Everything you need to know about caravan water systems
Technical advice
A complete guide to caravan water systems
Caravan water systems are essential for comfortable touring, delivering hot and cold water for cooking, cleaning and showering – just like at home.
Whether you’re a new caravanner or looking to troubleshoot your set-up, this guide covers everything you need to know about how caravan water systems work, what equipment is involved and how to maintain and clean it.
The lowdown: a caravan's water system can be split into three basic functions – pumping, switching the pump and heating the water.
Macaulay Nichol Content Editor: Caravans
Macaulay Nichol Content Editor: Caravans
How to get water in your caravan
Water in a caravan is typically supplied from an external caravan water barrel (like an Aquaroll), pumped into the system through a connected caravan water pump, then stored into an on-board caravan water tank and, lastly, distributed to taps and appliances.
Some caravans can also be connected to a mains water supply with the appropriate adaptors.
How caravan systems work
Water systems can be either manual, microswitched or pressure-switched.
The most common set-ups today use either a submersible pump or a diaphragm pump combined with pressure switches or intelligent controllers.
To help visualise the plumbing, refer to a caravan water system diagram (many manufacturers and guides include these online).
These illustrate how components like pumps, tanks, switches and valves connect.
Types of water pumps
Single submersible pump
Note: For simplicity we have omitted winter drain valves from these drawings
Here is a simple pressure-switched system using a submersible pump. The pressure switch acts as a one-way valve keeping the pressure in the system when the pump switches off. The other one-way valve prevents warm water from the heater getting into the cold supply. This arrangement can be found on many Lunar caravans.
Microswitched systems dispense with the pressure switch and accumulators. A one-way valve can stop water draining back into the container.
Diaphragm pump
Diaphragm pumps act as their own one-way valves and often contain a pressure switch.
This arrangement can be found on many Swift caravans.
With fitted on-board tanks, water systems can become quite complex.
This is one of the simpler arrangements. The selector chooses between the two water sources, the isolator opens to fill the on-board tank.
The downside is that you have to manually operate the valves to fill and then use the on-board tank.
This ‘two pump, twin inlet socket’ arrangement is very user-friendly. You will find it on Swift Group caravans from 2011 where on-board tanks were fitted.
The tank can be easily topped up by switching the external pump on and off.
Water switches
There are two main types of pump activation:
- Microswitches – installed inside taps, activating the pump when the tap is opened.
- Pressure switches – respond to drops in water pressure when a tap is opened.
Intelligent pressure switches, such as the Whale Watermaster IC and Truma Ultraflow Smart Switch, adjust automatically based on usage and battery levels and shut off the pump if it runs dry.
Caravan water heaters
A caravan water heater provides hot water for washing and showers. Most models are dual fuel – running on both gas and electric. Key types include:
- Truma Ultrastore – a 10-litre heater common in UK caravans from 2000s onwards
- Whale Rapid Heat and Expanse – compact heaters with fast recovery times
- Alde Compact – combines water and space heating using a radiator system
- Truma Combi – an all-in-one space and water heater, now common in Swift, Bailey and Coachman caravans
Cleaning your water system
Knowing how to clean your caravan water system is essential for hygiene and performance.
- Empty your tanks and pipes.
- Use a caravan-specific cleaning product (such as Puriclean or Elsan).
- Fill the system with clean water and the cleaner.
- Flush through all taps and let sit for several hours.
- Drain and rinse thoroughly with fresh water before use.
This process should be done at the start and end of every season.
What to do when arriving on a campsite
- Fill your water barrel or tank.
- Connect the pump to the inlet.
- Prime the system by opening taps.
- Check for leaks and pressure.
- Turn on the water heater if hot water is needed.
Leaving a campsite
- Turn off the pump and heater.
- Drain down the system, especially in winter.
- Empty grey waste tanks.
- Store hoses and connections safely.
These steps prolong the life of your system and prevent frost damage.
FAQs
-
Can you drink caravan water?
Yes, if the system is properly cleaned and the water is from a potable source. However, many caravanners prefer bottled water for drinking.
-
How do I clean a caravan water system?
Use a specialist cleaner, fill the system, flush it through the taps, let it sit, and rinse thoroughly. Repeat regularly.
-
Can I connect my caravan to mains water?
Yes, using a suitable mains water connection kit (available from most caravan retailers).
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How do you get hot water in a caravan?
Via a gas or electric water heater – usually a Truma, Whale or Alde unit.
Final thoughts
Whether you're just touring for the weekend, or stationed on a summer getaway, understanding your caravan water system is essential to getting the most from your tourer.
From caravan water pumps to heaters and cleaning routines, this guide gives you the tools to keep water flowing and your adventures stress-free.
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