Sensor (Laser Counter) Replacement

[PurpleAir]

Sometimes, the laser counters (or channels) in a PurpleAir device can fail for a number of reasons. This article is meant to guide you through purchasing and installing replacement laser counters for your device.

We always recommend reaching out to PurpleAir support at contact@purpleair.com to see if the issue you’re experiencing can be remedied before replacement.

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Replacement Laser Counters

The following sections outline the replacement process for each model of PurpleAir device. If PurpleAir has manually downgraded a channel in your device, you’ll need to contact us to remove the downgrade.

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PA-I Indoor

Laser counters for the PA-I Indoor sensor can be purchased here. Please ensure that “TOUCH and PA-I-Indoor Laser Counter” is selected in the dropdown box. The Indoor uses a Plantower PMS1003 laser counter.

A video detailing the replacement process can be found here: PA-I: PA-I-Indoor Laser Counter Replacement

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PurpleAir Classic/PA-II or PurpleAir Classic-SD/PA-II-SD

Laser counters for the Classic or Classic-SD can be purchased here. Please ensure that “PA-II / PA-II SD Laser Counters (Pair)” is selected in the dropdown box. The Classic uses two Plantower PMS5003 laser counters.

A video detailing the replacement process can be found here: PA-II-SD Laser Counter Replacement

The PA-II Classic laser counter replacement process is nearly identical to the PA-II Classic SD. Any sections that mention the SD logger or SD card can be dismissed, as the non-SD version does not utilize an SD card.

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PurpleAir Flex/PA-II Flex

Laser counters for the PurpleAir Flex/PA-II Flex can be purchased here. Please ensure that “FLEX and ZEN Laser Counters (Pair)” is selected in the dropdown box. The Flex uses two Plantower PMS6003 laser counters.

A video detailing the replacement process can be found here: PA-II-FLEX Laser Counter Replacement

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PurpleAir Zen/PA-II Zen

Laser counters for the PurpleAir Zen/PA-II Zen can be purchased here. Please ensure that “FLEX and ZEN Laser Counters (Pair)” is selected in the dropdown box. The Zen uses two Plantower PMS6003 laser counters.

A video detailing the replacement process can be found here: PA-II-Zen Laser Counter Replacement

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Learn More

Sensor Maintenance
PurpleAir Map Guide
The Confidence Score

[jkwong1218 (Jonathan K. Wong)]

Hi PurpleAir Team,

I just replaced the laser counter for our PA-I Air Quality Sensor. The sensor powered right up and is indicating a bright green quality reading, and it even shows on the air quality sensor map where our previous sensor showed.

But how is that possible? Our previous sensor had a device-ID of:

80:7D:3A:56:39:2F

I understood this MAC address to be unique to our previous hardware device

The new laser counter that now resides inside our previous housing came with no MAC device ID label and did not require a connection with our home WIFI network? So how did the new laser counter that I just installed acquire the MAC device ID of our previous sensor?

Here’s a photo of the back of the new laser counter (with no MAC device ID label), and the back of the previous laser counter (with the MAC device ID label.)

Thank you.

Jonathan.

[Kieran (Kieran Berryman)]

Hi @jkwong1218

A device’s MAC address, and its identity in the PurpleAir system, is tied to its mainboard, and not the laser counters. Laser counter replacement will not affect a sensor’s ability to report to the map.

It is important to note that the MAC on your old laser counter is still the MAC for you sensor, so you might want to keep it on hand somewhere.

On the flip side, if a sensor’s mainboard were to be replaced, that would affect its MAC and ability to report to the map. However, this wouldn’t happen, as we don’t replace mainboards and would instead replace with a new sensor.

[jkwong1218 (Jonathan K. Wong)]

Excellent response. Thank you!

[Richard_Perez]

I’d like to upgrade the PM sensor in the Classic with the new Flex/Zen sensor. Is it compatible with the Classic motherboard and housing of the Classic?