Failing A2L Sensors
Last updated: Aug 27, 2026
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Tech support has been noticing a high volume of replacement A2L sensors, and we are investigating. In our opinion, this failure is pre-mature, being that we have been working with A2L for only 2yrs now. Some failures are relatively soon after install, some do make it a full season. We have reached out to the OEM's (equipment manufactures) and expressed our concern and thoughts. I have been told they are looking into it since I first brought the examples to their attention.
Even though the sensor is rated for "some" moisture exposure (per IP54), we (JSWMI Tech Support) feel the sensor is being contaminated by condensate from the evaporator coil.
Our advice is this: If possible, during install, and during the process of finding the sensor cable, inspect the sensor location. I have seen refrigerant distributor tubes running in front of and above the face of the sensor. Do the best you can to get a picture of this and send into [email protected] along with the serial number of the evaporator. Then, try to manipulate the distributor tubing away from the sensor to help prevent moisture contamination. Also verify blower speed and TESP (total external static pressure). If the air velocity is high, that, can play a significant roll with condensate being blown into the sensor causing failure.
Below are pictures of examples we have seen.
