Some of our members try to do this annually and as a result, they have provided some tips on the best method. It uses vinegar so it is both cheap and effective.
De-scaling is usually best done immediately after sterilising and draining the water system.
Before you start, ensure that the filter elements in the heater have been removed.
You will need about five litres of vinegar (check the cost per litre as it is sometimes cheaper to buy vinegar in pint bottles).
Dilute the vinegar down to 50% strength by adding five litres of water then pour the vinegar and water mix into your external water container.
Refill the caravan water system, eliminating all the air from the pipes.
Turn on the water heater at full temperature and let it run for several hours, please do not leave the caravan unattended during this time!
Now turn off the water heater and empty the system.
Re-fill the system with fresh water and empty it out again to rinse out all the vinegar.