Heating feed/return

[Jever]

Hi,

Is there an easy way to tell which is the feed and which is the return central heating pipe when you have two together?

I took off a rad and capped the pipes and can't remember which was which.

Should have made a note....

TIA

Jever

 

[Dan Robinson]

Link them then turn the system on and note which heats first.

 

[Jever]

I like it, thanks!