does it need?

[Nsr250NYC]

does the internal overflow return need a hole to be drilled in? i know the return for a hangon back overflow require a hole drilled but what about internal?

 

[zahner]

you mean a siphon break, right? I would drill one

 

[MPISCIOTTI]

no it does not need

 

[FRY]

no when the water goes below the 90 elbo it will stop siphon

 

[zahner]

i think he meant in the return line, not the durso. without a siphon break in the return, you would still have back siphon from the return into the sump until the water level in the tank drops below the level of the output, no?

 

[jhale]

I think he means the return as well, so yes you need a siphon break hole.

 

[Kedd]

John is correct, unlesss your sump can handle all the water down to the return outlet.


Kedd

 

[Nsr250NYC]

thanks guys, so it's better to be safe than sorry. so how big the hole and where? meaning how low below the waterline. thanks