Very few older houses that I inspect have anti-siphon devices or vacuum breakers installed on any of the exterior hose bibs. Anti-siphon devices are a simple, yet important gadget that you can pick up at your local hardware or plumbing store for $2 to $3.
The picture above shows a anti-siphon device for a hose bib.
Anti-siphon devices have been proven effective to prevent contamination of your potable water supply. For example, let’s say its a hot summer day, and your kids are in the back yard playing in an inflatable swimming pool – water hose running in the pool. A problem with the city’s water supply causes a loss of water pressure to your neighborhood. Without an anti-siphon device, it is possible for the pressure drop to cause water to be siphoned from the kid’s swimming pool back up through the hose, hose spigot, and into your water supply and distribution piping. A properly functioning anti-siphon device will effectively prevent this from happening.
The diagram above illustrates how back-siphoning can occur.
These anti-siphon devices are essentially one-way valves designed to stop the flow of potentially contaminated water back into the drinkable (potable) water supply. Installation is simple, and requires only screwing the piece on to the hose bib like you would connect your water hose. Your water hose can then connect to the male end of the anti-siphon device. Some anti-siphon devices have a setscrew that you can tighten, which prevents the device from accidentally loosening when you are disconnecting the water hose.
The picture above shows how to install an anti-siphon device.
Missing anti-siphon devices is one of the more common deficiencies that we find here at Blue Star Real Estate Inspection Services. When you choose us to perform your home inspection, you can trust that when we are done, you will be thoroughly informed about the condition of the house you plan to buy. Call Blue Star Inspections today to schedule your home inspection. 361-462-9018.