Plumbing question.

My overflows have the standard 1 inch and 3/4 inch bulkheads. I was at lowes picking up my shutoff valves and I wanted the kind that has the union. I noticed on that kind that the hole in the middle get cut by almost half vs a slip valve that the hole stays almost at 1 inch or 3/4. Does it matter? Would the flow be restricted that much?

 

My biggest concern would be that any restriction increases the chance of a blockage. Are you placing these on the drains by chance?

 

I build a DIY overflow with 1in pipe and ended up purchasing a 1in to 1in hose adapter, well this adapter downgrades to 3/4in. After testing over and over again I noticed the 1in to 3/4 was my bottleneck and needed to be removed.

Basically you want 1in all the way threw going to your sump.

 

Its a 300 Gallon Duel overflow. each will have its own shutoff. My problem is that even if you add a union it cuts the 1 inch to less than 3/4. Im looking for a good solution. Anyone have pictures of their dual overflow plumbing.

 

You really shouldn't have a valve on the drain side, the proper way to throttle flow is on the return side. It's a flood waiting to happen.

 

They are only their for tank maint. They will shut off the flow.

 

Yes, anywhere that the I.D. is reduced, it can restrict flow and allow a blockage to occur more easily. I'd recommend the standard slip-on valve, and then attach a union coupler with a short piece of PVC.

 

I see why, but if you turn off the return, then nothing can flow down the overflow (just like on a power outage, nothing being pumped, nothing being drained). You can save yourself the cash and the restriction. But if you're more comfortable with them there, I would use the slips so that there is the least restriction possible.