Your backflow prevention device guards your drinking water against contaminants. Cold weather can cause problems for this critical system unless you take steps to winterize your backflow preventer device. We will tell you the most important things to do to protect your family’s clean water.

Contamination risks

Contaminants like lawn fertilizer, industrial chemicals, common household cleaners, animal waste, and sewage are normally kept out of pipes that carry drinking, or potable, water. If a drop in pressure occurs in the pipes that carry non-potable water, these contaminants can be pulled into potable water pipes. Homes that have lawn irrigation systems, boiler heaters, inground pools, dishwashers or washing machines are all at risk for backflow contamination.

Types of backflow prevention assemblies

A backflow prevention device works by simply resisting the pressure of an impure fluid. Missouri only allows three types of backflow device assemblies:

  • Double-Check (DC)
  • Air-gap assemblies
  • Reduced Pressure Zone (RPZ) assemblies

In a high-pressure configuration, such as in a commercial building, the backflow device will either be a DC or an RPZ assembly.

Regardless of the type, if water freezes inside the backflow device, it can rupture pipes, causing extensive damage. Even if the pipes simply get bent out of alignment, the device will no longer function properly. This will require replacing the entire device at a significant cost.

If your backflow device is either DC or RPZ, you will not be able to drain water from the system without causing damage. Winterizing it will generally be done by clearing the relief valve so that the water can drain periodically and insulating the pipes to keep them from freezing.

A few minutes now, or a big pain later

Winterizing your backflow prevention device is quick, simple and inexpensive. We recommend inspecting and preparing your device for winter. If you are not comfortable doing this, you should have a licensed professional winterize it so that all the water is removed. We would love to not only winterize, but also test your backflow system. After all, backflow testing is mandated by the EPA and can only be performed by certified professionals like us.

We’ve been keeping pipes flowing in the greater St. Louis area for 60 years, regardless of the season. Keep your water clean and fresh by contacting us today.


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