[solarhotairpanels]

Hello MikeSolar,

Thanks for jumping in here.

I use an old 6 gallon water heater for my drain back tank.
My systems is built using all 3/4 copper pipe up to and return from collector.
No check valves in my circulator pump.

During testing after the build my return water took forever to return all water to my drainback tank after my pump was shut down.

I had to add a T fitting to the return piping where it entered the drainback tank and stick a ball valve on the end of the T which I leave cracked open just a tiny bit.

With the ball valve cracked open my water returns from the collectors almost instantly.
You can hear it gushing into the tank.

I don't run glycol with my system... just water and dont' want to take any chances of it freezing so even though you have documented 1000's of them working fine in Europe with no air allowed into the system.. I have to stick with this current design until I see a design like you are talking about.

and honestly? I'd love to see how they're doing that if you could send me a layout of their design... I assure you, I'd well appreciate it.
no vacum lock? at all? that's amazing.

Just about every drainback system I've seen online and those seen in person prior to building my own system allows air into the return pipe or somewhere on the system in order for the water to drain back more quickly.