Herbie style overflow

[Black Phantom]

Sounds like trapped air to me. How close to the top of your overflow is the valve. It might be that there isn't enough water building up in the pipe after startup to push the air out.

[Whatigot]

would airline fed into the pipe solve this issue?

[Nevin]

Can you just remove the downturned elbow? If it's there to make your normal drain lower than the emergency drain then it won't work. How about an elbow turned upward on your emergency drain to make it higher instead?

Regards,
Nevin

[sphelps]

Pictures are amazing things, got any??

[JDigital]

Herbie should just be 2 straight stand pipe.. the emergency being taller than the main drain.. the main drain should be full submerged under water.

(for some reason it didn't upload vertically.. but u get the idea...

[Chad]

Ok, i will get photos tomorrow.. I did not make it vertical through the bottom.. I did it through the side. I didn't read anything that had said I could only do it completely vertically. There are atleast 2 elbows in it.

[fkshiu]

Hmm, that's interesting. I've got a 90 and a 45 degree elbow on my Herbie main drain and it has never had any difficulty re-starting. A Herbie is completely gravity-based so it's hard to imagine a situation where one would not re-start as long as water was flowing downwards.

What sized pipe are you using? And how much flow do you have going through the overflow? Perhaps with narrow pipes and low flow the valve could be closed enough such that some slime or gunk creates a blockage???