Any clause would almost certainly be unfair and therefore void under the Unfair Terms in Consumer Contract Regulations on a standard six to twelve month AST - why not just remove the appliances, sell them and then reduce the rent? The tenant can buy their own if they wish.
I assume you know that there are some repairing obligations you cannot escape from under statute? This will include maintaining the heating, boiler plumbing, baths and showers.
The above represents my own opinion, derived from personal knowledge and should not be relied upon as definitive or accurate advice. It is offered free of charge and may contain errors or omissions or be an inaccurate opinion of the law. I accept no liability for any loss or damage suffered as a result of relying on the above.