First, you should always look into the credentials of anyone you are hiring to work on your hot water heater. It is smart to hire the same contractor who installed the hot water heater to come and fix it. However, this is not always possible. In these cases, it is smart to make sure your contractor is properly credentialed. These credentials vary significantly from state to state. You should check with your local government offices to see if they have a list of necessary licenses that HVAC contractors are expected to have.

Get an estimate for the job before you hire a contractor. Some contractors will automatically try to talk you into buying a new hot water heater. This is often unnecessary and it's used as a ploy to talk you into spending more money on your repair work. You should get an estimate from anyone that you hire as a contractor to do work for you. This way, you will have a place to bargain from if the repair job starts to cost more than you thought it would.

Find a contractor that has a lot of insurance. Hot water heater repair work is often fairly straightforward and simple. However, the sheer volume of water inside of a hot water heater is problematic. It creates a situation where significant amounts of water can taint important parts of your life. In situations like this, it's important to find a contractor with insurance so you are protected from any financial problems incurred by worker error.