The quick answer
Before a freeze, verify water level, circulation and freeze settings. After thawing, inspect for leaks before normal operation.
Before freezing weather
Clear baskets, confirm normal flow, protect exposed components as directed and know power controls and valves.
During the freeze
Moving water reduces risk in exposed plumbing. Do not force frozen valves or use unsafe heat sources.
If power fails
The correct response depends on system design and whether lines have frozen. Get qualified guidance if draining procedures are unknown.
After temperatures rise
Inspect pumps, filters, heaters, chlorinators, valves and pipes. Stop if water leaks or the pump cannot prime.
Chemistry still matters
Cold water slows demand but does not eliminate sanitation. Test and rebalance after circulation stabilizes.