Very slow draining of brand new POP-UP DRAIN

[foreverDIYgirl]

Just installed a brand new bathroom vanity with sink (overflow at front edge), faucet and metal pop-up drain (upgraded from the plastic pop-up that came with faucet due to 2 lousy gaskets) which is otherwise very similar to the factory pop-up. The metal pop-up has 5 good gaskets so no leaks after teflon taping the drain threads (yay!). Faucet water drains well except for when you run it on high and engage the pop-up so that water fills the sink 1/3 or more of the way up. I cannot figure out why the pop-up drain drains so slowly for larger sinkfulls of water ... and if that can be rectified. Not a huge deal for me but if I get a boyfriend, he may want to shave in that sink.

I read that surface tension builds up in these pop-drains because of the smaller grids under the pop-up where the water flows through. Fyi, pop-up is aligned perfectly with overflow cutouts at 12 o'clock & 6 o'clock. Definitely no clogs in the line through to the waste line. Any ideas on how to get pop-up to drain at normal rate even after puposefully filling the sink? Thank you in advance for your expertise.

 

[TomFOhio]

Is the pop up itself coming up high enough. Did you fasten it in with the rod. I usually just drop the popup in so it can be cleaned
out. If it comes up high enough take your p-trap off and see how well it drains into a bucket. If it drains good you probably have a
plug in the line.

 

[CT-18]

Is it a traditional pop up with a lever to stop up the sink. It may not be going up high enough to let the water drain. Does the drain have a vent on it, may not be getting enough air to drain properly.

 

[foreverDIYgirl]

Thank you TomFOhio & CT-18. I neglected to say that the pop-up is a new one that has no lever/bar (under the sink to the faucet) so it is fully self-contained within the drain line.. The pop-up is actuated by toggling it down (closed) and up (open) with no option to raise/lower the level of the pop-up.
1 - When the pop-up is open, water drains well and fast into the drain which I think means the drain line through to the waste outlet is clear.
2 - When I engage the pop-up and let a small amount of water fill the sink, disengaging the pop-up makes the water drain fast (normal rate). However, when I fill the water level ~1/3 of the sink full, that water drains SLOWLY (1' 15" for the sink to empty) once I disengage the pop-up.
My condo is on the 3rd of 5 floors. I have seen inside the walls that a vent line runs down and also up above to the 5th floor rooftop.

 

[brad0102]

Is the pop up itself coming up high enough. Did you fasten it in with the rod. I usually just drop the popup in so it can be cleaned
out. If it comes up high enough take your p-trap off and see how well it drains into a bucket. If it drains good you probably have a
plug in the line.

agree....the pop-up has to come up high enough to allow air to escape while water attempts to drain......

 

[TomFOhio]

Do like I said even with your new one. Take the trap off and put a bucket under the drain. Fill your sink and see what happens. If it
drains good into the bucket then your line is plugged. If it still goes slow then its your new popup assembly not working right.