vision pro thermostat

[lkaufman]

Hi,

I recently installed a honeywell vision pro thermostat with the optional outside sensor. At first I used 2 extra conductors in my thermostat wire for the outside sensor but got some wacky reading. I ran a seperate shielded 2 conductor 18 ga cable just for the outside sensor. When I connected the sensor to the first thermostat everything was working great, when I connected the wire to the second stat I am reading 100+ degrees when it is 17 outside. Both were wired using the same 18/2 shielded cable?

Thanks

[lkaufman]

Ok, some more information from testing. I have two seperate shielded 18/2 cables running from each thermostat to the basement. If I connect either to the outside sensor it works perfectly so I know there is no interference on either cable. The problem is when I connect both cables from the stat to the outside sensor, the temperature goes nuts. Is a diode needed?

Thanks

[lkaufman]

Is it possible that the outdoor sensor will only support 1 thermostat (2 sensors for 2 stats). I thought the resistance it measured would be the same?

[jlkelly]

Originally posted by lkaufman
The problem is when I connect both cables from the stat to the outside sensor, the temperature goes nuts. Is a diode needed?

HA HA HA HA HA HA ROFLMAO

[BaldLoonie]

1 sensor can't be used on 2 stats. Lucky nothing has been damaged.