When to Winterise Your Hot Tub
Winterising a hot tub is an important task for homeowners who want to protect their spa during the colder months. The most ideal time to winterise a hot tub is usually during late autumn, October or early November, before the temperature drops below freezing point. This ensures that the hot tub is fully drained, cleaned and prepared before frost and ice set in.
If water is left in the pipes or pump during freezing weather, it can expand and cause the hot tub to crack or leak. By winterising the hot tub before the temperature consistently hits low levels, you minimise the risk of damage and mechanical failures. Preparing the tub early also means you avoid working outside in uncomfortable conditions during cold or frosty weather.
Drain the Hot Tub Completely
The first step to winterise a hot tub is to check the water’s pH balance before draining it completely. This process sets the foundation for protecting the hot tub throughout the colder months, since it helps eliminate leftover chemicals, bacteria, and standing water that could otherwise cause damage while the tub remains unused.
It's highly recommended to test the water’s pH and sanitiser levels before draining the tub, since it ensures that any residual bacteria are broken down and the pipes and internal components are as clean as possible.
Once the water is balanced, the next step is to drain the hot tub completely. This step is vital because leaving any water inside the shell, jets, or plumbing can be extremely risky during freezing conditions. Any trapped water can freeze and expand, which can cause the pipes, pumps or fittings to crack. By fully draining your hot tub, you remove the biggest threat to its structural and mechanical integrity during the winter.
After draining the tub, many hot tub owners use a wet-dry vacuum to clear out any residual water from the jets and pipework. This extra step ensures that any drops of water that could freeze and cause damage are removed.
Clear Water from Pipes, Pumps and Jets
One of the most important parts of winterising a hot tub is ensuring that all the water is thoroughly drained from the pipes, pumps and jets. Even after draining the hot tub, small amounts of water can remain within the plumbing system. Water naturally expands as it freezes, and even a small amount of water that's left in a pipe or pump can cause cracks, leaks or damage to the fittings and seals.
Clearing the pipes, pumps and jets can prevent this damage and keep the system clean. Stagnant water that's sat in the plumbing for several months can also become a breeding ground for bacteria, mould or unpleasant odours. By removing the water completely, you ensure that the hot tub will be fresh and hygienic when you next use it.
Many hot tub owners use a wet-dry vacuum to force any trapped water out of the plumbing. This task can take a little bit of extra time and effort, but it makes sure that your hot tub’s internal system is fully protected from the cold winter conditions.
Clean the Shell, Filters and Add Antifreeze
The shell of the hot tub should be cleaned thoroughly after the water has been drained. Over time, oils, dirt, and chemical residues can build up on the surface of your hot tub, and if they aren't cleaned during winter, these deposits can harden, stain, or become difficult to remove. Using a non-abrasive spa cleaner to clean the shell helps keep it fresh and ready for use.
The filters can also collect debris, oils, and contaminants that can clog the system, and leaving dirty filters inside the tub during winter can shorten their lifespan and cause bacteria to grow. Properly removing, cleaning and drying the filters - or replacing them entirely - ensures that your tub is hygienic and ready to use during the summer.
Finally, adding antifreeze to the plumbing system also gives your hot tub an extra layer of protection. Even after draining and clearing out the pipes, small amounts of water can remain in hard-to-reach areas. During freezing temperatures, the water will expand and damage the pipes or fittings. However, non-toxic antifreeze can protect your hot tub against this risk.
The Hot Tub Engineer provides professional hot tub cleaning and maintenance services that are designed to keep your spa in perfect condition all year round. From deep cleaning and water balancing to filter maintenance and full system inspections, we make sure your hot tub is safe, hygienic and ready to use.
