Replacing a Ball Valve on a Pressure Vacuum Breaker (PVB)

Replacing a Ball Valve on a Pressure Vacuum Breaker (PVB)

Sprinkler Repair & Service

Replacing a Ball Valve on a Pressure Vacuum Breaker (PVB)

Written by:
Jonathan Manning, CLT – Irrigation
A Better Garden Maintenance, LLC.
Denver, Colorado

Parts needed: -Ball Valve (look for a similar/exact part)
-Copper Pipe cutters
-Copper coupler w/o stop
-Sand paper/ mesh
-2 channel locks
-wet rag

You will need to cut the copper pipe under the ball valve (leaving enough room to fit the copper coupler) and remove it. If you are careful the pipe and the male adapter may be reused. If this is not possible then you will need a male adapter and some copper pipe as well. After the ball valve is removed, you will need to use teflon tape and wrap (clockwise – turning with the threads) the male sections on either side of the ball valve. Re-thread the ball valve onto the main assembly and then re-thread the male adapter into the ball valve.

As you finish re-threading the ball valve, you will need to sand down the outside on both sides of where you cut the pipe. You will also sand the inside of the coupling. After this is completed and the pipe is bright & shiny, generously cover the outside of the pipe and the inside of the coupler with flux. Slide the coupler partway down on one of the pieces of pipe. You will need most likely need to flex the pipe to allow it to fit properly. Have a wet rag handy (this will be used to quench and clean your joint). Ensure the pet cocks on the backflow casing and the drain cap (if you have one) are open to allow air to circulate. It is also necessary to make sure the water is completely drained as this will prevent you from having a good seal.

Begin heating the coupler with the torch. It is important to not just heat the pipe as the metal will not fuse with the solder if both pieces of metal are not hot. As the metal heats up it will glow red, on the opposite side of where you are heating touch the solder to the joint. It should immediately melt and be sucked down or up into the joint (This must be done on both side of the coupler!). You will be able to see a silver puddle all around the coupler. Next take the wet rag and quench the joint (this can also be used to clean up the pipe from having the lines of solder running down the pipe). Turn the water on and if no water sprays at you, the work is complete.

As a side note, using excessive solder there is a chance it can get into your main line or manifold and cause damage to your valves (stuck valves, holes in the diaphrams). After doing this project you should open up the drain in the valve box and attempt to flush out any excess solder.

Remember, all municipalities require companies to be licensed to perform any form of repair on a Backflow Prevention Device. This is important because these devices protect you, your family and your neighborhood.

01 Apr 2013 no comments

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