When a Jandy AquaPure salt system finds a problem, it turns on its SERVICE light, shows a three-digit code on the display and beeps. The number tells you whether it's the salt, the cell, the flow sensor or the electronics. Here's what each code means and what to check first, from Jandy's own AquaPure and PureLink manuals.
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A Jandy AquaPure service code is a three-digit number the salt chlorinator shows with its SERVICE light when it detects a problem that needs attention, anywhere from low salt to a DC cord that isn't connected. Jandy, a Fluidra brand, says the codes are displayed twice a minute with an audible alarm.
The beep sounds once an hour, and only for the first service code. Holding the SALINITY button for 5 seconds silences it for 24 hours or until the power is turned off and back on, whichever comes first, and it returns if a new problem is detected. Silencing it doesn't fix anything, so note the code first. The other lights on the display matter too:
| Indicator | What it means |
|---|---|
| CELL ON | The cell is on. It stays off when production is set to 00%, during a rest period, with No Flow, for two minutes before the automatic cleaning cycle, in the low-temperature cutoff, or with a service problem such as salt below 2.0 gpl or too high |
| CELL RESTING | Normal when production is set below 100%: the cell rests part of the time |
| FLOW / NO FLOW | Whether the sensor detects water moving past it. With NO FLOW, the cell is turned off |
| CELL REVERSING | The automatic cleaning cycle. Chlorine production carries on |
| ADD SALT | The sensor reads the salt as too low. Jandy's target is 3.0 to 3.5 gpl |
| SERVICE | A problem needs attention, shown with a three-digit code |
Salt is shown in grams per liter: 3.0 gpl is 3,000 ppm.
| Code | What Jandy says it means | What to do |
|---|---|---|
| 120 | Low current in the forward direction to the cell | Clean the cell if necessary; check the DC cord |
| 121 | Low current in the reverse direction to the cell | Clean the cell if necessary; check the DC cord |
| 123 | Extremely low current to the cell | Clean or replace the cell if necessary; check the DC cord |
| 124 | Higher than normal current to the cell | Contact a pool professional |
| 125 | Cell needs to be cleaned | Clean the cell if necessary |
| 126 / 127 | Low current (forward / reverse) and input voltage below 100/200 VAC | Contact a pool professional |
| 144 | Low salinity, below 2.0 gpl | Add salt to reach 3.0 gpl |
| 145 | High salinity, above 4.0 gpl | Backwash if you have a D.E. filter; partially drain and refill until it reads 3.0 to 3.5 gpl |
| 170 | Possible front board service condition, or the unit isn't wired correctly | Contact a pool professional |
| 171 | Possible backboard service condition | Contact a pool professional |
| 172 | Flow sensor service condition, or the flow sensor is unplugged | Contact a pool professional |
| 173 | Low input voltage and the onboard power supply isn't regulated, or the unit isn't wired correctly | Contact a pool professional |
| 174 | Pool too hot for the AquaPure: the sensor reads above 108°F | Reduce the water temperature |
| 175 | Flow sensor air lock, or very low salinity | Check the sensor is installed as the manual shows; check the salt |
Jandy says to turn off power to the unit before attempting any service or repair. The codes it sends straight to a professional cover abnormal cell current, the supply voltage, the circuit boards, the wiring and the flow sensor.
The newer PureLink manual adds Level 2 service codes, 180 to 194, and says to contact your local pool professional if you see one. Each shows up on the display as one of the codes above, so the detail mostly helps the technician:
| Level 2 code | What Jandy says | Shows as |
|---|---|---|
| 180 | Heated sensor element not heating | 172 |
| 181 | Flow sensor temperature sensor failure | 172 |
| 182 | Salinity sensor sees less than 0.2 gpl: no salt in the pool, or the sensor is air locked | 175 |
| 183–186 | Flow/salinity sensor temperature probe errors | 172 |
| 187 | Front board power supply too low or too high | 173 if 188 is also present, otherwise 170 |
| 188 | Input voltage too low | 173 if 187 is also present |
| 189 / 190 | Relay not conducting in the forward / reverse direction | 171 |
| 191 / 192 | High cell current with cell voltage below 19V | 170 / 171 |
| 193 | Significant cell current measured while the SCRs were off | 170 |
| 194 | Cell current 85% lower than desired with cell voltage above 19V. The manual also lists a second 194: salinity reading invalid because of a front board error | 125 (cell dirty or needs replacement); the second one shows as 170 |
The letter codes are mostly status messages, not faults:
| Letter code | What it means |
|---|---|
| Lo | Low-temperature cutoff: chlorine production has stopped because the water is cold. The PureLink code table puts it below 54°F, and its winter section says production isn't permitted below 51°F; the older AquaPure 700 and 1400 manual says below 50°F |
| HH | A reading above the maximum range. For salt, that's above 4.5 to 6.5 gpl, depending on the water temperature |
| EC | An ORP unit or other external controller has shut off chlorine production |
| bo | Boost: 100% production for 24 hours of run time |
| JA | A Jandy AquaLink RS is controlling the AquaPure |
| Jb | The AquaLink RS is controlling it and Boost is on |
When an AquaLink is in control, production and Boost are set from the AquaLink's menus, and the AquaPure still shows salinity, temperature and service codes as normal. If the AquaLink itself acts up after a power cut, see our guide to restarting pool equipment after an outage.
Codes 120, 121, 123 and 125 point at the cell. The AquaPure cleans its own plates by reversing the current every 3 hours, and keeps making chlorine while it does, but in hard water scale still builds up between the plates. Our guide to what Houston's hard water does to pool equipment explains why it's so common here.
Jandy recommends checking the cell monthly for the first few months after it's installed, every two months if it tends to scale, and at least twice a year even when it stays clean. If the code comes back after a proper cleaning, Jandy's answer is a professional. A 123 can mean the cell is worn out: a replacement Jandy AquaPure cell is $2,000 to $2,600 installed with us, and our guide to salt cell replacement cost explains when a cleaning is still the better spend. A 124 is the opposite problem, more current than normal, and Jandy sends it straight to a professional.
Jandy's target is 3.0 to 3.5 gpl. Below 2.0 gpl the AquaPure shows code 144 and turns the cell off until the salt comes back up, because running on low salt damages the cell. Above 4.0 gpl it shows 145, and Jandy's fix is dilution: partially drain and refill with fresh water, backwashing first if you have a D.E. filter.
The reading comes from the flow/temp/salinity sensor, so a low number isn't always low salt. Jandy lists dirty sensor contacts or a faulty sensor as a cause, and says to confirm the level with a meter calibrated for salt (NaCl) or a titration test, warning that salt test strips can vary by 400 to 800 ppm. The sensor wants cleaning about once a year: a mildly abrasive green household pad until the contacts are clean and bright, a rinse, then power off and back on so it recalibrates. Our guide to a low salt warning when the salt is fine covers the same trap on other brands.
Real salt loss happens too: Jandy lists heavy rainfall and leaks, which is worth remembering after a big Houston storm. When you add salt, Jandy asks for salt that's at least 99.8% pure sodium chloride, with no rock salt and never calcium chloride. Brush it around, let it circulate for 24 hours, and check the reading again before you set the production rate.
The AquaPure is wired so the cell only runs when the pump is on, and the flow sensor is a backup that switches the cell off when it doesn't sense water moving. When NO FLOW stays on, Jandy's checklist is the pump (lost prime or clogged strainer baskets), closed valves, a dirty filter, something lodged in the cell, a sensor that isn't plugged in or isn't installed the way the manual shows, and sensor elements covered with PVC glue, tape or debris.
Flow rate matters as well. Jandy's AquaPure 700 and 1400 manual sets a minimum flow rate of 20 gpm, so a variable-speed pump turned down to a slow schedule can fall short even though it's running. Our guide to a salt system showing No Flow with the pump running walks through that.
Code 172 is a flow sensor service condition or an unplugged sensor, and 175 is a sensor air lock or very low salt at the sensor. If the sensor has been unplugged, plug it back in and cycle the power; Jandy says it needs that reset any time it's been unplugged. Beyond that, a 172 is a technician job, and the Level 2 codes that show up as 172 are all sensor faults.
Lo means the water is too cold and the AquaPure has stopped making chlorine on purpose; it isn't a fault. Very little chlorine is needed in cold water, and Jandy says running the chlorinator in cold water can over-chlorinate the pool. Boost overrides the cutoff for 24 hours if you need more, and if the pump runs through the winter on a freeze controller, Jandy says to turn production down to 10 to 20%. Our guide to salt cells in cold weather compares the cutoff across brands.
Freezing water can badly damage the cell and the sensor. Jandy's options are to run the pump continuously or to winterize; in Houston that means having freeze protection set before the first hard freeze, so see our guide to freeze protection settings.
Call when a code keeps coming back after the checks above, and for any code Jandy sends to a professional: 124, 126, 127, 170 to 173 and every Level 2 code. Jandy's manual says the AquaPure must be installed and serviced by a professional pool technician. A cleaning is $75 to $95, a replacement AquaPure cell is $2,000 to $2,600 installed, and a full new system, control unit and cell, is about $2,000 to $3,000, so when the board is also in doubt it's worth pricing both.
For everything else, see salt system repair. If you have a Pentair or Hayward system instead, see our guides to the IntelliChlor lights and the AquaRite Inspect Cell light.
Low current in the forward direction to the cell. Jandy's fix is to clean the cell if it needs it and check the DC cord, including its contacts at the cell. Code 121 is the same in the reverse direction, and 123 is extremely low current, where the cell may need replacing.
The cell needs cleaning: scale between the plates cuts the current. Jandy starts with a garden hose and only then a short acid wash. On the PureLink, Level 2 code 194 (cell current 85% lower than desired) also shows up as a 125, meaning the cell is dirty or needs replacing.
144 is low salinity, below 2.0 gpl, and the cell turns itself off until the salt comes back up. Before adding salt, confirm the level with a salt meter or titration test, because a dirty or faulty salinity sensor can read low. Jandy's target is 3.0 to 3.5 gpl.
The water is too cold and chlorine production has stopped on purpose. The PureLink code table puts it below 54°F and its winter section says below 51°F; the older AquaPure 700 and 1400 manual says below 50°F. Boost overrides it for 24 hours.
Hold the SALINITY button for 5 seconds to silence the beep for 24 hours or until the power is cycled. The code is there because of a condition, so fix the cause. If the flow/temp/salinity sensor has been unplugged, turn the power off and back on so it recalibrates.
A Jandy AquaLink RS automation system is controlling the chlorinator, so set production and Boost from the AquaLink's menus. Jb means the AquaLink is in control and Boost is on.
Tell us the code and what the salt reading says. If it's a dirty cell or low salt, we'll tell you so; if it's the sensor, the board or the cell itself, we'll come out and fix it. Licensed, insured, serving Cypress and Greater Houston.