We were using the ZigBee protocol for the mesh network but it looks like DigiMesh is a better option. With ZigBee, all the nodes in the network need to be on all the time to receive messages, but with DigiMesh, they can sleep most of the time, and then wake up in synchrony to transmit signals at a predetermined time. This means our battery life could potentially be over a year.
If we want our heat logs to hold up in court, we’ll have to be able to verify that our sensor readings are accurate. Having tenants have to change batteries in the middle of heat season would involve opening up the sensor, changing the battery, and then re-applying the tamper proof tape, but if the batteries could last an entire season it would eliminate that need. Plus, we want the sensors to be as easy to use as possible - basically “set it and forget it” - and this would mean tenants could do just that and not have to worry about the sensor at all once its installed.