Upside-Down Manifold

I dont have the exact answer for why, but my logic is, especially for radiant floor line applications I think it would be a bad idea, becuase you will never be able to trap air to remove it from the system. My 10 port Stainless Rehfing manifold is in my basement, and all my radiant floor loops, and radiators are above it. I swept all the lines out the side of the manifold then upward into the house and it has made for a decent installation.

check with the manufacturer, generally it is ok. With our manifolds the only time we don't approve upside down mounting is in a chilled water application. In that case condensation can trickle down and get into the electric actuators that hang below at the lowest point. The accuators as well as the flow meters will work in any position.

If it has an float type air vent on the manifold, that needs to be rotated to an upright position of course.

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