Wifi thermostat for temp a trol zone system

[RonH]

I have a 2 zone Honeywell temp a trol system. I'd like to replace the existing programmable thermostats with wifi stats. The existing stats are Chronotherm iii. Main level has heat/cool and fan selections. Upper level programs separately, but no heat/cool or fan control. Upper stat has 3wires W, R, Y.

[Paul Z.]

You will need to replace that zone panel. Have a few questions please call 1-800-446-3110 X490/

[Paul Z.]

You will need to replace that zone panel. Have a few questions please call 1-800-446-3110 X490.

[timothycobb]

I agree with Paul you need to replace the zone panel. This replacement is quite a difficult task, therefore it would be better if you take professional help and get more information for replacing the existing programmable thermostats with wifi stats so that your system will work functionally.