How a Boiler Backflow Preventer Works

A boiler backflow preventer is designed to prevent the cross contamination of drinking water from boiler discharge and other contaminating water. The backflow preventer is required by many communities as a required piece of equipment that is attached to the boilers. Information concerning how the backflow preventer works seems to be limited although part information can be found through various sources online. Determining how a backflow preventer works is important if you are determining the necessity of having this device attached to your boiler.

If your community requires the use of a backflow preventer for your boiler, this can be installed by a mechanical contractor to an existing system. If you are installing a replacement boiler or if this is part of a new construction, the backflow preventer will already be included on newer systems.

What a Backflow Preventer Does

A backflow preventer is a device to prevent backflow. It does this through an air gap used to eliminate a cross-connection or provides a barrier to the backflow. There are 3 types of mechanical backflow preventers: the reduced-pressure principle assembly, the pressure vacuum breaker assembly and the double check valve assembly. There is also a secondary type of mechanical backflow preventer, which is the residential dual check valve.

Costs for a Backflow Preventer

The mechanism, if purchased separately, costs between $15 to $30 depending on the retailer. You may add another $50 to $100 in installation costs to have someone come to your home and weld the backflow preventer to the boiler to enable it as part of the system. The part has a manual valve that can be engaged to prevent a backflow, but it works on a siphoning process through the air gap that prevents the back up and cross contamination of water running through your plumbing system.

Obtaining Additional Information from a Plumber

A plumber or boiler expert can provide more detailed information on the use of a backflow preventer and the requirements for the community in which you live in on whether or not it is important for you to include this mechanism on your boiler. Again, as most communities are making the use of a backflow preventer a required part, more than likely you will need to make the investment in purchasing a backflow preventer for your boiler as well as pay the appropriate installer to make sure that it is working properly.

Checking Local Standards

Check with the building inspector or other professional located in your community to ask questions about the installation of and requirement for a backflow preventer in your home. They can also let you know who is certified to perform this work and who can best help you meet the requirements for a backflow preventer on your boiler. If you have concerns about the contamination of water and the introduction of certain contaminates in your water supply, your decision to have a backflow preventer installed has already been made.