Thermal Expansion Due to Hot Water Heater

When water is heated in a hot water heater, water expands and builds up pressure in the water pipes in your home. This is a result of the backflow preventer near your water meter preventing water from leaving your home and reentering the City’s water pipes. To remedy this issue, plumbers now install a thermal expansion unit in your home usually near the hot water heater.

Exterior Water Hoses Connected to the House

If you are using a water hose and say for example have it connected to a fertilizer or pesticide applicator, you will need a backflow preventer on the hose to prevent backflow from occurring from the applicator back into the house. This would apply to a pressure washer also.