Install help to attach T style pipe setup on cold side of water heater

[Joe V]

I found slight leaks around cold side input of our water heater. This input has T style connectors where the expansion tank is connected to horizontal portion. I couldn't turn it enough to make it tight because that requires turning the whole T with expansion tank. That wasn't possible. So I removed the expansion tank and then unscrewed the T setup. Cleaned up the whole thing and now I am ready to install it.
Attached is picture of it soaking in vinegar liquid to get rid of gunk in the threads.
I attached second picture with my question as the description below may be too verbose to understand.
I want to unscrew the horizontal section from the T that goes to the expansion tank first. Then screw the vertical section on to cold input of water heater. This is where I need help what the tricks are. As you see, the horizontal pipe has to be screwed into the vertical section so that it points to the open area above tank for attaching expansion tank.
But when you start turning the vertical pipe, how do you start it so that the female pipe thread that the horizontal section threads into ends up at the right spot?
I want the vertical section be tight to prevent future leaks plus the female thread portion stop at right location for horizontal pipe to be fit in later.

The experienced installers probably have ways to do this right. I am wondering what those tricks are.

Thanks

 

[wwhitney]

I assume you must have a flexible connector or union at the top left of that assembly? As otherwise you couldn't tighten the tee on to the water heater nipple while also making up that top connection.

Anyway, the short answer to your question is that threaded connections should have a range of at least 1 turn between "tight enough" and "too tight". So you go to "tight enough" and then continue turning until you have it pointed the way you want.

That's the theory, occasionally in practice it feels like you get to "too tight" before reaching the desired orientation.

Also, with water heater nipples, some tanks come with short male stubs that are too short to get a wrench on to hold back--not sure what the best practice is in that case.

Cheers, Wayne

 

[Sponsor]

 

[Joe V]

Yes. You are right. I have a flex connector that goes on top left.

 

[Fitter30]

You need two pipe wrenches. One to turn the fittings the other to hold back the stationery fitting so the stationery fitting doesn't turn and put pressure on the rest of the piping. Connections don't have to be super tight if you don't think the fitting can be turned a full turn don't. Let the pipe dope do its work. I like either anaerobic or Hercules megalock.

 

[Joe V]

If I understand the responses, I should turn the vertical pipe thingy to a point where I have room to to make one more turn, but don't necessarily tighten it. Given this room to turn it either direction, orient the vertical pipe so that the horizontal can be screwed to it at right location.

 

[Joe V]

Is there a better way to do this instead of this T thingy?
I remember seeing compression style fittings with copper pipes. Are they recommended for water heater connections?