Why is my hot water not working?
No hot water is one of the most common calls we get, and the cause is often something you can check yourself. Work through these checks first. If none of them sorts it, we can send an engineer.
- 1 to 1.5bar: check the pressure first
- 60°Ccylinder setting, if you have a tank
- £120repair visit, parts priced first
Five checks first
Before you book an engineer, a few checks take about ten minutes and often get the hot water back.
They work for most boilers, whether you have a combi or a hot water cylinder.
1. Look for a fault code
The display often tells you the cause.
Most modern boilers show a code when something stops them working. Common ones:
- Worcester Bosch EA: the boiler can't detect a flame
- Vaillant F28: it failed to light. F22 is low water pressure
- Ideal L2: it failed to light
- Baxi E133: gas supply or ignition
Not on the list? Our fault code page covers more.
The display
2. Check the pressure and the gas
The two most common causes.
The pressure
The gauge should read 1.0 to 1.5 bar with the heating cold. Below 1 bar, top it up with the filling loop. Our pressure guide shows how.
The gas
- Does the gas hob light?
- On a prepayment meter, is there credit?
- Is the lever on the gas meter in the on position, if it's safe to reach?
Smell gas? Open the windows, don't touch electrical switches, turn the gas off at the meter if it's safe to reach and call 0800 111 999.
Checking the gas
3. Check the controls, then try a reset
Sometimes the boiler is fine and hasn't been asked to come on.
- Is hot water switched on at the programmer or in the app?
- Has a power cut or the clocks changing reset an older timer?
- With a hot water cylinder, is its thermostat set to about 60°C?
- With Hive or another smart thermostat, is the app in holiday mode?
A reset
Press the reset button as the boiler's manual says, once. If it fires up, that may be all it needed. If it locks out again straight away, don't keep resetting it. Call an engineer.
Controls and reset
4. In freezing weather, the pipe outside
The most common winter fault we see.
Condensing boilers drain water through a white plastic pipe, often to outside. In a hard frost it can freeze and the boiler shuts down, sometimes with a gurgling sound first.
Pour warm water, not boiling, along the pipe outside until it thaws, then reset the boiler. Our frozen condensate pipe guide has the full steps.
Still no hot water?
Then it's likely a faulty part, such as the diverter valve, a sensor or the circuit board. These need a Gas Safe registered engineer. A repair visit is £120 inc VAT, and any parts are priced before we fit them.
When it's a part
Which one sounds like you?
- A code on the displayLook it up
What the code means.
- Pressure below 1 barTop it up
Step by step.
- Heating works, hot water doesn'tBook a repair
Often the diverter valve on a combi.
- Hot water but no heatingThe other way round
Our guide to that one.
Common questions
Why do I have heating but no hot water?
On a combi, the usual cause is the diverter valve, which switches the boiler between heating and hot water. With a cylinder, check the hot water is switched on and the cylinder thermostat is set to about 60°C.
Can low pressure stop the hot water?
Yes. Below about 1 bar many boilers lock out and show a fault. Topping up often gets it going again.
Is it safe to reset my boiler?
Yes, once, as the manual describes. If it locks out again straight away, stop and call an engineer.
How do I thaw a frozen condensate pipe?
Pour warm water, not boiling, along the pipe outside until it thaws, then reset the boiler.
Do you work on all boiler makes?
Yes. Our Gas Safe registered engineers repair all major makes, including Worcester Bosch, Vaillant, Ideal and Baxi.
How much does a repair visit cost?
£120 inc VAT. If we can fix it on the visit, that's all you pay. Any parts are priced before we fit them.
Related pages
Not sure what you need? Give us a shout.
Book online in a couple of minutes or give the office a call, Mon to Fri, 9am to 5pm. We'll tell you what we think, and if the answer is to leave things as they are, we'll say that too.
Worcester Bosch Accredited Installer
Guarantees of up to 12 years on the boilers we fit. Gas Safe registered. Fife Trusted Trader. 400+ customer reviews.