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Tacx Flow Smart Trainer: Light Flashing Red After Intense Workout

While in ERG mode if you are training above 250 watts for a prolonged period of time the trainer may go into an overheating protection mode. If this happens the resistance on the trainer may cease while the trainer cools down. In order to avoid this issue we suggest that you increase your speed during your workout by riding in a larger gear, resulting in an increased flywheel speed. Doing this allows the brake to decrease the resistance amount for your workout and in turn allows the trainer to operate at a cooler temperature.

You may also see this if riding in slope mode during a sustained climbed during a virtual ride. You can reduce the slope in the app to allow you to ride in a larger gear gear on climbs to keep the flywheel speed higher allowing the trainer to operate at a cooler temperature.