As of the 2026–27 season ·: A guide from the Bergfritz team.
Did you get some new Lenz heated socks? Here's a step-by-step guide on how to get started.
1. Charge the batteries first
Fully charge the batteries before using them for the first time. Connect the USB charging cable to a power adapter with at least 1 A, and attach the batteries using the snap buttons. When the indicator on the cable is green, they are fully charged. The batteries charge only at room temperature, between 10 and 30 °C.
2. Put on your socks, plug in the battery
Put on the socks so they're wrinkle-free, with the heel aligned with the heel. Then snap the battery into place using the snaps on the sock cuff.
3. Turn it on and select a setting
Press the button on the battery for a moment until the light turns on. Each time you press it, you’ll cycle through the settings—from the first to the second to the third. Tip: Turn it on at the lowest setting as soon as you start walking. It’s hard to warm up a body that’s already gotten cold.
4. Pair with the Lenz Heat app (rcB 1400 and rcB 2000)
Download the free Lenz Heat app from the App Store or Google Play, turn on Bluetooth, and pair the batteries in the app. This video from Lenz shows you how:
In the app, you can adjust the settings more precisely than with the three levels on the battery—up to 9 levels. You can control the left and right socks separately, view the charge level, and turn on interval heating, which turns on and off every few minutes. This helps the battery last even longer.
If the app can't find the battery
- Close the app and reopen it, restart your phone, then pair it again.
- Many cell phones can connect to only 6 to 10 Bluetooth devices at a time. Remove any devices you don't need.
- On Android 6 through 11, location services must be enabled for Bluetooth to work. According to Lenz, the app does not collect any location data.
To Keep It Warm
- Dry Ski Boots: Wet shoes significantly reduce warmth. Read more in the article " Drying Ski Boots and Gloves."
- The Right Size: Heated socks fit snugly so that the heating element is close to your feet. You can find help in the heated socks guide.
- Runtimes, Charging, and Storage: Lenz Batteries Explained.
Frequently Asked Questions
How do I turn on Lenz heated socks?
Press the button on the battery for a moment until the light turns on. Each time you press it, you'll move to the next of the three levels.
How do I pair the batteries with the Lenz Heat app?
Download the app from the App Store or Google Play, turn on Bluetooth, and pair the batteries in the app. This works with the rcB 1400 and rcB 2000.
What does the Lenz Heat app offer?
More precise settings than on the battery, separate controls for the left and right sides, a charge level indicator, and an interval heating feature that extends the battery's life.
The app can't find my battery. What should I do?
Restart the app and your phone, then pair them again. Check to see if too many Bluetooth devices are connected, and for Android 6 through 11, check to see if location services are turned on.
