Gravity feeding upwards??

[NOLAGT]

The door will still be in use, so to drill through the door is not that simple. Hmmm, I could cut a square out of the door and fix the square to the frame and fit the plumbing through the square, so that when the door opens the plumbing stays put.

Thanks for all the info and help guys

I would do it that way if it were me. Its just that U that is the problem for me

 

[Toby_H]

I agree that the bends in the piping will slow down flow…

But the extra bit of lift on the balcony side of the door will not… because the water will gain momentum on the tank side of the door by dropping further… The extra lift and the extra momentum will balance each other… leaving only the bends to slow it down…

But all of this can be taken into account and adjusted for when setting up the system. I would always suggest using a ball valve on a pump return to it could be dialed back if it proves to strong.

I see absolutely no reason anyone should expect this set up to fall out of balance than any other system.

While functionally speaking, I do agree that having the pipes go through the door higher would be better, as it would remove two 90* bends… I also understand aesthetically this may not be practical.

 

[cypher1024]

I'm not particularly smart, so I could be wrong on this but I was under the impression that a U like that shouldn't affect the flow rate too much. Sure, the extra elbows and pipe length will slow the flow a bit due to friction but since gravity is acting equally on both sides of the U, any resistance on the output side should be matched by the force of the water on the input side.

Even if I'm wrong, from your illustration it looks like some water could build up in the long downpipe, forcing water through the U faster and faster until it reaches equilibrium (which should be far from the water level in the tank).