Trane tracker to TCI comm loss
Can a bad zone sensor cause comm failure? also If there is comm loss would the fan be enabled? I think I have a wire issue, but voltages, frequencies are the same at all comm link connection points.
This setup is simple 2 units w/ tci 3 boards and one tracker panel. One unit has lost comm. Swapped tci boards and that did not work. same unit stayed in communication. I think the problem is the comm link that goes between the 2 units. ucp functions all work in test. leds on the tci board intermittenly flash. I'm at a loss as to where to go from here. Planning on running a temp wire between the units to see if i can reestablish communication to the 1 unit. any suggestions would help.
If these units have economizer I would disconnect that first (Molex plug), then reboot everything and see if it starts working.
Is this brand new? 2nd unit never worked, or is this existing that its gone down recently.
A zone sensor failure should not cause comm loss. If you have comm wire going down to the jack on the stat then you could have a issue there.
Believe TCI do last command on comm loss, so if it was off, it will stay off. Could be wrong dont quote me.
After you try the econ module like kevin said i would just take your wires off and ohm them out, make sure you dont have a short between them or to ground on the link between units.
Also make sure no one has bumped the address on it, i know it is unlikely but you never know what people do, maybe somebody was playing with the dip switches.
Thanks for the responces, it was a failed zone sensor. I thought that unit 1 had lost communication, but it had not. I was mislead by a reoccuring fault code on the tracker display. It kept telling me that TCM UNIT 1 DEVICE NOT COMMUNICATING. I took that to mean that the TCI in unit 1 was not communicating. Apparantly the TCM it said was in comm loss is being used as a lighting control which fails to having the lights on all the time, which I'm not worried about. What tipped me off was that the units fan continued to run telling me it was in communication. The zone sensor ohmed to OL, so I borrowed the O.A sensor for low ambient control, mounted it in the return air, and all now works normally. Still need to go back to replace zone sensors.