I know first-hand just how incredibly frustrating caravan water tank filling problems can be. They always seem to happen at the most inopportune times.
Like when you’re filling your water tanks at a public tap and there’s a line up of people behind you, but the water just keeps spurting back out, rather than actually filling up the tanks. Or, you just want to brush your teeth and get into bed, but the tap suddenly splutters dry. Or, when you’re camped in the middle of nowhere and can’t seem to access your 200 L of water because there’s an air lock in the system.
It’s certainly in those moments you think, “Remind me again why it is that I like caravanning so much?!”
I know it well.
So, I’ve done some research and compiled all of the information I could find about caravan water tank filling problems with troubleshooting tasks to try.
The purpose of this page is to gather as much information as is available on the topic in order to offer a (hopefully) helpful resource to others who find themselves in a water tank predicament.
If you have any tips or experiences that you can add, feel free to pop them into the comments at the bottom. You never know, your crappy experience may just be able to help someone else out!
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Caravan Water Tank Filling Problems
The Tanks Won’t Fill (even though they’re empty)
Sometimes, when trying to fill up the water tanks, water will keep spurting out of the tank filler, even though you know the tanks are definitely empty.
This is due to an air lock.
When filling the tanks, the water should be pushing the air that’s inside the tanks out through the breather tube. However, sometimes an air lock can happen, which will result in you frustratingly trying to trickle-fill the tank, despite knowing that there’s plenty of room in there for the water!
The problem is usually that the breather tube has become blocked.
- Water spurting out of the tank filler
- Water will only trickle into the tank (rather than flow in)
- Water bubbles and burps back out through the filler
- Check that the breather tube isn’t kinked or sagging
- Check for blockages at the breather hole or inside the breather (e.g. wasp nest or dust)
- Put your thumb over the breather hole for 5 – 10 seconds while filling the tank, then release it (this may help to ‘push’ the air lock out)
- Open up any additional filler holes to help release trapped air locks
- Fill the tanks slowly, which should help to push the air out of the system
- Try pushing the hose further down into the tank while filling
- Attach an extension to the end of your hose so that you can get closer to the tank
Never fill water tanks with a high-pressure hose as it can encourage air locks by not giving the air enough time to escape through the breather. Regular household pressure is better.
Adding a Hose Extension
Another issue is that some caravan fillers come out lower than where the water tank is sitting. In other words, the water has to make its way down and then back uphill before entering the water tank.
One solution is to add a long piece of irrigation pipe to the end of the hose you’re using to fill up the water tanks. This way, the hose can be fed down into the filler intake pipe and get closer to the water tank.
The video below demonstrates this method really well.
▶️ VIDEO: Add an extension to your water filler hose ↓
Adding a Secondary Tank Filler & Breather
If you’ve only got one water tank filler and breather for multiple tanks, you may find that that’s the cause of the water spurting back out, rather than filling the tanks.
In the video below, an extra water tank filler and breather were added, which solved the problem. This isn’t an easy solution and requires some modifications, but if you’re handy on the tools, it may just work for you.
▶️ VIDEO: Add an extra tank filler & breather ↓
Sometimes when you’ve got the water pump turned on and you are (trying) to use your tank water, the taps will start to splutter and not release any water.
The first port of call is to make sure that you’ve still got plenty of water in your tank/s. If the answer is ‘yes,’ then you’ve got air in the system somewhere.
A common issue can be a kinked or blocked hose, which can cause a small air leak to occur. Air can leak into the system either between the tap and water pump or between the water pump and water tanks, causing the spluttering.
- Tap splutters when turned on
- Little to no water is coming out of the tap
- Check that none of the water hoses are kinked (causing air to enter the system somewhere)
- Check that all hoses are connected properly (sealing out any air ingress)
- Check that the 12v pump is working properly
- Check that there’s enough power in the batteries to power the water pump
- For multiple water tanks – ensure all link taps are open (to allow water to flow into the one powered by the pump)
- For multiple water pumps – ensure each pump is being powered & working correctly
- For manually operated (hand or foot) water pumps – may need to replace the seal
If you’ve got a manual water pump, make sure you use the water system every few months to avoid having the seals dry out.
How to Permanently Avoid Air Locks
Here are some solutions people have come up with to more or less avoid air locks during the tank-filling process.
Fill Tanks from the Drain Hole (underneath the van)
Some caravanners swear that the best way to avoid air locks in the first place is to fill the tanks from the same place that it drains out of.
In other words, the point underneath the tank where you’d usually open a bung to let the water drain out of now becomes your new filling point.
In order to do this, you will need to attach connection points so that you can hook up a hose for filling.
The best part of using this method to fill water tanks is that the air that is sitting at the top of the tank will naturally be pushed out of the breather as you’re filling it from the bottom. It helps to also open the original water tank filling point (up near your breather), to allow an extra opening for the air to escape.
If you do opt for this method, be sure to get a cap or bung to close up your new fill point when not in use. This will stop bugs and wasps from crawling in and nesting.
Benefits of Filling from the Drain Hole:
- Air gets pushed out the top of the tank while you fill it from the bottom
Use a Stand At Ease Water Tank Filler
There are a few pros to using a Stand At Ease to fill your caravan water tanks.
Firstly, it easily attaches to any normal hose for use.
Secondly, the design of the gadget means that the end of the Stand At Ease sits well down inside the water tank filler hose, which seems to stop air locks from happening. Maybe it’s due to the fact that water is no longer trying to splutter back out of the filler hole, which can add pockets of air into the filling process. Instead, the water funnels directly down into the tank without any issues.
The third pro with using a Stand At Ease is that you are able to fill the tanks quicker and more easily with a bit more pressure. Since it slots right down into the filler hole, you can set the hose in place and walk away, rather than having to stand there fussing with the hose the whole time.
Stand At Ease Benefits:
- Can fill tanks without holding onto the hose
- Hose goes further into the filler hole, reducing the chance of air locks
- Can fill tanks quicker
Now that you’ve got your water tank filling problems sorted, it’s time to find out how to clean the water tanks, including which product is the best.
If you’ve got any expertise you can add to this list, feel free to add them into the comments down below.
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