Calibrate your ICO's pH and ORP probes

Why calibrate ICO sensors ?

Calibration of your ICO's probes is necessary to ensure the reliability of the measurements sent to your application. If it is not done regularly, the pH measurements and disinfection rate (ORP) will become inaccurate may drift over time which can lead to inappropriate use of products (over or under dosing) and alter your bathing experience in your pool.

The calibration of the probes is therefore essential to keep the water healthy.

Specific case with new sensor

If you replace a sensor with a new one, it is not necessary to calibrate it. However, you must regenerate your new probe with KCl liquid then reset the sensor in the application when it is installed. This procedure must be carried out as soon as your new sensor is installed, and before the next calibration. It allows your ICO to take account of the factory settings. For more information, please refer to the page how to replace an ICO probe.

When calibration is needed ?

When you receive a new ICO, the probes are already calibrated. So you can start the season with your probes without having to calibrate them. The first calibration of your sensors should be carried out within 6 months (if you use your pool or spa all year round) OR at the start of the next season (for seasonal use).

After six months' use of your ICO (or 1 season), calibration proceeds at the following rate:

Seasonal use (pool and spa) : calibrate your sensors once per year, at the beginning of the season
Year round use (pool and spa) : calibrate your sensors twice a year, every six months

Finally, calibration should always be carried out at the beginning of the season, not before wintering.

Before calibrating ICO

At the start of the season

Charge the ICO battery for 8 hours

After switching on ICO, access the sensors by unscrewing the bottom part of your device.

Probe regeneration: Soak the pH and ORP probes in the KCl solution for at least 1 hour, pouring the liquid over the sponges in the black caps. Rinse the probes with demineralised water.

Calibration: now go on to the probe calibration stage.

The necessary material

The ICO sensor calibration kit includes :

pH7 buffer solution

470 mV ORP buffer solution

a KCl regeneration solution

a base for calibration

pH4 buffer solution

Buy a calibration kit in the Ondilo shop.

Preliminary instructions:

Perform the calibration in a room at room temperature (recommended temperature is 25°C / 77°F).

Place your ICO next to your smartphone

If you want to perform a full calibration, start with the pH calibration and finish with the ORP calibration. The ORP solution is acidic. If you start with the ORP calibration, this will interfere with the pH calibration.

Rinse the probes and calibration support thoroughly between 2 solutions. Dry carefully with a soft cloth.

Important: We recommend that you keep the pH4 solution in another container until the calibration has been validated, , if you need to recalibrate.

Important: We recommend that you store the pH7 solution in another container until calibration has been validated. , if you need to recalibrate.

Watch this video:

How to calibrate the pH probe?

Calibrating the pH sensor is tricky because it requires 2 measurements, with a change of solution. When you have completed the 2 steps, ICO checks the consistency of the measurements and may give you an error message if they differ. In this case, ICO will ask you to repeat all the calibration steps.

When you are on the Remote Control page, click on the pH probe calibration icon.

Image of the application showing the step and button for calibrating the pH probe

Calibration starts with the pH4 solution

Step 1: Rinse and dry the probes

Rinse the probes thoroughly with clean water and dry them carefully with a soft cloth.

Reset ICO

Step 2: Pour the pH4 solution into the holder.

Place ICO on the cradle and start the calibration

Step 3: Measurement in the pH 4 solution

Calibration takes about a minute, so make sure you keep your phone close to ICO.

Step 4: pH4 measurement complete

Click on continue

Important: We recommend that you keep the pH4 solution in another container until the calibration has been validated, , if you need to recalibrate.

Step 5: Rinse and dry the probes

Rinse the probes thoroughly with clean water and dry them carefully with a soft cloth.

Step 6: Pour the pH7 solution into the holder.

Pour the pH7 solution into the base and continue the calibration procedure

Step 7: Measurement in pH7 solution

Calibration takes about a minute, so make sure you keep your phone close to ICO.

Step 8: pH7 measurement complete

Then click on Save

Important: We recommend that you store the pH7 solution in another container until calibration has been validated. , if you need to recalibrate.

Possible error messages related to pH sensor calibration

In some cases, your ICO device may tell you that the calibration of your probe has not worked.

Message The measurement seems incorrect

Here are the cases that may explain this message:

Image of the application showing the stage at which the ‘measurement appears incorrect’ message appears

ICO probes are not sufficiently hydrated, which is why it is important to leave ICO and the probes in water for at least 24 hours before calibration.

Calibration conditions are not good: the calibration base must be washed and dried, the probes rinsed with tap water and dried.

ICO was not restarted prior to calibration

Calibration failed message

pH calibration failure on the ICO application

This ‘Calibration failed’ message appears when the difference between the two measurements is too small or too large. This means that the difference between the measurement taken in pH4 liquid and that taken in pH7 liquid is too far from the tolerated difference.

Be sure to follow the procedure described in the calibration tutorial. Careful rinsing and drying of the probes and calibration stand between each step is essential to avoid falsifying the measurements.

ORP calibration

Calibration of the ORP probe

Step 1: Rinse and dry

Before calibrating the ORP probe, rinse the probes thoroughly in clean water, then wipe them dry with a soft cloth. Do the same with the solution base

Step 2: Pour the ORP 470 mV solution into the holder.

Place ICO in the base and continue with the pH4 measurement.

Step 3: ORP probe measurement

The calibration of the ORP probe is in progress. Please ensure that your phone remains close to ICO at all times.

Step 4: Measurement complete

Save the results, ICO is calibrated!

Rinse the probes again and dry them, then replace the probe cover.

ORP probe calibration error message

Screenshot of the ICO application, with the message ‘incorrect measurement’

Make sure ICO has been in water for at least 24 hours before calibration

Make sure the probes and the calibration vessel are clean

Turn on ICO before calibration

If the measurement is not taken, restart ICO before trying again

If, despite these recommendations, the calibration has still not worked, contact our support department.