Storing a pool robot where it freezes

Yes, freezing can damage a robot. The main cause is water left inside it.

One maker's guide explains it. Water inside the unit expands when it freezes. That can crack seals and internal parts.¹

The same guide says that leftover water is what causes freeze damage if the storage area gets cold.¹

That's the whole story in two sentences. Cold alone is one problem. Cold plus trapped water is a worse one.

What the makers' rules say

Maytronics lists frost among the things to avoid. Its lowest storage temperature is 5°C, which is 41°F.²

Another guide is stricter in its wording: "Never store where temperatures drop below 40°F (5°C)."¹ The two figures agree to within a degree.

Storage is only half the picture. Water temperature while the robot is still in the pool is a separate question, and the second page in this set covers it.

Two figures from two makers, then. Each is a floor, not a target. Your own manual may set the floor higher or lower, and it overrides both.

Is that only about the robot?

No. Maytronics also warns that "extreme weather conditions can harm the cleaner's electronics and reduce its lifespan".³ If you have a cordless model, there's a battery to think about. Follow the maker's instructions for its storage.

What to do if your winters freeze

1. Drain it completely. Maytronics wants no water left inside the cleaner.² The first pages in this set show how.
2. Dry it. See drying a pool robot properly.
3. Store it somewhere that stays above the lowest figure in your manual.
4. Store a corded model's power supply indoors in a dry place. iGarden says never to store it outside, even if covered.¹ Maytronics adds that it is splash-proof only and cannot be immersed.²

An unheated shed or garage

This is where trouble starts. An outbuilding follows the weather, so a night of hard frost can reach the robot. Maytronics says an outdoor store needs regular checks for moisture and temperature swings.³

A quick look inside on a cold morning tells you whether the place is holding up. If the robot is damp or the floor is wet, move it.

If the place can drop below the lowest figure in your manual, move the robot. iGarden says an uninsulated garage can drop below freezing in cold climates, and advises a basement or interior closet instead.¹ See where to store a pool robot.

What your manual says

Makers publish their rules in the user manual, often as a "storage" or "care" section. Look there for three things:

• the lowest storage temperature
• how to drain your model
• anything about the battery or power supply

If your manual and this page differ, trust the manual.

Thawing after a freeze

Say the robot got caught in a hard freeze with water inside. Don't power it up to see. Check your manual or call the maker's support line first.