Hot Tub Error Codes: What They Mean & How to Fix Them

Hot tub error codes can be confusing — one minute you’re ready to relax, the next your display flashes FLO, OH, Sn1, or something else.

This complete guide covers the most common hot tub error codes for all major spa pack brands, what you can try yourself, and when it’s time to call in the experts.

Balboa Hot Tub Error Codes

Balboa is one of the most common spa pack brands in the UK. Here’s what the codes mean:

• OH / OHH / OHS – Overheat
  Water temperature too high (110–118°F / 43–48°C).
  • DIY: Remove cover, let water cool, check circulation.
  • Call Spafix: If error repeats – sensor or relay may be faulty.
• FLO – Flow Problem
  Water flow insufficient.
  • DIY: Top up water, clean filters, bleed airlocks.
  • Call Spafix: If FLO persists – pump or flow switch may need replacement.
• DR / DRY – Heater Running Dry
  Circulation issue or low water level.
  • DIY: Refill spa, check pump/filter.
  • Call Spafix: Persistent error suggests pump/sensor fault.
• Sn1 / Sn3 – Sensor Errors
  • DIY: Check wiring, restart spa.
  • Call Spafix: Sensor replacement required.
• Sna / Snb – Sensor A or B Failures
• SnS – Sensors out of balance (temporary or wiring issue).
• HFL – Flow difference between sensors.
• LF – Persistent low flow (5x HFL in 24 hrs).
• ILOC – Interlock failure (ozone/pump spike).
• Cool – Water temp 20°F below set point.
• ICE – Potential freeze condition.
• Pr – Priming mode (startup).
• Std / Ecn / SE – Operating modes (standard, economy, standard-in-economy).
• — – Unknown water temp.
• pd – Power supply on battery.

Gecko Hot Tub Error Codes

Gecko packs are another popular brand.

• FLO / FLC – Flow Switch Errors.
  • DIY: Clean filter, prime pump.
  • Call Spafix: If problem persists – pump/sensor fault.
• HL – High Limit Triggered (≥119°F).
  • DIY: Power off, allow cooling.
  • Call Spafix: If recurring.

• AOH – Temp in equipment compartment to high.

• FrE – Freeze Protection (normal in cold weather).
• Prr / Prh – Probe/Sensor Errors.

Gecko SP Codes

• SP-HR – Hardware error.
• SP-BR – Breaker setting to low.
• SP-IN – Input voltage low.
• SP-F1, F2 or F3 –  Fuse 1, 2 or 3 blown.
• SP-OT – Temp inside skirt high.
• SP-OH – Water temp over 112F.

Gecko RH Codes

• RH-HR – Heater hardware error.
• RH-NH – Heat failed.
• RH-NF – No flow in heater.
• RH-NC – Communication error.
• RH-HL: Heater hi-limit.

Gecko Accessory Error Codes

• P1, P2 or P3-ER – Pump 1/2/3
• CP-ER: Circ pump
• BL-ER: Blower
• O3-Er: Ozone
• A1/A2-ER: Aux. system
• FN-ER: Fan
• FB-ER: Fiber optic
• SC-ER: System learning

For hardware/electrical Gecko codes, always call Spafix – these require professional diagnostics.

Sundance Spas Error Codes

• FLO / FL1 / FL2 – Flow Switch Errors.
  • DIY: Clean filters, check circulation.
  • Call Spafix: If persists.
• HOT – PCB temperature above limit.
• ICE – Freeze condition.
• PnL – Panel communication fault.
• Sn1 / Sn3 – Sensor Errors.
• ILOC – Interlock failure.
• COL – Water 20°F below set point.
• HOLD – Panel pressed too often.
• — – “Watchdog” problem.

Jacuzzi Error Codes

• OH – Overheat Protection
• COOL – 20°F below set point
• FLO / FLO2 – Flow switch issues
• HOLD – Panel pressed too often
• HOT – PCB overheated
• ICE / ICE2 – Freeze protection
• PnL – Panel communication error
• Sn1 / Sn3 – Sensor errors
• —- – Watchdog error

Other Spa Pack Error Codes

If you own a less common hot tub brand, use this quick reference. For persistent errors, book a Spafix engineer – DIY fixes vary by model.

Applied Computer Controls (ACC) Error Codes

• CoLd: Temp in heater housing <40°F
• OH: Overheat (spa >108°F)
• HLoH: Hi-limit overheat
• SEoP/SESH: Sensor errors
• PSoC/PSoL/PSoH: Pressure switch open errors
• ToE: Timeout error

Brett Aqualine Error Codes

• OH: Overheat >118°F
• Fr: Freeze condition (<40°F)
• FL: Pressure switch fail
• EO–E7: Sensor/flow/electrical errors

CTI Error Codes

• thl/39 / th2 / th3/39: Probe/temp errors
• OH / hot: Overheat >112°F
• HL: High limit switch

Dream Maker Error Codes

• OH: Overheat (108°F)
• FL: Flow switch issue
• SN: Temp sensor fault
• F2 / F4 / F6 / FC: Filtration cycle settings

EasyPak Error Codes

• FLO/FLC: Flow switch alarm
• FrEE: Freeze alarm
• HL: High temp
• Loc: Panel locked
• PrH/Prr: Temp sensor alarms

Hercules Error Codes

• OH: Overheat
• FLO: Flow problem
• ICE: Freeze condition detected
• SN1 / SN2 – Sensor errors

Hurricane Error Codes

• PS: Flow/pressure switch fail
• SH: Shorted sensor
• OP: Open Sensor Degrees
• LO: Temp below 60 degrees
• HL: Temp above 118 degrees
• OH: Spa temp exceeds limits
• FLO: Flow problem
• ICE: Freeze condition detected
• SN1 / SN2: Sensor failure

Pinnacle Error Codes

• OH: Overheat >110°F
• SN: Sensor failure
• FL: Flow switch stuck closed

Spa Builders Support Error Codes

• Sn1 / Sn2 – Sensor failures
• FL1 / FL2 – Flow switch errors
• COL / ICE – Cool/Freeze conditions
• OH – High temp
• — – Watchdog

Spa Quip

• err 1 (H20) / 09: Prime Failed
• err 3 / 01: Stuck Button
• err 4 / 03 / 04: Sensor Error
• err 5 / 05: Over temp
• err 6 / 06: Thermal Cut Out
• err 7 / 07: Stuck Relay
• err 8 / 02: No Data

Vita Spas

• HiLi: Water temperature over limit
• FP: Freeze protect
• BJ2P: Pump/blower purge
• SS / LS errors: Sensor/connection faults

Flashing Light Error Codes

• 1 flash: High limit fault
• 2 flashes: Flow switch short
• 3 flashes: Flow switch open
• 4 flashes: Open sensor
• Alt red/green flashes: Sensor/high limit fault

General Troubleshooting Tips

• Check water level & filters – low water or dirty filters cause many errors.
• Bleed airlocks – especially after draining/refilling.
• Reset the spa – turn power off for 10 minutes.
• Monitor temperature & flow – overheating/flow errors often link to circulation.

Need Help With Your Hot Tub Error Code?

Don’t let error codes ruin your soak. If your hot tub is still showing a fault after trying the DIY steps. Please contact the Spafix office team and we can arrange for an engineer to come out as soon as possible.

From sensor replacements to spa pack servicing and electrical diagnostics, our expert UK engineers get your hot tub back in perfect working order – quickly and safely.