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What to do if you have no hot water or heating

What to Do If You Have No Hot Water or Heating

If you have no hot water or heating in your home, chances are that the boiler is at the root of the problem. Having no hot water in the house can be seriously disruptive to daily life and the heating not turning on during the winter can also be massively inconvenient.

Why Do I Have No Hot Water?

Simple tasks such as doing the dishes and having a wash can become much harder than they need to be. Thankfully, there are many common potential reasons why you may have no hot water or heating that can often be resolved quickly.

Things to Check First if There is No Hot Water in House:

If your home is suddenly not getting any heating or hot water, there are a few things to check first. Make sure that the power supply to your boiler is switched on. If your boiler has been accidentally unplugged, this could be a very simple reason for why the hot water and heating isn’t working.

You can also try resetting the boiler by turning it on and off again or using the reset button. This can work in some cases, especially if the boiler is showing any redundant fault codes that are preventing it from operating.

Check your gas main to make sure that the fuel supply is open. If it is closed, this will prevent the gas supply from reaching the boiler and heating your home and water.

Finally, check that you have selected the right program on your boiler or thermostat. If your hot water depends on a timer, make sure that the time is set correctly, especially during the times of the year when the clocks change.

Common Combi-Boiler Problems That Lead to No Hot Water:

Low Boiler Pressure:

One of the most common reasons for no hot water in the house is a low boiler pressure with a combi boiler. The system must be pressurised to around 1-1.5 bar in order for it to operate correctly. The boiler will not operate for central heating or hot water if it does not have adequate pressure. Low pressure is likely to be the culprit if the pressure gauge is indicating less than one bar. You can solve this problem by topping up the system via the filling loop. If your boiler is losing pressure frequently, it is usually caused by a leak in the system.

Diverter Valve Faults:

The diverter valve is a key part of your combi boiler which controls how the heat is used. Typically, domestic hot water will be the main priority. This means that if a hot tap is turned on while your central heating is switched on, the diverter valve will switch the boiler to providing heat for the tap water rather than water to the radiators. Once the hot tap is switched off, the boiler will return to heating your home. If you have a combi boiler and your central heating system is working as normal but you have no hot water, your diverter valve is likely to be at fault.

Boiler Breakdown:

Most combi boilers are prone to breaking down after around ten years of use. If the property that you live in has a boiler that is ten years old or more, it may be that the parts inside the boiler are deteriorating and need to be repaired or replaced in order for it to heat your hot water and the central heating system correctly. In some cases, the boiler may need replacing. If you have tried all the steps outlined in the video and your heating or hot water is still not working, contact Greater London Properties and we will send out an engineer to check your boiler and diagnose the problem.

What to Do if Your Hot Water isn’t Hot Enough:

If your hot water is only warming up slightly but not getting very hot, there are several potential reasons for this. if you have a combi boiler the water is heated on demand from the mains and any interference in this process is likely to have an effect on the water’s temperature. In some cases, all you may need to do is close the tap slightly to reduce the pressure, however, this is a sure sign that your boiler is struggling.

Firstly, check that the temperature setting on your boiler is set correctly. You can usually manually set the hot water temperature to tell the boiler how hot you want the water to be. If you only experience this problem during the winter, it is likely due to the fact that the temperature of mains water is lower and it takes much longer for the boiler to heat up when the tap is fully opened.

I Have Heating But No Hot Water

A faulty diverter valve may also be responsible for this problem, or it could be due to a build-up of sludge and limescale within the boiler which can prevent the effective transfer of heat. In this case, your boiler will need to be flushed by a qualified contractor.

What to do if you have no hot water or heating, By Greater London Properties

Hopefully this video helps explain what to do if you have no hot water or heating.  Greater London Properties over 24/7 Property Management for your rental properties, please give us a call on 0207 734 4062 if you have any questions. We welcome new landlords in London, please visit out website at

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