Trane Communicating System

[jason12000]

I installed a Honeywell TrueSteam Humidifier on a Trane XC80 furnace. Model TUD2C080ACV42AA, 3yrs old. Following the Honeywell installation using an interface module to run my stat (D,R,B), hum, and osa sensor through. Then my stat connections W, W2, G, Y, R, C to my furnace. Programmed the stat Focus Pro IAQ, (o.g. Trane ComfortLink 2) No comm when calling. Getting 24V on G and W when calling for Humidity and heat. Circuit board is not recognizing the 24V on the W or G terminals because it's set up for the Data wire. Spoke to Trane and they said that you can't use the Honeywell interface module. Rewired back to original wiring. ComfortLink 2 stat to Furnace D, R, B. Now in order to run my humidifier off of fan (variable speed) I was told to use the 120V molex plug in the center of board - to transformer - to relay - to humidifier. My question is; Is this the only solution to this issue? It seems to me that the communicating system should be more compatible with this equipment. Is there a dip switch somewhere to allow me to utilize the board connections? There are no HUM, or EAC post on this board. By the way, customer provided all honeywell equip. I know, not my call. Thanks for any advice.

[lash61101]

I'm new to the field and not sure about the Honeywell tstat process. But, my job usually just uses a relay to power the fan to turn on when called for humidity. Which could be wires from a humidistat. But also should have a air proven switch wired in. Just my knowledge, I'm still learning and there may be a better option. Hope I helped somehow.

[jason12000]

Thanks for the response lash61101. I resolved the issue. The communicating system on this furnace has EAC, and HUM wiring in the j-box. It's 120V though. Even the tech. support had me going through the fan 120v (EAC) to modify the signal to the humidifier. I used the HUM blk and wht 120V wires, to transformer, to relay that is now 24v control for the humidifier. Now when there's a call for humidity the data wire sends the signal to the furnace board, which sends the 120V to HUM blk and wht, etc. This set up did not use a proving switch. I still have a question of why it uses 120V as it's control voltage instead of 24. I did get to learn more about the communicating systems in the process.