Balancing radiators.

[NotaBene1210]

I've finally gotten round to balancing the radiators before winter. Everything was going fine with the first 4 rads on the downstairs loop until I got to the downstairs bathroom which has a modern chrome straight radiator. Both valves look exactly the same and there is nothing on either or the caps to distinguish between them. All the other radiators in the house have +/- symbols so it's easy to see which is the lockshield. My question is this.... is there an order of opening and closing the valves in order for me to determine which is which. I'll post some photos and any help would be greatly appreciated. Thanks.

 

[yorksbuilder]

Common for towel rails to have the same valve at each side.
Think of them both as a lockshield.
Open them both, turn on the heating, and see which pipe heats up first. Treat that side as your 'trv' and the other side as your 'lockshield.
Bear in mind that often towel rails are a good heat sink for the system and you may want them hotter than your radiators.
On all my towel rails I have both valves fully opened, and radiators all balanced as normal. Just prefer it this way

 

[NotaBene1210]

Thanks for the quick reply. Appreciate it.

 

[opps]

What's with the "jump" leads?