Heating · London & Herts
Immersion heaters in London
The short answer
An immersion heater is an electric element inside a hot water cylinder that heats water like a kettle. If it stops heating, the usual causes are a tripped switch, a failed thermostat or a burnt-out element. Elements and thermostats can be replaced, and the cylinder usually doesn't need changing.
Immersion heaters provide hot water on their own or as a back-up to a boiler. We repair, maintain and install them, and diagnose why they've stopped working, from electrical faults to limescale build-up.
In hard-water areas like London and Hertfordshire, limescale coats the element and shortens its life. We can advise on settings and maintenance to keep it running efficiently.
How it works
Immersion heaters: what happens when you call
- 01
Call or message us
Tell us about the immersion heater. Phone, WhatsApp or book online, 24 hours a day. We'll ask a few quick questions and tell you when we can be there.
- 02
Diagnosis and quote
The engineer finds the cause of the immersion heater fault, explains it in plain English and gives you a clear quote before any work starts.
- 03
Repair and clean-up
We repair or replace the element or thermostat, test everything, tidy up and talk you through how to avoid it happening again.
FAQs
Immersion heaters questions, answered
Why is my immersion heater not heating water?
Check the switch is on and the circuit breaker hasn't tripped. If power is reaching it, the element or thermostat has probably failed. A failed element is common in hard-water areas, where limescale builds up and makes it overheat. Both parts can be replaced without replacing the cylinder.
How long does an immersion heater element last?
Lifespan varies a lot with water hardness and use. In London and Hertfordshire, where water is hard, limescale on the element is the main reason they fail early. Setting the thermostat sensibly rather than at its maximum helps. Signs it's failing include slow heating and crackling noises.
What temperature should my immersion heater be set to?
Stored hot water should be kept at 60°C to control Legionella bacteria. Setting it much higher wastes energy and increases limescale and scalding risk. If your water is coming out far hotter or colder than the setting, the thermostat may be faulty.
What customers say
All 165 reviewsEljo from Urgent Plumbers London Ltd is one of, if not the most responsive tradesman I've come across - replied to queries and messages quickly without fuss, and clearly explained issues/reasoning with any work required. Always arrived when he said he would too and was happy to provide all relevant documentation (Gas Safe etc) when asked - would recommend. Quoted for boiler service/replaced our boiler when it was found to be un-serviceable.
Urgent Plumbers were fantastic when my boiler leaked. It was at the worst time possible -early on a Sunday morning when I was rushing out to work. He was so calm , turned up quickly as promised and then was so efficient at working out and fixing the problem. He was also so kind as I was terrified how much it would all cost for a Sunday emergency call out Thank you so much - you're an absolute hero
I'm really pleased with the service. All in the same day the gentleman came to fix an issue in the bathroom. A leaking pipe fixed. Very friendly and professional. I totally recommend their service. Thanks again 😊
Immersion heaters near you
Immersion heaters? We can help today.
Call any time, day or night. We'll tell you when we can be there and give you a clear price before we start.