Pex and 2x6 studs

I'm running some 1/2" Pex for radiant panel heating through a wall. Since the wall is 2x6 construction I assume it is load bearing. I have access to the top 7†of the wall, just above a fire block made of horizontal 2x6. My questions are:

1. Should I run the supply and return Pex through the same hole (probably 1 ½â€), or two separate holes (probably two ¾â€)?

2. There is already an electric cable through some of the studs, is it ok to have three ¾†holes in the same top 7†of the stud?

Thanks!

make separate holes

I personally would not run the supply and return
lines in the same hole,...

just do 2.... 3/4 holes and it will give you enough flex
and not put any stress or squeaking in the pipes......

I made that mistake a long time ago ,
running everything in a chase touching up against each other .......lots of
the heat can transfer over to the return line. ...and its very inneficient....

it was a very dump mistake ........one of my personal best......

and god help you if you have a cold or hot water
line anywhere near the system...that can really mess things up
in the plumbing side of things with heat transferring .

turning the water going to the toilet hot....is not good.....