Posted: 9 months ago Quote
Today, I bought a new starter kit and partially set it up.  I am optimistic that this will work out.  However, before going further I wanted to make sure I wouldn't contaminate the water supply.  A question, then, about the backflow preventer:

First, set up.  I made the following connections:

Faucet -> Quick Connectors* -> Backflow Preventer -> 25 PSI regulator -> 1/2" drip tube -> Crimped at the end

I made a single punch into the 1/2" drip tube to connect a green landscape stake assembly through a 10 GPH flow controller (that is, the stakes that came with the kit).  The stake had a mister head attached.

*Quick connectors are very similar (but probably not exactly equal) to these:

Anyway, I wanted to know if the backflow preventer was working so, I turned my faucet on, left it on for a few seconds, until the pressure seemed stable in the system, and then shut faucet back off.  I quickly detached backflow preventer from the faucet (at the quick connectors, but leaving everything else connected downstream to the backflow preventer).  After a few seconds, a geyser of water erupted from the backflow preventer.  This seems contrary to what I would have expected.  I expected the pressure to slowly be released through the connected mister and the backflow preventer to prevent any backflow.

Does this indicate that the backflow preventer is not working?

Thanks for your help.