching the ceiling below, when the breaker will not stay on and other circuits are affected, or when you can smell burning. For a leak, turn off the service valve to the shower or, if you cannot find it, the stopcock, and see what to do in the first ten minutes of a water leak.

If the shower is the only way to wash in the house, especially with children or someone unwell, that is a fair reason to get it looked at the same day. For water-side faults, our no hot water repair visits cover showers as well as boilers and cylinders. The £60 call-out applies at any hour, and the repair price is agreed with you on site before any work starts; see pricing for how that works.