How often should Alde fluid be changed?

Alde recommends a fluid change every 5 years under normal use. If you've bought a used caravan and don't know the service history, treat it as overdue and have it tested.

What does Alde fluid look like when it needs changing?

Fresh Alde fluid is a clear pink or blue colour. If the fluid in your expansion tank looks dark, murky, or brown, it's degraded and should be changed. Discolouration means the anti-corrosion additives have broken down.

Can I change Alde fluid myself?

Some experienced owners do change their own Alde fluid, but there are good reasons to use a professional: correct disposal of old glycol fluid, accurate concentration testing, proper air bleeding, and spotting any system issues at the same time.

How much does an Alde fluid service cost at Blue Sky Caravans?

An Alde fluid change with Blue Sky Caravans is from £225. This includes a full system drain and flush, genuine Alde 5-year antifreeze fluid, bleed and pressure test, and a heating output check.

Should You Check Your Alde Fluid Before Winter?

As temperatures drop, caravan owners with an Alde wet heating system have one job to add to their winter checklist: check the heating fluid. It's a small thing that gets overlooked, and it's one of the more expensive mistakes to make when you're on a cold campsite and the heating isn't working.

1. What is Alde fluid and what does it do?

Alde fluid is a glycol-based antifreeze solution that circulates through your Alde wet heating system. Unlike blown-air heating, Alde works like domestic central heating: fluid flows through radiators and underfloor pipes to provide gentle, even warmth throughout the caravan.

The fluid does two things. It transfers heat efficiently around the van, and it protects the system from freezing when temperatures drop. Both functions degrade as the fluid ages.

"Old fluid doesn't just heat less well. It corrodes the pipes, blocks the system, and can freeze. A fluid change is cheap insurance."

2. When does it need changing?

Every 5 years, according to Alde's own guidelines. The anti-corrosion additives in the fluid break down over time, and the antifreeze concentration degrades, leaving the system less protected.

If you've bought a used caravan and don't have a service history, assume it's overdue. A quick inspection of the expansion tank tells you a lot: fresh fluid is a clear pink or blue. If it's dark or murky, it needs changing.

3. Why does winter make it more urgent?

There are three reasons winter is the worst time to have degraded Alde fluid.

Freeze protection degrades over time

Old or diluted fluid may not protect down to the temperatures it claims on the bottle. If it freezes, the damage to pipes, radiators and the boiler unit is expensive to repair and not always covered by insurance.

Heating performance drops

Degraded fluid doesn't transfer heat as well. The system takes longer to warm up, radiators heat unevenly, and you burn more gas or electricity to stay comfortable. You might not notice in mild weather, but you'll notice at 2°C.

Corrosion accelerates

Once the anti-corrosion additives are spent, the fluid starts attacking the system from the inside. Sediment builds up, pipes corrode, and what starts as a fluid change becomes a repair job.

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4. Warning signs to look for

These are signs the system needs attention, whether or not the fluid is overdue:

! Heating takes longer to reach temperature than it used to
! Some radiators warm up while others stay cold
! Gurgling or bubbling noises from the system
! Fluid in the expansion tank looks dark, brown, or murky (should be clear pink or blue)
! Needing to top up the system regularly
! Error codes on the Alde control panel

5. What a proper Alde fluid service involves

A proper Alde fluid service isn't a quick drain and refill. As an approved Alde service partner, here's what we carry out:

Step	What it involves
System inspection	Checking for leaks and visible damage before draining
Fluid testing	Measuring antifreeze concentration and condition
Complete flush	Removing old fluid and any sediment from the system
Refill	Genuine Alde 5-year antifreeze fluid at the correct concentration
Air bleeding	Removing air pockets for even heat distribution
Pressure test	Confirming the system is sealed correctly
Function test	Running the system to verify performance before we leave

We carry genuine Alde fluid in the van and carry out the service at your home, storage yard or pitch. Old glycol fluid is collected for proper disposal — it's not something you can pour down a drain.