A:Answer Hi there Meem, this is Tia from Dyson. To prevent damage to the unit, please do not use essential oils or any solution other than water in the water tank for Dyson PH01, PH02, PH03, PH04 & AM10. As well, you will never want to use air fresheners or any other chemical on filters or evaporator.
Thanks for your support of Dyson technology!
Best wishes,
Tia
Dyson Customer Support