Refilling underfloor heating

[Plumber noob]

Hi, gotta a bit of an issue with refilling my underfloor heating. Am I right in saying that the flow meters along the manifold should be on the top rail, but as you can see they are at the bottom?
Also have I got to loosen off the electrical actuators at the top to refill the system?

Cheers

 

[Lou]

Can anyone help with this underfloor heating question?