What next, no butter on your toast? The world isn’t fair. Plus, sometimes you won’t get hot water from your boiler. Even if you have heating.
Boilers can be ‘half broken’ as it turns out.
It’s perfectly possible to have your heating pumping away whilst hot water eludes you.
Key Points:
Check the Thermostat: Ensure the thermostat is set correctly and is functioning properly.
Inspect the Boiler Pressure: Low pressure can prevent the boiler from heating water; check and top up if necessary.
Pilot Light or Ignition Issues: If the pilot light is out or the boiler isn’t igniting, this could be the cause of no hot water.
Diverter Valve Problems: The diverter valve might be stuck, preventing hot water from reaching the taps.
Frozen Pipes: In cold weather, frozen pipes can block water flow, leading to a lack of hot water.
Error Codes: Check if the boiler is displaying any error codes and refer to the manual for troubleshooting.
Call a Professional: If basic troubleshooting doesn’t resolve the issue, it’s advisable to contact a Gas Safe registered engineer.
No hot water from combi boiler
If your combi boiler is not firing up for hot water, these are some of the most common causes, especially if you find that your heating is still working, but you have no hot water.
Common reasons why there is no hot water from your boiler:
#1 - Pilot light not lit (no flame = no hot water)
Boilers burn gas (or oil) – and to do so requires a pilot light.
This is only really relevant if you have a super old boiler that quite honestly, more than likely needs replacing.
Pilot lights are tiny Olympic flames which carry the whole weight of a family’s comfort and well-being.
In some ungodly circumstances, this flame could go out or more commonly, just fail to catch. This will lead to total failure, meaning you'll get no hot water from your boiler. This essentially turns your boiler into the world’s ugliest piece of interior decoration, since it has stopped delivering hot water.
In older boilers, you might actually be able to see the pilot light through the framework of your boiler, but in more modern boilers, you’ll be alerted of its failings through an error code on a depressing black & white monitor.
There’s no need to summon a fire-inducing demon. Simply check your boiler’s manual to see how to reignite your boiler’s pilot light. To reignite passion in your marriage, we’ve found the boiler manual completely useless.
If that doesn’t work – you will require a heating engineer to tend to your broken boiler – hopefully, you won't need a new boiler (if you do, learn more about the best combi boilers and check out our best boiler brands article).
Luckily, in most cases, that'll be a DIY fix and a quick (free) way to get your boiler's hot water back.
Cost to fix (and get your hot water back):
DIY: £0.00
Engineer: £75-£160
#2 - Frozen pipes
Barring a global nuclear disaster, this will only apply to winter conditions. And maybe the nuclear disaster heats up your water as a side effect, so you’d have nothing to worry about.
A condensate pipe leads from our boiler to an outside wall (or sometimes an internal drain) and allows for the expulsion of condensation water.
Due to the slow drip of water and the predictable nature of physics, this will occasionally freeze over.
Upon detecting this, your boiler will shut down for safety reasons, giving you no hot water (or heating) at all. It’s essentially the same as your boiler going on strike because of its working conditions.
Fortunately, this is easily fixed at home by slowly melting the frozen area by wrapping the pipe in cloth or pouring some warm water over the condensate. Since your hot water will be out, most people use the cloth.
You’ll need to reboot your boiler after addressing this.
Once done, your boiler should have its hot water back.
Cost to fix (and get your hot water back):
DIY: £0.00
Engineer: £50-£150
#3 - Faulty Diverter valve
Inside every boiler lies a diverter valve.
It's a miniature traffic director dictating the flow of water like an outcasted member of the X-Men.
A failure of this device, potentially caused by natural system corrosion or metallic built-up over time might only allow for hot water to be delivered to your radiators and starve the hot water supply – hence, no hot water from your boiler. Your greedy radiators are taking all the hot water and preventing you from showering.
Outside of a potential error code alter, it isn’t something you’ll be able to diagnose at home and a heating engineer is most definitely required.
The best case scenario here is a diverter valve replacement that might set you back around £200 with labour costs but take into account the age and condition of your boiler before throwing repair money at it.
If your boiler is broken beyond repair, we fit new Viessmann boilers with 10-year parts and labour warranties from £1,695 (all over the UK).
Cost to fix (and get your hot water back):
DIY: Impossible (unless you happen to be a Gas Safe technician)
Engineer: £180-£250
#4 - Pressure issues: Over or under pressurisation
With the likely culprit being the aforementioned leakage, under or over-pressurisation could result in no hot water from your combi boiler. Like Goldilocks complaining after breaking and entering, your prissy boiler needs just the right pressure.
If your boiler is low on pressure, it can usually be solved simply through a DIY top-up.
An over-pressurised boiler can also be combatted at home through some simple radiator bleeding. It’s the heating equivalent of having your toddler run laps to tire them out.
If that wasn’t to solve the issue, it’s a broken boiler part requiring a heating engineer or a new boiler that’s the source of your lack of hot water.
You may also want to consider a power flush to improve the quality of your heating water and prevent blockages.
Cost to fix (and get your hot water back):
DIY: £0.00
Engineer: £50-300
You may be interested in Gas Engineer Allen Hart explaining the most common boiler problems and how you can resolve them in the video below:
No hot water from regular/system boiler
Receiving heating but no hot water from your boiler is more likely with a conventional or system boiler that has a hot water cylinder.
#1 - Thermostat/timer fault
If you’re savvy with your tech or keep a watchful eye on your energy usage, you’ll likely be using your boiler timer to control when it’s in operation.
A thermostat issue would only cause an issue with heating, rather than hot water.
But if your thermostat is also acting as a timer, a fault with it might cause your boiler to shut off entirely, also starving you of hot water and plunging you back into an age so dark you feel blindfolded.
Cost to fix (and get your hot water back):
DIY: £0.00
Note: Thinking about an immersion heater instead? Read our guide to find out how they compare to combi boilers.
#2 - Boiler or pipe leak
A leaking boiler or pipe will most likely lead to a pressure drop, which you can read about in almost perverted detail in this boiler pressure article.
This leak will result in an inadequate water pressure level affecting the delivery of hot water to your taps. Instead of showering, you’ll either have to bathe in the puddle of leaking water next to your radiator or fix your boiler.
General losses of boiler pressure can be resolved by topping up your pressure manually but if this is caused by a leak, then this will need to be addressed by a professional.
As the pipe repair experts over at Fantastic Plumbers mention "most leaks occur at joints or fixtures i.e. the visible locations, so are quite quick and easy to fix. Common areas for leaks include the entry points that run into radiators".
Fun and completely made-up fact: the most uncommon area for boiler leaks turned out to be the southeast corner of the Mojave Desert.
Want to save money and energy on your heating bills? If so, you should consider installing one of the best smart thermostats.
Cost to fix (and get your hot water back):
DIY: £0.00
Engineer: £100-300
#3 - Energy source failure – gas or electric
A lack of either electricity or gas to the boiler is the most obvious and common reason for lack of hot water and will result in you being officially declared a silly sausage for Googling why your boiler is not working.
We won’t go into comprehensive detail about how to check if you have a gas or electric supply but start by checking other nearby appliances aren’t affected, be it lights or a gas cooker.
Oh – and not forgetting to check if your boiler is switched on to start with. Calling a technician to plug in your boiler is the worst kind of charity.
Cost to fix (and get your hot water back):
DIY: £0.00 (unless you've failed to pay your energy bills)
Engineer: £50-300
#4 - Inadequate water cylinder size
If you’re not getting hot water from your regular/system boiler then it might be that the cylinder isn’t adequate for your hot water requirements.
Cylinder sizes range greatly with smaller ones being suitable only for houses occupied by up to two Hobbits with a much smaller hot water demand.
If you’re fond of particularly lengthy showers as you wash away the sins of your poor boiler buying decision or you’re a family of standard-sized humans then your hot water will run out in no time.
Learn all about combi boilers in our what is a combi boiler guide.
This leaves you only three options: cold showers for your worst-behaved kids, shorter showers for everyone, or a bigger tank.
Cost to fix (and get your hot water back):
DIY: Impossible
Engineer: £500-700 (+ fitting)
Getting no hot water from your boiler? Here's a skim-readers conclusion
Having no hot water from your boiler comes with a diverse range of suspect reasons, that could cost anywhere between nothing and a small fortune depending on which company you approach to resolve the issue.
The most important thing to remember when you've got no hot water
#1 - If you’re not getting hot water from your boiler – explore every possible free/DIY fix (mentioned above). After exhausting these, educate yourself on the most likely reasons why your boiler's not working before consulting professional help so you’re aware of what you should be being charged – not what spanner-wielding joker fancies charging you for Friday afternoon.
#2 - If your boiler requires a costly repair, consider the age of your boiler and the likelihood of the boiler having further issues in the near future, and how important hot water is in your life.
If your boiler is 10 or more years old and has problems associated with age/corrosion, such as a faulty diverter valve, or regular leaks, consider a new boiler.
Can’t afford that? Check out boilers on pay monthly plans, with no deposit or 0% options.
For a massive article on prices, check out our new boiler costs article.
Curious to know which boiler brand performed worst? Find out in our report of the worst boilers.
Join Thousands of Satisfied Customers:
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#2 - Frozen pipes
'Big' boiler brands can stop giving hot water too
On the off chance your boilers manual isn’t your favourite book - here are some common error codes for common types of boilers.
No hot water from Worcester boiler
Error code | No hot water reason |
A1 | Water leak in pump |
EA | No flame (pilot light) |
FD 231 | Mains power fault |
F0 238 | Valve error |
356 | Low voltage |
EA 229 | Condensate pipe frozen |
356 | Low mains voltage |
Applicable Worcester Bosch boiler models:
Worcester Bosch CDi Classic, Worcester Bosch CDi Compact, Worcester Bosch Greenstar i, Worcester Bosch Greenstar Ri. Worcester-Bosch Greenstar 2000, Worcester-Bosch Greenstar 4000, Worcester-Bosch Greenstar 8000
No hot water from Vaillant boiler
Error code | No hot water reason |
F.24 | Pipe blockage |
F.29 | Pilot light failure |
F.61 | Valve failure |
F.21 | Pilot light not lighting |
Applicable to Vaillant models:
Vaillant EcoTec Pro, Vaillant EcoTec Plus, Vaillant EcoPure, Vaillant TurboMax.
No hot water from BAXI boiler
Error code | No hot water reason |
H.01 | Connection failure to gas |
H.03 | Pilot light failure |
E.01 | Frequent pilot light fault |
F0 238 | Valve error |
356 | Low voltage |
EA 229 | Condensate pipe frozen |
356 | Low mains voltage |
No hot water from Ideal boiler
Error code | No hot water reason |
F1 | Water leak in boiler/system |
Ideal boilers tell you literally everything else on the screen.
If you read the entirety of this article, you’re now endowed with an online PhD, majoring in the theoretical depths of ‘no hot water from boiler’. Feel free to draw yourself a certificate.
It’s approximately as useful as a British Gas customer service advisor but does afford you the freedom to confidently wear a tweed jacket with leather elbow patches.
The end of your tether? Where next? 👻
You may need a new boiler.
You may need it fast and with affordable monthly payments.
You may even need it from a company with top end local engineers, with 10,000 Trust Pilot reviews to back them up. Plus a Which? Trusted Trader award for good measure.
You may need a new boiler quote from us, Heatable 😘
