Your water heater allows you to have hot water whenever the need arises. If you have dishes to do, you need hot water. If you need to shower, you have hot water. If you need to do laundry, you have hot water to allow you to do this as well. Without a hot water heater, it's back to boiling hot water for these things - who has the time to do that?
If you have commercial refrigeration units in your place of business, such as if you run a bar or restaurant, you will need to know when to call a commercial refrigeration repair service. After all, even if you have a good-quality refrigeration unit in place and even if you take good care of it, there is a chance that problems will arise. These are some of the times when you will probably want to call a commercial refrigeration repair service to come and help you out.