Why does my shower go cold after a few minutes?

1. Someone else is using hot water

If another tap, appliance, or shower in your home is using hot water at the same time, it can reduce the flow to your shower.

Solution: Ask others to avoid using hot water while you're showering, or shower at different times.

2. Your boiler is too small

If your combi boiler doesn't have enough capacity, it may struggle to heat water fast enough when demand is high.

Solution: You may need a larger boiler, or reduce hot water usage elsewhere while showering.

3. The shower mixer is faulty

Electric showers have a heating element that can fail. Mixer showers rely on a steady supply of hot water.

Solution: For electric showers, the heating element may need replacing. For mixer showers, check that hot water flows properly from other taps.

4. Low water pressure

If your hot water pressure is lower than your cold water pressure, the cold can overpower the hot water in a mixer shower.

Solution: Check your water pressure. You may need a pump or pressure-balancing valve.

5. The boiler is cutting out

Some boilers have a safety feature that cuts out if they overheat or detect a problem.

Solution: Check your boiler's error codes or warning lights. You may need a boiler service or repair.

6. A faulty thermostatic valve

Thermostatic mixer showers have a valve that maintains temperature. If it's faulty, it may not work properly.

Solution: The valve may need cleaning (limescale can cause issues) or replacing.

Quick checks

Before calling a plumber, try:

1. Running only the shower (no other hot water)
2. Checking if other hot taps work properly
3. Looking at your boiler for error lights
4. Testing the shower at different times of day

Summary

• Multiple hot water uses can reduce shower temperature
• A small or faulty boiler may not heat water fast enough
• Low pressure or faulty valves can cause temperature issues
• Check other taps and your boiler before calling a plumber
• If problems persist, consult a qualified plumber