Everything Vacuum Breaker

Although we have been enjoying relatively cool weather for this time of year a lot of people find it is about time to turn the irrigation system back on for the summer. One important part of the irrigation system is the vacuum breaker, installed above ground and typically in front of the house.

What is a vacuum breaker?

A vacuum breaker is essentially a backflow prevention device. It prevents water from flowing backwards and potentially contaminating the domestic water in your house and the public water system.

How might backflow occur?

Backflow is caused by cross-connections that have the potential of allowing contaminants into the drinking water system.

There are two possible scenarios:

1. A drop in water pressure on the fresh water side – also known as back siphonage: When the water pressure in the municipal system abruptly drops, e.g. the fire department uses water from a nearby water hydrant, the imbalance in pressure pulls the water the other direction.
2. A rise in pressure from the waste water side – also known as back pressure: Back pressure occurs when there is higher water pressure e.g. in a fire protection system or in a multi-story building which could force contaminated water into the public water system.

How does the vacuum breaker work?

Inside the vacuum breaker is a check valve that is pushed open to let water flow in the correct direction. When the water is turned off the valve closes. The closed valve keeps water from going the opposite direction into the house. The vacuum breaker also contains an air vent (the brass bell shaped part on top) that is vented to the atmosphere (open-air) and that ensures the proper functioning of the valve and prevents spillage at the device.

Does it require maintenance?

The maintenance for a vacuum breaker is minimal. But there are a couple of things to be aware of: When turning the vacuum breaker on for the season check for any possible leaks on or around the device. Also, make sure to drain all the water from the vacuum breaker before the first freeze in the winter – otherwise you might discover a split pipe and look at a costly repair when it is time to turn it back on in the summer.

Anything else?

There’s a lot more information out there on the devices themselves and the different types that exist. This is just an overview that is meant to be kept simple and to get you a little bit more familiarized with the kind of bizarre and funny looking device made out of pipes and valves sitting in your front yard. We at Green Plumbing Solutions are happy to assist you with any more questions you might have as well as with the repair or replacement of your vacuum breaker once a problem occurs.