tenants responsibility

Other

I have a number of unfurnished properties let to tenants using generally the RLA lease and would be grateful if you could clear up the following questions over whether the landlord or tenant is responsible for certain repairs

1. The fitted oven requires a new heating element. If the tenants had provided their own cooker, presumably they would have been responsible for repairing it.
2. The gas fire in the lounge has stopped working. The tenant thinks a bird or bird’s nest may have fallen down the chimney. They are responsible for sweeping the chimneys but as this one has a gas fire fitted, it cannot be swept in the normal way.

If you deem the tenants responsible for these repairs could you suggest a clause which could be added to a lease which would shift responsibility to the tenant and would clarify the situation.