I am having weird issues with my Garmin Edge 820 heart rate monitor. I began using the heart rate monitor recently on my indoor trainer, a CycleOps Magneto trainer (about 13 years old). I wet the HR strap with warm water add some EKG gel to the underside of the strap and put it on where it should be. Both the strap label and the transmitter label are up as they should be.
The heart monitor shows my heart rate correctly for the first three to five minutes as I warm up on the trainer. The Edge 820 records my heart rate correctly showing it increasing as I warm up. However at the three to five minute mark, it stops displaying any heart rate. It still shows my speed (wheel sensor), my cadence (sensor) and my power (Powertap P1 pedals) all correctly. It is just the heart rate that is not showing up.
I do not have a television turn on, nor do I have a radio, or even a fan turned on. As I cool down at the end of the ride the HR once again begins to display, but it is sporadic and always way under what my heart rate really is. For example, I am pretty sure that during my cool down my heart rate is not in the 50’s. I am pretty sure it is in the 110 to 120 range. The HR strap never moves form the original position. On one ride I did try to swing the strap around so the pick up/transmitter was on my back but still nothing.
Garmin replaced the HR strap and transmitter with the exact same results. HR is displayed for a few minutes then stops during the entire ride. Some value does reappear as I cool down but again with inaccurate results.
I also downloaded an Android app to my phone that can read heart rate from an Ant+ device and it also had the same drops at the same time. I believe I have ruled out the strap, transmitter as I have used at least two different ones, I think I have ruled out the Edge 820 computer as I get the same results on the Android app. I do not have any music, television, wireless speakers or fans running or turned on while I am riding. Any thoughts?
