I have a question for the seasoned landlords...

How do you handle it if a tenant calls you about an issue that they feel is an emergency (which may or may not be an actual emergency) and you are not able to go over there immediately. For example, their shower is not draining, or the stove will not turn on - and you are at work, or away visiting family in another state etc. 

Can you run into legal trouble if you tell them you will check on the issue in a day? What constitutes an actual legal "emergency" that you have to address immediately?