Shut Off Solenoid Problem

[freestone]

http://www.marinedepot.com/ps_ViewIt...s~vendor~.html
Last night I hooked up this float and shut off valve to my R/O unit. Not really sure how this thing is supposed to work. Once the float is raised and stops flow into holding tank, water continuous to come out of the waste end of the r/o unit. I assume this is to build up pressure. After about 7-8 minutes with the float in the off position, and pressure has built up, the solenoid starts making this really load rumbling noise for about a minute. Also, I can't seem to make the connection at the float valve tight enough...it keeps leaking...causing the solenoid to loose pressure and cycle open/closed.

Has anyone had this same problem or know of a way to fix it. Maybe someone could post a pic of their shut off to see if I have this thing hooked up properly.

Thanks,
Scot

[Playa-1]

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