A lack of hot water can be caused by a variety of issues. In electric water heaters, a power loss or heating element failure can cause water to no longer heat in the tank. In gas water heaters, a faulty gas connection, a bad pilot light, or a bad burner can cause no water to heat.

Press and hold down the water heater pilot button. Keep the pilot button pressed down so that you'll be able to start up the water heater. If your model doesn't have a specific pilot button, press and hold the On/Off control.

Some of the most common causes of hot water issues include gas leaks, water tank leaks, gas valve failures, pilot light problems, electric heater malfunctions, thermostat issues, faulty heating elements, an undersized tank, and even the weather conditions.

It all depends on the type of water heater you're using. Here are some common heat up times for different water heaters, assuming the appliances are new and properly sized for the home: Electric storage tank water heater: 60–80 minutes. Propane storage tank water heater: 30–40 minutes.