TBSE on a very long radiator

[phloaw]

I have a 225cm wide, 45cm high radiator on a standard vented, 8mm microbore two-pipe, fully pumped system.

I am getting rid of its old twin entry radiator valve to install a trv, so I need to decide where to position it and the lockshield.

Easiest option would be TBSE (top-bottom, same end) on the left side of the radiator, with a bleeding valve on the top right corner of the radiator.

However, intuitively, I imagine that with such a long radiator, even if the circuit is pumped, hot water could have a hard time getting from the left end to the right end of the radiator if both valves are on the left end.

 

Does this make sense, or TBSE will work nevertheless?

 

Thanks!