++Please help, radiator on loop not working++

[andyK]

Hi All,

I've installed three recessed cast iron radiators on the second floor of my house and the water is refusing to run all the way through the loop.
I'm suspecting that it might be an issue with trapped air although I've fully bled all three units. Any help or suggestions are really appreciated!

Just some details:

I'm using 3/4" PEX. Line from the 2nd to 3rd radiator goes up and over a doorway.
Return line comes back over the doorway as well before going back down to the boiler
on the first floor. I've drawn a diagram that'll hopefully help.

Thanks again,
Andy

 

[plumbitright]

If you can't seem to get the air out, which is likely the problem, you may need to cut an air bleeder into he highest point of the loop, bleeders on the rads themselves may not be enough.

 

[frodo]

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