Caravan Water Heaters – Everything You Need To Know

What are your caravan water heater options?

Navigating through a plethora of caravan water heating options to find the one for you can be an intimidating task. There is not only what size tank to consider, including having no tank at all, but which of the 3 common power source systems you are going to use.

In this article we will analyse your caravan and motor home water heating possibilities in a straightforward manor that takes out all of the technical sales buzzwords that you see on most caravan water heater supplier websites.

What sizes do they come in?

The size of your caravan or motor home, as well as how many people often use it would be factors when deciding what size water heater to get.

Smaller caravan boilers can hold around 5 litres of water, whereas the common size range is between 10 and 15 litres. The lower end of this scale would generally be more suitable for single people and couples that do not need to use much water each day. Larger varieties can hold over 50 litres, but these are more suited to the larger RVs often seen in the United States, or those of us that are partial to an on-board bath!

If you own a large caravan, it does not necessarily mean that you will need a water heater that is in proportion. Although they will need refilling less frequently, having a large water tank can take up a lot of space that could be used for other purposes such as storage. Also, if you do not use the water in the tank for a few days, bacteria may start to contaminate your water, so it is advised that you go for a tank that provides enough warm water for your needs only.

Tank and Tankless Water Heaters

Nowadays, you have the option to have a water heater that either has a tank or does not.

Tank based water heaters have been the most common for decades. They have often been powered by gas, and generally range between 5 and 15 litres, although electric only and combination variations are now available. We will discuss power source options in the next section.

Caravan Combi Boilers

Combination (combi) boilers are efficient water heaters that heat water only when it is needed, meaning you do not need to store it in a tank and heat the whole capacity every time you need some warm water. Although they are often described as cost efficient, and come with a range of benefits, such as faster water heating, there is a considerable initial cost associated with this type of heater.  You may find they range from around £400, all the way up to £3000.

Some of the benefits of combi water heaters include:

  • Energy savings, due to less water needing to be heated each time
  • Better for the environment, due to less energy being wasted in each heating phase
  • No wait times for the water to heat up
  • Limitless supply of hot water (assuming there is a cold-water source!)
  • Easier to alter water temperature as the whole tank is not already at a set temperature

There are 2 main costs to consider:

  • Up-front costs, as combi boilers are typically at least double the price of traditional tank-based systems
  • Potential problems with water flow when warm water is being used simultaneously in 2 or more devices

Water Heater Power Source Options

There are 3 main power source options to consider when deciding how to heat your water on your travels.

Most caravaners in the UK rely on propane gas, but some caravan water heaters are electric only, with some utilising both.

For those looking for a renewable energy source that can also be harnessed on the move, another option available is a solar-assisted hot water system. These higher-tech systems harness electric energy from photovoltaic cells by converting sunlight into electricity. Often in the UK, these would need to be supported by gas or a battery, due to the consistently inconsistent climate that we know and love!

How Much Do Caravan Water Heaters Cost?

Caravan boilers do not often require you to break the bank to get a warm shower on your travels.

Gas heaters between 5-10 litres can range from £100 – £400 depending on the brand. You could pay more, but this wont always be necessary to cater for your needs.

Electric only water heaters are not currently seen as often in the UK but are still available at the lower end of the gas price range. They often take longer to heat the water and require that you are connected to a 240V mains or take a leisure battery with you on your travels. However, due to the lower voltage associated with leisure batteries, you will probably need to charge the battery at regular intervals.

Compact boilers are much more expensive, sometimes topping £1000, although around £600 is more common.

How Much Does Water Heater Installation Cost?

To some people, installation may not be much of a troublesome task, but for those that need to hire someone to install the water heater, you should not expect to pay much more than £100 for a straight swap of water heaters. This process is relatively straightforward for a trained professional, but if you are changing your power source in the process it can be a more complicated task.

Depending on the supplier of your system, installation may also be included in the price.

How To Choose a Water Heater

There are several factors to consider when deciding what water heater to choose. These include:

  • The number of people that will often be using the water
  • How quickly you need the water to be up to temperature
  • If you have a preferred power source
  • Your budget

The most common water heaters in the UK use propane gas. G does come at an added expense, but this should not be too costly unless you have a large touring family and use it plenty and often.

Gas heaters generally will heat the water quicker than electricity. This would be something to consider if you do not wish to use gas on your travels.

Another thing to consider is how much you will be touring with the caravan away from a dedicated electricity hook-up. If you often go free camping you might consider a gas water heater since they can continue heating your water when off-site. You can use a 12V leisure battery for your electric heater, but since it takes lot of power from the battery, many people prefer to use gas if they are not near 240V AC mains.

How Long Does a Caravan Water Heater Take to Heat Up?

The short answer is probably around half an hour.

There are of course variables that can alter this estimate, with the main ones being the power source that is used to heat the water, and the size of the tank.

For an average 10 litre tank, electric heaters will usually get the water up to temperature within 45 minutes. Gas heaters can do the job quicker, with an estimate of around 30 minutes being more accurate. With combined power sources you can get the best of both, often reducing the heating time to between 15 and 25 minutes.

Tankless water systems do not have a tank (funnily enough), so there is not a wait between turning the heater on and getting warm water. With these types of systems, a gas burner or electric element heats the cold water as it flows through the unit.

How To Repair a Caravan Water Heater

When buying a new caravan water heater, it is important to understand that it is unlikely that you will never have any problems with it for the rest of your caravanning days.

Water heaters generally have a life span of 6-10 years. This is the kind of time frame that you should probably expect that you would have to repair it or buy a new one.

To troubleshoot your malfunctioning water heating system you should first check for gas or electrical supply issues. You might start by checking if your other appliances that reply on the same power source are working.

Next, check your regulator pressure. If it is at your ideal measurement listed in your user guide, there may be an obstruction that is causing your system to fail. Click here for additional advice for troubleshooting your caravan’s gas powered hot water.

Before replacing an electric caravan water heater in its entirety, you might want to check if the element is the issue, as sometimes, the elements are the root cause of many electric water heater failures.

To troubleshoot this, you should start by identifying whether your circuit breaker is off. This should be your first port of call as it might have tripped or been turned off. If you are sure that the circuit breaker is not the issue, your next steps should be to reset your water heater.

How To Reset a Caravan Water Heater

If you have a reset button on your water heater, you should find it around the temperature cut-off.

If you do not have a designated reset button, you could just turn the water heater off, leave it for at least 15 seconds, before turning it back on again. If you find that the heater trips again when you turn it back on, it is possible that the element within the heater is the cause of the malfunction.


Here in the UK, having a water heater for your caravan is more or less essential. If you have an external washing facility on the campsite, you could use your gas hob for water heating at small volumes. Saying this, you probably would not have read this article in its entirety if that was an option for you.

Navigating the wide range of options for your caravan water heater does not have to be difficult when you know what you are looking for. This article has aimed to break down the decision-making process into three aspects.

  1. The power sources available
  2. Whether you want a tankless system
  3. What size tank might suit your needs

Once you have one or two of these decisions made, it greatly reduces the overwhelming number of options you have to choose between. If this article has helped you narrow down your list of possibilities, it would be great for us if you could share the article to your social pages by clicking the share button here.