E1 Error Solution: Re-Pairing the Salus iT800 smart thermostat The E1 Error indicates the thermostat or receiver has been factory reset and the devices are no longer communicating. The solution is to force both units into pairing mode and re-establish the Zigbee connection. Step 1: Prepare the Boiler Receiver You must first put the receiver (the unit connected to the boiler) into pairing mode. Locate Pinhole: Find the small Zigbee pinhole located on the bottom-left side of the receiver. Activate