I did not put the loops in order..I figured out he had a 3/4 feed the washer, 3/4 to water heatr and 3/4 to bathroom
did not need to put them on the exact number.
You should, so you can know which one goes where
But here's my argument.
Stan0228:
"For the pipes behind washer, I found pipe #3 should be the pipe coming from the mainline
(because when I cut the pipe #3 and end cap the bottom,
there is no cold/hot water inside the whole house as well as the outside faucet in the backyard.)"
We can agree on that.
He cut the loop to the water heater #2
where i got my "clue" from was the picture of the bathroom water..look to the left, you can see 2--3/4 lines loooping in behind the lav.
Stan0228:
Then I tested pipe #2 (after connect pipe #1 back) by cut off pipe #2 and put an end cap at the top.
Now there is still cold water coming out from ALL fixtures in the house including the outside faucet, but NO HOT water at all.
(Later I connected the pipe #2 back and there is hot water in the whole house.)
Does that mean this pipe #2 is connectin to the water heater??
If you cut #2 to WH then in your layout, you would loose cold water to the kitchen. Stan said he had cold every where.
common since tells me. 1 loops in from w/h the other loops to the other bathroom
I have done so many slab leak reroutes that common since gets tossed out the back door
so..either the kitchen loops hot from the other bathroom or from the w/h
he tested that line, varified it was not looped from the 2nd bath.
all that is left is the w/h Again. If he only lost hot when he cut #2 then how does the kitchen get cold water
and, I figure, the cold will be looped the same as the hot
that leaves me, with kitchen h and cold looping from w/h
the t hb...loops off the kitchen
That is a perspective of common since if you had installed it but you didn't.
Sometimes but not always the will run 3/4 to back hose bib for the possibility of installing an irrigation system for the back yard.