You can use a standard Windows 8 or 8.1 ISO to load an Acer device (some models only support 32 bit versions) but afterwards you have to load the special Acer drivers (can download from the support page) to make things like a touch screen or thermal management or WiFi work.
Luggable, 1983 My first PC
Please: Make a recovery drive and store a full system image offline before upgrading.
Our friend and comrade IronFly has reached his 10,000th post to our little Community. During the last 4 years he has helped countless Acer customers providing help, advice and answers. The Acer Community team feels honored to count you as our friend. Thanks IronFly!