How to replace a vacuum breaker on a toilet

If you are like me you have used industrial/commercial type toilets hundreds or thousands of times without giving a second thought about how they work. I have now had some experience working on them, and while  I am still no expert, I do have the knowledge to work on them.

Vacuum breakers in industrial/commercial type flush valves are what seem to wear out the most in my experience. Some signs of a warn out vacuum breaker are:

• Water leaking from the top of the pipe where it joins the bottom of the flush valve
• Flushes taking too long or not stopping.
• Having to hold the handle down for the flush to complete.
• Unusually loud flushes.

The first thing to do is to shut off water. remove the cap.

Use a flat head screw driver to turn the water off. Turn clockwise.

Loosen the union. Use an adjustable wrench instead of this kind.

Or you can use a clothe to keep from scratching the fixture.

Unscrew the lower union. and remove the flush assembly.

Here are the three pieces of the new vacuum breaker.

Vacuum breaker shown installed. Makre sure to clean the pipe before putting the vacuum breaker in place.

Replace the flush valve and tighten the unions, making sure they are nice and tight. If they are not tight or the pipe is dirty that could cause the pipe to leak, or the toilet to keep flushing. After the joints are tight turn the water back on and check for leaks. I put some teflon tape on this one, because it would not stop leaking without it.