Does the sensor in Dyson Air Purifiers have any issues?

The below article talks about issues that the Dyson sensor may face occasionally, how to fix this issue, along with some frequently asked questions about Dyson purifiers, their functions, and improving indoor air quality. 

Does the sensor in Dyson Air Purifiers have any issues?

While it is uncommon, a number of customers have reported of an issue they face in regards to malfunctioning of the sensors in Dyson air purifiers. Namely, the sensor may show particulate matter readings for PM2.5 and PM10 as 999, when that may not be the case. The below article talks on addressing this error and getting your purifier working as effectively and efficiently as possible. 

The Problem 

The problem that the dyson sensor faces is that it may display particulate matter concentrations as 999, when that may not be the case. According to experts at Dyson, this issue occurs when the sensor or the circular amp is blocked, usually by dust, causing the malfunctioning or sensor failure. The issue can be resolved by just cleaning the sensor of the purifier. 

Fixing the sensor malfunction

Below are the steps you need to follow, if your sensor shows the same error.

Step 1: Locate the sensor in your Dyson air purifier. Typically, they are to the left of the display on the purifier. The holes you would notice, are most likely the sensor holes which may be blocked by dust. Other models may have these sensor holes in different parts of the purifier, therefore, make sure to locate the sensors in accordance to the model you may have. 

Step 2: Once you locate the sensor holes. Turn off your appliance. 

Step 3: Clean the sensor using one of the following methods-

Step 3.1.: Use a dry dusting brush to brush dust from the sensors, and push it into the holes gently to remove dust from the sensor paths. 

Step 3.2.: Use a lightly powered vacuum cleaner with an appropriate attachment to vacuum the dust and debris articles on the surface of the sensor or the sensor pathway. Using a HEPA filter attached vacuum cleaner would ensure that any dust or debris captured is not re-introduced into the sensor when you would vacuum it. 

Here is a YouTube video that demonstrates a user cleaning the sensors using a vacuum cleaner. 

Step 3.3.: Using compressed air to blow out any dust and debris from the sensor. A blow drier on cool setting or a can of compressed air should do the trick. 

Step 4: Plug your appliance back, and let it reset. If the dust and debris have been cleaned properly, the particulate matter readings should now correspond to the actual values in your room. 

If the matter persists, even after thorough cleaning of the sensor, you may be required to clean the filter. Remove the filter from the appliance when its powered off, vacuum the filter to remove dust and debris, and then reinstall it into the appliance, and power it on. On rare occasions, the purifier might require a hard reset along with the cleaning of the sensor paths. It can be done by following the below steps:

  • Power down the appliance, and remove the power cord
  • Re-insert the power cord while simultaneously pressing down on the power button of the appliance 
  • Once the display screen starts to flash, let go of the power button and allow for your purifier to acclimate to the surroundings. 

Frequently Asked Questions (FAQs): How do I fix the 999 reading on my Dyson air purifier?

Does cleaning the dust off the sensor and the sensor pathway fix the 999 reading for all Dyson air purifiers? 

This solution usually works for most Dyson air purifier models including Dyson Pure Cool Tower TP04 & DP04, Dyson DP05, Dyson Pure Cool tower, etc. (Colman C., n.d.)  

How to compare the benefits of different Dyson air purifiers?

The article available through this link compares 12 top selling models of Dyson air purifiers. 

Do Dyson air purifiers use true HEPA filters? Why is this good and is it worth it?

Yes, all Dyson air purifiers use the true HEPA filters which is capable of capturing up to 99.99% of airborne pollutants and contaminants. Dyson air purifiers have been known to work efficiently and effectively due to its technological innovative enforcements and design efficiencies, due to which it is one of the most preferred brands across users in the world for improving indoor air quality levels. 

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Chuck. (2020, April 05). Dyson TP04 cleaning sensor resolves 999 status for PM 2.5 & 10. YouTube. Viewed on 01-23-2022. 

Colman C. (n.d.). Dyson air quality sensor problem? Try this quick fix. Machinelounge. Viewed on 01-23-2022.,sensor%20(and%20the%20amp)

Eddies P. (2020, December 30). Dyson Fan PM10 / PM2.5 Severe 999 Fixed. Geeks Hangout. Viewed on 01-23-2022. 

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