GMP231 is designed to be calibrated while it remains installed through an incubator wall. If you calibrate the GMP231 without it being installed, note the following:
- If you are using a calibration gas, prevent it from entering the electronics housing of the GMP231. Otherwise it diffuses through the probe to the sensor and alter the CO2 reading.
- Make sure that the PTFE filter is in place when performing calibration.
- If you are using the calibration adapter accessory to feed the calibration gas to the sensor, note that you must have the silicone plug and the PTFE filter installed on the probe. Without both of them in place, the calibration adapter does not function properly. Vaisala recommends replacing the silicone plug and the PTFE filter before calibration.