Troubleshooting guide
How to winterize a hot tub
A running, covered spa protects itself from freezing. Problems start when power fails or the spa sits unused. Here's what manufacturers recommend.
If you're using it all winter
Balboa's TP500S guide explains freeze protection: when sensors detect a low enough temperature, the pumps (and blower) turn on automatically, continuously or periodically. It's normal to see them run on cold days. Hot Spring adds that very cold, windy weather (below 10°F) can partially freeze a jet pump even when the water is at temperature, and an equipment-bay insulation kit from the dealer can help.
Power outage in freezing weather? That's when damage happens. Without power, freeze protection can't run. If the spa is going to be without power for a long time in freezing weather, contact a local spa tech promptly.
If it will sit unused in freezing weather
Hot Spring says if the spa will be unused for a long time in severely cold weather, drain and winterize it to avoid freezing from a power or equipment failure, and strongly recommends having a dealer do it. Its steps, summarized:
- Turn off power at the GFCI breakers, then drain the spa through the drain valve with a garden hose routed away from the foundation.
- Remove the filter, clean it and store it dry.
- In climates below 32°F, use a wet/dry shop vac to vacuum water out of every jet (top down), the filter suction fittings and compartment, and the floor drain.
- Dry the shell, replace the drain cap, and pour propylene glycol antifreeze into the standpipes, suction fittings and jet openings.
- Close and strap the cover, add plywood and a tarp to spread snow load, and reinstall the equipment door.
Opening it back up
Hot Spring's opening steps: remove the plywood and tarp, follow the normal start-up and refill steps without installing filters at first, and superchlorinate to break down the antifreeze before use. See airlock after a refill if the pumps don't move water.
Inflatable spas
Inflatable spas have their own cold-weather limits. Lay-Z-Spa's codes include E03 for water that's too cold. If you aren't using an inflatable spa in winter, follow the maker's drain, dry and storage steps; see inflatable hot tub error codes.
Common questions
Should I drain my hot tub for winter?
If you'll keep using it, a covered, powered spa with freeze protection usually stays safe. If it will sit unused in freezing weather, manufacturers like Hot Spring recommend draining and winterizing it, ideally by a dealer or tech, so a power failure can't freeze it.
What antifreeze is safe for a hot tub?
Only propylene glycol, the non-toxic type sold for RVs and boats. Hot Spring warns never to use automotive (ethylene glycol) antifreeze because it's toxic.
Why do my hot tub pumps run when it's cold outside?
That's freeze protection. Balboa explains that when sensors detect low temperatures, pumps and the blower turn on automatically to keep water moving. It's an operational message, not an error.
Related guides
Airlock after a refill
Just drained and refilled, and now no jets or no heat? Prime the pumps.
Read the guideInflatable spa codes (Lay-Z-Spa, Intex)
E02, E03, E04, E05 on Lay-Z-Spa, E90 on Intex: what they mean.
Read the guideCloudy or smelly water
Cloudy, foamy or smelly water: filters, sanitizer and pH first.
Read the guideHot tub not heating
Jets run but the water stays cold. Usually it's flow, not the heater.
Read the guideSources
- Hot Spring Spas (Watkins Wellness), Hot Spot collection SX/TX owner's manual: GFCI and high-limit checks, priming, drain & refill, winterizing and troubleshooting tables
- Balboa Water Group, TP500S / TP600 system user guide (42339 rev A1): priming mode, freeze protection, GFCI trip test and message codes
- Balboa Water Group, Spa Touch 3 user guide: panel messages, flow-related checks and reminders
- Lay-Z-Spa (Bestway) UK: pump error code index
Brand names belong to their owners. Hot Tub Helpline isn't affiliated with or endorsed by any manufacturer. Steps and codes vary by model and year, so always check your own owner's manual.