a guide to error codes
Modern hot tubs use sensors and control systems to monitor temperature, flow, filtration cycles, and other running operations. When the system detects something unusual, it may display an error code to protect the spa and prevent equipment damage. This guide can help!
*Disclaimer: The error codes listed in this guide are intended for general reference only. Error codes can vary significantly between hot tub brands, models, control systems, and manufacturers. The same code may indicate different issues depending on the spa's equipment configuration. Always refer to your specific owner's manual for accurate troubleshooting steps.
If you are unsure about a warning message or the issue returns after troubleshooting, please contact us at (604) 907-2646 to inquire further and/or book a qualified hot tub technician for assistance.
BEFORE TROUBLESHOOTING:
Turn the power off at the breaker.
Wait 30–60 seconds.
Restore power.
Check if the error returns.
Confirm water level and filter condition.
A simple reset may clear temporary errors, but recurring codes usually indicate an underlying issue.
Common Hot Tub Error Codes
FLO / FLOW / FL / FLC
The spa may be detecting insufficient water flow through the heater.
✓ Confirm water level is above the recommended line
✓ Loosen any air bleeders, purge pumps to remove air, retighten bleeders, and test if error code clears
✓ Clean or replace dirty filters
✓ Check that valves in equipment area are fully open
✓ Reset power at the breaker
OH / OHH / HL / HIGH TEMP
The system has detected overheating.
✓ Turn power off and allow the spa to cool with the cover off
✓ Lower filtration cycles for older pumps
✓ Clean filters
✓ Ensure water is circulating properly
✓ Lower water temperature for high weather temperatures
SN / SNA / SNB / SENSOR FAILURE / HI-limit
The spa has detected a sensor or high limit error, which may indicate temperature reading malfunctions or that an automatic heater shutdown was triggered due to overheating.
✓ Allow spa to cool with cover off
✓ Reset power
✓ Confirm the error returns
✓ Check for visible loose connections (without opening electrical panels)
ICE / FREEZE PROTECTION
The system has detected extremely cold conditions and activated freeze protection. The heater shuts down to avoid damage.
✓ Ensure power remains connected
✓ Confirm pumps are running & water is circulating
✓ Keep cover on securely
✓ Let it run its course!
✓ You may consider blow-drying the equipment area to help the pipes thaw
DRY / DR / HEATER DRY
The heater is running without enough water flow.
✓ Check water level
✓ Clean filters
✓ Loosen any air bleeders, purge pumps to remove air, retighten bleeders, and test if error code clears
✓ Confirm pumps are not gurgling
LF / LOW FLOW
Repeated flow problems have been detected.
✓ Clean filters
✓ Top up water level and confirm all jets are covered (not including fountain jets)
✓ Loosen any air bleeders, run pumps to remove air, retighten bleeders, and test if error code clears
✓ Check for blockages (in filter canister, skimmer)
✓ Confirm pumps are not gurgling and water is heating
PSI / PRESSURE SENSOR ERROR
The system cannot correctly read water pressure or flow.
✓ Check filters
✓ Check water level
✓ Reset power
COMMUNICATION ERROR
Control components are not communicating properly.
✓ Reset power
✓ Confirm all components restart
GFCI / BREAKER TRIPPING
The electrical system is detecting a safety issue.
✓ Reset breaker once
✓ Check for visible leaks around equipment
Do not repeatedly reset a breaker that continues to trip.
WATCHDOG / WDT / SYSTEM RESET
The control system has detected an unexpected problem.
✓ Power cycle the spa
✓ Confirm proper operation after restart and does not shut down repeatedly
Common Non-Code Problems
hot tub not heating
✓ Clean filters
✓ Confirm water flow
✓ Ensure you are in a “READY” or “STANDARD” mode (not “REST”/”SLEEP”/”ECON,”VACATION” modes)
✓ Loosen any air bleeders, purge pumps to remove air, retighten bleeders, and test if error code clears
JETS NOT WORKING
✓ Check water level
✓ Check diverter/air control valve positions & adjust
✓ Ensure valves in equipment area are open
Hot tub leaking/losing water
✓ Identify where water may be collecting (Check for wet ground, check equipment area for drips or wet insulation)
✓ Tighten loose plumbing connections
✓ Reduce use until inspected
When Should You Contact Us?
We recommend reaching out if:
An error code returns after basic troubleshooting
Your hot tub is not heating
The breaker continues to trip
You hear unusual noises from pumps or equipment
You notice leaks
Your water is not circulating properly
You are unsure what a code means
A control is unresponsive
There is no power to the spa
You would rather have a professional diagnose the issue before replacing parts
Sometimes a quick conversation can prevent unnecessary part replacements or help determine whether an on-site service visit is needed.
If you have an error code you don't recognize, send us a photo of your display, your hot tub brand/model, and a description of what happened before the error appeared—we're happy to help point you in the right direction.