I have tried activities running only the edge and my heart rate shows for the day but not as part of the activity.
I have tried activities running only the edge and my heart rate shows for the day but not as part of the activity.
You have to set you F6 to broadcast HR. Check the manual for exact details on how to do that. One option should be to broadcast during activity. Then when ever you start and activity it will broadcast. Then you can choose which device you save the activity on.
If you set on your watch brodacast always - it will always broadcast and Edge will be able to pick it when both are powered on. (be aware that this will affect battery, of course)
if you set on your watch broadcast during activity - it will only broadcast when you start an activity on your watch. Edge will pick it once you start the activity on the watch. As soon as you stop the activity it should not broadcast anymore.