Short answer: HL is a high-limit/over-temperature warning. Treat it as a safety code, not a casual reminder. Do not enter overheated water.
Contents
What HL usually means
On Arctic Spa systems, HL can point to a high-limit condition at the heater or an over-temperature condition in the spa water depending on the model/controller. Either way, the safe response is the same: cool the spa, avoid use, and troubleshoot the cause before running it normally.
Safe first checks
- Do not use the spa while overheating is possible.
- Remove the cover and let heat escape.
- Confirm the water temperature with an independent thermometer if possible.
- Check filters and water flow once safe.
- Reset power once only after cooling.
- If HL returns, call for service.
How filters can contribute
Low flow can make heater-area temperatures climb faster than expected. That is why filter restriction belongs on the checklist. Clean or replace filters that are clearly restricted. If you are repeatedly fighting filter-related flow problems, review the filter replacement guide and compatibility guide.
Do not confuse HL with normal heat
A spa reaching the temperature you set is normal. HL is different because the controller believes a limit has been exceeded or a high-limit safety condition exists. If the code returns, the spa is telling you something is wrong — not just warm.
Related guides
FAQs
What does HL mean on an Arctic Spa?
HL is a high-limit or over-temperature warning. It can refer to overheated water or heater-barrel temperature depending on the controller/message.
Is it safe to use the spa with an HL code?
No. Do not enter water that may be overheated. Remove the cover, allow cooling, and troubleshoot only when safe.
Can filters cause an HL code?
Restricted flow can contribute to heater temperature problems, so filters are worth checking. But HL can also involve sensors, heater control, or service-level issues.
How do I reset an HL code?
Turn the breaker off for 20–30 seconds and restore power once after the spa has cooled. If HL returns, do not keep resetting it.
Should I call a technician for HL?
Call a technician if the water is overheating, the heater area is suspect, or HL returns after safe cooling and one reset.
References
This guide is an independent aftermarket support resource. Spa Filter Adapter is not affiliated with or endorsed by Arctic Spas. Official Arctic Spas support/manual pages were used as references and linked nofollow below.