plumbing drain and return questions.

[LoJack]

Originally Posted by MinPhase

I wouldn't put a gate valve on the overflow simply because the flow is only controlled by the rate of return, if you restricted outflow from the display using a gate valve your tank would simply overflow. The only time you restrict flow is on the output side of a pump.

With both the Herbie and the Bean you put a valve to induce a full siphon, with a secondary drain handling the overflow. Much Much Much quieter than a durso, and much safer

[The Guy]

Originally Posted by MinPhase

I wouldn't put a gate valve on the overflow simply because the flow is only controlled by the rate of return, if you restricted outflow from the display using a gate valve your tank would simply overflow. The only time you restrict flow is on the output side of a pump.

A gate valve on the flooded 1" overflow refers to a "Herbie" super quiet and safe system and is done all the time, the second 1" is an emergency overflow that is located just slightly above the set water height in the tank to prevent a flood from happening. The size if the 2 pipes from the DT overflow to sump depends on the flow you require, I just used 1" as an example.