Why is my shower not getting hot?
A shower that stays cold or only reaches lukewarm may have a problem with the hot-water supply, shower controls, a thermostatic cartridge or—if it is an electric shower—the unit's power or internal parts. Comparing it with other taps can quickly narrow down where the fault lies.
Do other taps have hot water?
First, check a hot tap at the basin or kitchen. If every outlet is cold, the problem is probably with the boiler, hot-water cylinder or wider supply rather than the shower itself. Check the heating controls and any clear fault message, but do not remove boiler covers.
If other taps become properly hot but the shower does not, the fault is more likely to be within the shower valve, controls or local pipework.
Why can a mixer shower stay cold?
A mixer shower blends separate hot and cold supplies. A stuck or worn thermostatic cartridge can prevent the temperature from increasing. Limescale, debris, a partly closed service valve or a restricted hot supply can have a similar effect.
Some controls have a safety stop around the normal showering temperature. Pressing its release should allow the control to turn further, but never force a stiff handle.
What if it is an electric shower?
An electric shower heats cold mains water inside the unit, so hot taps elsewhere may still work normally. Check whether the shower has power and whether its indicator lights show a fault. A very high flow setting can also make the water feel cooler because it has less time to heat.
Do not open the casing or attempt an electrical repair. A shower that trips the electrics, smells hot, makes unusual noises or shows scorching should be switched off at its isolator and checked by a suitably qualified professional.
Could water pressure be the cause?
Some showers need balanced or adequate supplies to mix correctly. If the temperature changed after plumbing work, or alters sharply when another tap or appliance runs, pressure or flow may be part of the problem. A fitter can check the supplies and whether the shower type suits the home's plumbing system.
When should I arrange a repair?
Arrange an inspection if the controls are stiff, the shower remains cold while other taps are hot, or the problem keeps returning. A plumber can test mixer valves and water supplies; an electric-shower fault may need a qualified electrician or the manufacturer's approved engineer.
Stop using the shower immediately if there is leaking near electrical parts, a burning smell, scorching or repeated tripping.
Quick cold-shower checklist
- Compare the shower with hot taps elsewhere.
- Check heating controls for a clear fault message.
- Make sure the shower's temperature control is not at its safety stop.
- For an electric shower, check the power indicator without opening the unit.
- Notice whether using another outlet changes the temperature.
- Never force controls or remove electrical covers.