Incorrect HR from a Garmin HR device

I have a Garmin (ANT+) HR device that I’ve used for a few years on my bike with a Garmin 1000 unit. It works fine in this environment. I’ve paired it on Zwift - I’m running Zwift on a Mac Book Air with an ANT+ dongle) and although I get a HR signal on Zwift, the actual HR itself is miles off (it’s too low). As an example Zwift might show my HR as 66bpm but if I measure it using the old fashioned method (fingers against neck) it’s closer to 145-150bpm.

Has anyone else come across this or found a way to solve it?

Garmin HR straps have a history of power spikes and or not reading HR for a period of time. Throw it out and buy something like a Tickr. I used to run Garmin straps and had problems. Things are much more reliable now that I’m using a Wahoo Tickr.

I would definitely try replacing the battery.

Thanks to both of you. The Garmin has a brand new battery so I don’t think it’s that. I’ll try doing a session with a Wahoo Tickr. Meanwhile I’ve sent Zwift the log files from my sessions to help them try to determine what the problem has is.

The Wahoo Tickr works perfectly. Don’t know why the Garmin device doesn’t function properly.

hi, I am having the exact same problem.

zwift with garmin vivoactive hr and tacx

my average hr during the ride is 75, which is way too low. 

the watch works perfect outside my swift setup. 

i am using a PC with a garmin ant+ dongle and the tacx trainer connects flawless. 


any advice?

Vivoactive HR watch - same problem.  Average Hr during strenuous ride is +/- 75 when I know it should be double that.  Using Mac O/S.