Is the inside plastic?
Yes, it has a hard plastic liner inside to hold the water. And it's BPA free.
How long does this run?
That depends on your setting. Reference working time: 5-7 hrs continuous mode, 7-9 hrs intermittent mode.
Can I just use the machine with only water? No essential oils or anything.
Sure you could, you could use it as a humidifier without oils.
Can I use boiling water? What water temperature range allows it to work best?
Absolutely not. You just use room temp water.The tap water is ok, and we recommend to use with distilled water to prolong its working life.
Can I use it in my car?
"It's a bit big for a car and you would have to have an adapter as it has a plug for a typical home outlet. For the car, I would recommend InnoGear USB Diffuser.
https://www.innogear.net/products/50ml-usb-car-essential-oil-diffuser"
Is it noisy?
Not completely quiet but very unnoticeable.
What are the warranty details?
All our products have 12 months warranty, and if you register your products you will receive an extra 6 months warranty(this gives you a total of 18 months of warranty.)
Register Link: https://www.innogear.net/warranty