Hot tubs these days are pretty advanced compared to the hot tubs of 20-25yrs ago. Evermore important to have a Hot tub repairs cheat sheet. That being said these advancements or improvements have made it easier for the homeowner to troubleshoot the spa themselves or at least confirm what the repair or service issue may be before having to pull out the toolbox. Most issues can be identified simply from reading the topside control panel and this cheat sheet should help if you refer back to it time to time when needed.
Hot tub repairs cheat sheet basics
The best hot tub repairs cheat sheets are made up of shortcuts or backdoor answers.
COOL message- The temperature of the water is 20 degrees below the set temperature. The low speed pump, circ pump and heater will come on and stay on until the water temperature reaches within 15 degrees of the set temperature. Typically this happens after you fresh fill your spa with fresh cool water from your garden hose spigot.
ICE message- Potential freeze condition (55 degrees) detected. Pump 1 activates then pump 2 activates after 10 seconds. Both pumps stay on for a minimum of 11 minutes or until the danger of freezing passes (65 degrees). Typically this happens after you fresh fill your spa with ice cold water from your garden hose spigot. The ICE message could also appear if the heat shutdown on your spa for a period of time that would allow the temperature to drop to 55 degrees. So in a nutshell if you have not just completed a fresh fill you will want to investigate further ie make sure your spa controls are setup for 24hr circulation, standard mode and you have a heat call programmed. The ICE message can pop up post another message such as the FLO message or flashing FLO message which we will talk about later in this Hot tub repairs cheat sheet.
SN3 message- Heater is deactivated. Temperature sensor is non functional. Typically this would mean you have a bad temperature sensor. Before you go ahead and replace the sensor however it is a good idea to check your connections where the sensor attaches to the PWA. Always replace your temperature sensor O-ring when you replace the sensor.
SN1 message- Heater is deactivated. Hi-limit sensor is non functional. Typically this would mean you have a bad hi-limit sensor. It is very rare for hi-limit sensors to fail so before you go ahead and replace the sensor it is a good idea to check your connections where the sensor attaches to the PWA. Also check that the sensor probe is inserted completely into the heater thermowell.
– – – – message- Otherwise known as the watchdog message. Four dashed lines means your hot tub is deactivated. The PWA thinks the spa temperature is 120 degrees F. The watchdog is typically caused by a bad temperature or hi-limit sensor, however the pwa, control panel, transformer, clogged filter, blown F1 fuse or electrical issues may also cause this condition. If you leave an ICE, SN3, SN1 or FLO message uncorrected long enough the – – – – message will surface.
The many faces of FLO message
There are 3 variations in the type of FLO message that can show up on your control panel: Flashing FLO, Solid FLO and Solid FLO2.
Flashing FLO message- Typically this indicates that the circulation pump should be on and that there should be flow yet the system is not detecting any. This can be caused by a soiled or dirty filter, plugged circulation pump, bad circulation pump, bad flow switch, bad PWA. If you leave a flashing FLO message uncorrected long enough you could end up with an ICE message alternating with the FLO message if the water dips to 55 degrees. This is quite common in the winter months when a soiled or dirty filter is left unattended.
Solid FLO message- Typically this indicates that the circulation pump should be off and the system is detecting a closed flow circuit. This message disables all spa functions. It is usually caused by a shorted flow switch. Possibly hair or debris keeping the flow switch paddle closed. It could also be a shorted circulation pump circuit or a bad PWA.
Solid FLO2 message- Typically this error message indicates a closed flow switch circuit upon startup. This message disables all spa functions except the ability of the spa to freeze protect itself. The problem must be corrected to clear this error code. Usually a bad flow switch. It could also be a shorted circulation pump circuit or a bad PWA. Confirm your wiring of the circulation pump before replacing the flow switch. It is possible hair or debris kept the flow switch paddle closed when it powered down. Sometimes if you re-boot the system the FLO2 message may go away but it usually comes back within a 24hr period. Sometimes the control panel may read a solid FLO message first when you power up and then the control panel reverts to a solid FLO2 message. The problem must be corrected to clear this error code. Usually a bad flow switch.
Heat & Flow
There can be a condition in your spa where heat and flow are working side by side to shut down the system. An error message OH appears on your control panel. This message typically means the heater is deactivated. Overheat condition exists. If the hi-limit sensor reads a temperature of 116 degrees or more or if the temperature sensor reads 110 degrees or more. The circulation pump will activate for a minimum of 6 minutes or until the temperature has dropped to 106 or less. Usually the OH message is caused by a dirty or soiled filter or obstruction of water flow through the heater. If this is the case you might see the OH msg followed by the FLO message alternating on your control panel. It can also be caused by a bad temperature sensor or bad hi-limit sensor. If the OH message is left uncorrected long enough the watchdog message will appear.