Home Improvement

No Heating or Hot Water? Here’s Why and What You Can Do

It’s a cold winter day – perhaps even the coldest day of the year.

You leave the comfort of your bed and blankets to make a morning cuppa, only to be welcomed by the same conditions you’d find in an antarctic glacier. Perhaps a nice, hot shower will warm you up? Guess again – you’re basically bathing in North Sea water.

You start to wonder what happened to your heating system. Why are the central heating and hot water not working? How can you fix the issue? Don’t worry – we’ve got the answers you seek!

Table of Contents:

So, if you’ve ever:

  • Come out of a steaming shower and into a freezing room;
  • Gone for a shower and been blasted by ice-cold water;
  • Had both your hot water and heating fail you at once,

Then keep on reading! This post is for you.

There are three possibilities here – either you have no heating and hot water at all, the hot water’s working, but there’s no heating, or there’s no hot water, but the heating is ok. So, let’s go over each of these issues and their causes.

There’s no heating and hot water

There are quite a lot of things that could have gone wrong if this is the case. It can be challenging to pinpoint the exact issue; however, your boiler should help you out by showing an error code. Unfortunately, that’s not always the case.

Let’s take a look at the many possible causes.

Check the power supply

Naturally, the first thing you should do is check if your boiler’s actually on. If not – is there an issue with the power supply? Is there electricity in the rest of your home? Was there a power outage recently? If there was, it might have messed with the boiler settings.

If you find that the power supply is the culprit, there are several possible reasons, which include the following:

  • A blown fuse
    If the fuse has blown, possibly due to a power surge, then you just need to change it, as your boiler won’t work without one.
  • A tripped RCD
    Look at your fuse box and see if all the switches are in the same position. If not, the RCD may have tripped. This can often occur after a power outage or in terrible weather.
  • A failing PCB
    The PCB (Printed Circuit Board) is the part that communicates with other boiler parts, such as the pump, valves, etc. If there’s no power to your boiler, it might have failed. To diagnose this issue, you’ll need a boiler engineer to take a look and determine if it’s just the PCB that’s faulty.
  • A broken fused spur
    A fused spur isolates big electrical appliances from the mains supply. It’s a socket with a small red window. So, if your boiler’s connected to a spur and is getting no power, the spur fuse might need changing.

Is there an interruption in the water supply?

If there’s no water reaching your boiler, then it can’t really do its job. This issue is easy to diagnose, as you probably won’t have water anywhere in your home, either. Unfortunately, there’s not much you can do, and you’ll have to just wait it out until the water supply is restored.

There might be an issue with the fuel supply

If you have no heating or hot water, no fuel may be reaching your home and boiler. If you’re connected to the gas supply, check if your other gas appliances are functioning correctly. If not, check to see if your supplier is still providing fuel. If you have an oil boiler, you might have run out of oil – check the storage tank.

Check the heating pump

Boilers have a flow and return pipe. The flow pipe takes hot water out of the boiler, so it should be hot to the touch. The return pipe, naturally, returns the water to the boiler after it’s made its way around the property. It should be a bit cooler, as water loses some heat along the way. If neither of these pipes is hot, or even warm, the issue might lie in the pump.

The condensate pipe may be frozen

If the weather is especially chilly and you find yourself with no hot water or heating, you might want to check if the condensate pipe is frozen. The flue gases that make their way out of your property through the pipe are prone to freezing in extreme conditions. Luckily, this is an easy fix. All you need to do is locate the condensate pipe, then thaw it. Pour hot, but not boiling water over the pipe until it thaws out. Then, check it for blockages and remove them if any.

Check the boiler pressure

The pressure on your boiler gauge should be between 1 and 1.5, maybe up to 2 bar when it’s not in use. If your boiler’s losing pressure, it won’t be able to heat the water properly, or it may have shut down because there’s too little water in the system, resulting in your central heating and hot water not working. Check if there’s any water leaking from the boiler. That would be the problem easiest to spot, but unfortunately, not the easiest to fix.

You may also like:
Home Improvement
How to Repressurise a Boiler

Is the pilot light on?

Some boilers have a pilot light – a small, constantly burning flame, which fires up a larger one when the boiler needs to provide hot water or heating. If the pilot light goes out, the boiler won’t be able to fire up and serve its purpose.

Unfortunately, that’s not something you should tackle on your own. You’ll have to call a Gas Safe engineer to handle any gas boiler related issues. Not to worry, though, we can help you with that. Find a certified boiler engineer to fix your water heater here.

Your timer or thermostat may be faulty

If you have no heating or hot water, you might want to check your programmer or thermostat, as that could be the culprit.

Set your thermostat to a higher temperature and see if the boiler fires up. Check that all the settings are correct, including the time. If there has been a recent power cut, it might have affected the settings.

Sometimes, you can fix thermostat issues with a reset. Consult the manual on how to do that. If your thermostat isn’t working and is not hard-wired, then a battery change might be in order. If you can’t seem to fix it at all, call a professional to take a look and determine whether it can be repaired, or if it needs replacing.

You may also like:
Home Improvement
My Thermostat is Not Working. What Should I Do?

So, there you go – if neither your heating nor your hot water is working, these are some reasons you might want to keep in mind. Let’s move on to the next issue – what if…

There is hot water but no heating

If you find yourself in a freezing room after a nice, hot shower, then there’s probably an issue with your heating system. There are a few possible reasons in this case – it’s either your radiators, your boiler settings (both heating and hot water should be on), or the diverter valve.

Let’s take a look.

Check all the radiators

The first thing on your checklist when you have heating, but no hot water, is to examine your radiators. Are all of them cold, or is it only a few? If even one of your radiators is warm to the touch, then the issue is most certainly not in your boiler.

If only some of your radiators are cold, there are a few possible causes. If they’re cold at the top, then there’s air in the system that needs to be bled out. Find out how to bleed your radiators in our helpful post. If your radiators are cold at the bottom, but warm at the top, sludge has built up in your system, and you’ll need a power flush.

You may also like:
Home Improvement
Do You Need a Powerflush? How to Powerflush a Central Heating System

If the radiators are cold all over, you might want to check if the valves are faulty, or if the pump is working properly.

The diverter valve might be broken

The diverter valve is what switches heat between your central heating and water supply. Naturally, wear and tear can get to it, resulting in a variety of issues. If your diverter valve is faulty, it won’t be able to switch positions. This means that either your heating or your hot water won’t work, while the other one does.

If you find the problem is not in your boiler settings or radiators, then it’s more than likely that it’s the diverter valve that needs changing. You’ll need to call a professional to get this done, though. Trust us – the cost of expert plumbing repairs is worth it.

Keep your home and your heating system safe – find an expert to handle your boiler repairs!

So, that’s something to pay attention to when your hot water is working, but there’s no heating. But what if it’s the opposite?

There is heating but no hot water

If your home’s all warm and cosy, but you can’t go for a shower without turning into a block of ice, then there’s an issue with your hot water supply (obviously). There are a few simple checks you can do to determine the cause.

Check all taps and showers

Go around your house and check if all the taps and showers are getting hot water. If only one or two taps are cold, then the faucet or shower itself may be faulty, and your boiler is probably fine. You’ll need to change the tap or fit a new shower, though.

You may also like:
Home Improvement
How to Fit a Mixer Shower

There may be an airlock in the pipes

If you have no hot water, but the heating works, or if the water coming from the tap is sputtering, then there’s almost certainly air trapped in the water pipes. Luckily, that issue’s not difficult to handle. So, find out how to get the air out of your water pipes.

There’s a diverter valve issue

As we mentioned before, if the diverter valve gets stuck, then either your heating or hot water will stop working, depending on what position it’s stuck in. Again, we highly recommend you get a professional to help you out, unless you’re a certified technician yourself. If you want to find out more about diverter valves in general and how an expert would handle the issue, head on over to our post on the topic.

Struggling to get heating and hot water back?

If you don’t fancy spending the winter as an icicle, don’t risk your health and safety. Call the professionals instead, and get your heating back! The skilled plumbers at Fantastic Services are fully insured, certified, and capable of tackling any issue that may arise.

Whether you need your boiler or radiators repaired, or even a full central heating power flush, we’ve got you covered! So, contact us now to arrange your service with our online booking form.

Are your central heating and hot water not working?

Find a professional to bring the warmth back into your home!

Add a valid postcode e.g. SE1 2TH


  • If you have neither heating nor hot water, there could be a range of issues; these include the power supply, the water or fuel supply, the heating pump, the condensate pipe, the boiler pressure, the pilot light, or the thermostat.
  • If you have hot water, but no heating, the issue may lie either in your radiators or the diverter valve.
  • If there is heating, but no hot water, it could be because of a faulty tap or shower, an airlock in the pipes, or a broken diverter valve.
  • The safest way to deal with a faulty boiler is to call a professional engineer to handle the problem.

If you’ve found that something’s wrong with your boiler, head on over to our helpful post on the matter, where you’ll find out why your boiler is not working, what may be causing it, and how to fix it.


Was this post helpful to you? Did you manage to get your heating and hot water back? Let us know down in the comments!

Image source: Polly Ivanova Art

4 4 votes
Article Rating
Notify of
Inline Feedbacks
View all comments
Would love your thoughts, please comment.x