Plumbing in the Home/Backflow preventer


Hi Louie. Thanks for volunteering. I'm getting ready to replace my above-ground backflow preventer to my irrigation system and I have a two questions (hopefully easy ones):

1) The last step in the installation instructions says:
a. close #2 shut off valve
b. pressurize the device
c. bleed air through test cock #4 and then open #2 shut off valve

To pressurize and bleed, does this just mean turn on the water supply, slowly open test cock #4 and then reclose it before opening #2 shut off valve?

2. Do I need to use something like plumbers tape when connecting this Apollo RP4A 3/4" backflow device complete with shut off valves into my piping?


Going to bed so ill make this fast :)

1) once it's all hooked up, turn water on SLOWLY until it's pressurized (u stop hearing water flowing)

Then open up the side ports and let em blow like a whale,
Starting closest to the inlet side first for about 10 seconds each.

2) Yes. Any time that you make a male to female connection, you always have to use something. I do not use Teflon tape, I use Teflon paste. It can be had at Lowes or Home Depot or any hardware store. Just make sure it is white and has Teflon in it. Do not go for gray or any other color just white. If you want a super duper will never leak connection, wrap it a few times with Teflon tape then put paste around fitting and tape.

Have a good night  

Plumbing in the Home

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Louie The Plumber


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