You can use the following options:
* App. (This is commonly used in lists or catalogs)
* Appl. (This is less common but still understandable)
* Appls. (This is another option but may be less clear)
However, it's generally best to avoid abbreviations unless you are writing for a specific audience that would understand the abbreviation.
In most cases, it's clearer and more professional to use the full word "appliances".