You say it's new but in “generally excellent condition”?
An owner is responsible for just about the same items whether they live in it or not. In general, if you had to repair or maintain if you lived there, you have to when you don't! People pay top dollar for rents these days. They have every right to expect everything in working order and for repairs to be carried out.
I agree with CBF's comments above. If you have a tenant that finds a problem and promptly relays it, you have a tenant who cares about his/her home and therefore cares about yours. Much better to have someone in your place that points out any problems than one who moves out without letting you know, when the problems have become much bigger over time and therefore more expensive.
You should attend to anything electrical as soon as possible. And since you are new to “landlording”, I hope you have landlord insurance.