American Standard 624 Thermostat Humidity Reporting Issue

I have an American Standard 624 Thermostat (TCONT624) which is the same as the Trane XL624, and love it. Works great with Indigo. The only issue I've found is a minor one. When Indigo polls the device for status or when I press the button to send a status request. the humidity value is not returned. All other values are returned as expected. Here's a snippet of the log file:

Raw command sent (Node 25): 01 09 00 13 19 02 45 02 25 D9 45 (True)
sent "Thermostat" fan state status request
received "Thermostat" fan is on
Raw command received (Node 25): 01 09 00 04 00 19 03 45 03 01 AF
Raw command sent (Node 25): 01 0A 00 13 19 03 31 04 05 25 DA 33 (True)
sent "Thermostat" humidity status request
Raw command sent (Node 25): 01 09 00 13 19 02 31 04 25 DB 35 (True)
sent "Thermostat" temperature status request
received "Thermostat" temperature update to 67 °F
Raw command received (Node 25): 01 0B 00 04 00 19 05 31 05 01 09 43 93
Raw command sent (Node 25): 01 0A 00 13 19 03 43 02 01 25 DC 45 (True)
sent "Thermostat" heat setpoint status request
received "Thermostat" heat setpoint is 70 °F
Raw command received (Node 25): 01 0B 00 04 00 19 05 43 03 01 09 46 E2

If I manually send the exact same raw Z-Wave command, the correct response is returned:

sent "Thermostat" raw command [31 04 05 25]
Raw command sent (Node 25): 01 0B 00 13 19 04 31 04 05 25 25 DE 14 (True)
received "Thermostat" humidity update to 44%
Raw command received (Node 25): 01 0B 00 04 00 19 05 31 05 05 01 2C F0

This does not make sense to me. The only thing I've been able to find is that the request is not being send entirely correct. The command being send is:

0x31 0x04 0x05 0x25

0x31-COMMAND_CLASS_SENSOR_MULTILEVEL
0x04-SENSOR_MULTILEVEL_GET
0x05-Sensor Type of Humidity
0x25-Scale (0010 0101)

Reserved 001
Scale 00: Percentage value (%)
Reserved 101

According to the Z-Wave specifications concerning the "Reserved" fields, "These fields MUST be set to 0 by a sending node and MUST be ignored by a receiving node." I would think the more correct code to send would be: 0x31 0x04 0x05 0x00. This sets the "Reserved" fields to 0. With that said though, the specification also says that the receiving node should ignore a non-zero value. Therefor, it shouldn't really matter.

Any thoughts as to why the humidity values is not being returned correctly?

Thanks,

-Tommy

[matt (support)]

Hi Tommy,

Indigo is actually sending 31 04 05 in this case (the 25 is actually the transmit flags byte). I don't believe that is quite up to spec, but most modules assume scale byte of 00 if it isn't included apparently. However, the TCON624 isn't liking that based on your log snippet above. I'll tweak it to add on the 00 byte and I suspect that will fix the problem, which would be the same as you sending the raw command 0x31 0x04 0x05 0x00.

Ah yes... understood. I tested by sending the raw command 0x31 0x04 0x05 and there was no response.

Thanks, Matt!

[matt (support)]

Indigo 7.4.1 is now available and should poll out the humidity correctly now for this thermostat.

Works like a charm now. Thanks!