CT-30 from 2 Gig interferes with network

This is the second time I’ve had my network crash (lose some scene devices, devices won’t configure, scene controllers don’t work, can’t add devices). I pulled the radio out of my CT-30 both times and everything was happy again… instantly. Any idea if there is a fix for this? Preferably without replacing the thermostat.

I ran into the same issue and got the following response:

“I’ve checked your unit and as far as I can see there seems to be a source of interference for your z-wave devices.
Can you please tell me the model of your 2GIG thermostat, as we had issues with the CT-30 thermostats, as they are known for flooding the z-wave network and causing it to break down? If this is the case then please use the attached document which was given to us by Radio Thermostat to exclude and re-include your thermostat as a battery operated device so it will stop flooding the z-wave network.”

I tried the work around but still doesn’t fix it. My controller does not connect to “C” wire and is battery operated so I just left it out. Just in case, below is the instruction. Hope it works for you.

Issue Description:
There is a known issue with v7.4 of RTCOA Z-Wave firmware that will cause thermostats to constantly transmit on the Z-Wave network. This constant transmit condition will cause communication failures not only with the thermostat itself, but other Z-Wave nodes in proximity to the thermostat. This issue has been known to occur only on thermostats joined as always listening devices (c-wire) with moderate to large z-wave networks. This race condition is only present in v7.4 and has been eliminated in all
subsequent firmware versions.

If the user suspects that the thermostat is in this state because of network communication failures, reset the thermostat and check the Z-Wave network again. If Z-Wave network communication is restored, then issue is the likely cause of the communication failures. This issue only happens on thermostats powered via the c-wire with a Z-Wave USNAP module v7.4.

Work Around: Instructions to join thermostat as a battery powered device

  1. Exclude the thermostat from the Z-Wave network.

  2. Turn off HVAC power.

  3. Disconnect the C-Wire.

  4. Reset the thermostat and wait 10 seconds.

a. The reset button is located underneath the top wire cover.

  1. Include the thermostat to the Z-Wave network.

  2. Verify that the thermostat has successfully joined as a battery-powered device.

a. The radio version should say ?7.40?.

  1. Reconnect the C-Wire.

  2. Restore HVAC power.

How to determine Radio Version and C-Wire/Battery Status

  1. Put thermostat in OFF mode

  2. Press and hold lower right corner of LCD for 5 seconds

  3. Text will appear in the upper left corner of the LCD. This text area displays the thermostat firmware version and the firmware version of the USNAP radio modules. Press the up or down buttons on the LCD to cycle between the versions.
    a. Fx.yz : Thermostat firmware version (e.g. F1.92 is thermostat firmware version 1.92)
    b. L z.yz : Firmware version of left USNAP radio module (if present).
    c. R z.yz : Firmware version of right USNAP radio module (if present)

  4. The last digit of the radio version represents the c-wire/battery status. If the digit is ?1?, the thermostat is mated with c-wire. If the digit is ?0?, the thermostat is mated with battery.
    a. ?7.41? : USNAP v7.4, mated with C-Wire
    b. ?7.40? : USNAP v7.4, mated with battery

See also this topic.