EWC Controls Forum

Looks like I may have figured it out but wanted to check. After the switch is installed I need to run a Common from each now slave T-Stat to the NEST to provide power. In metering the lines the Y1 has no juice when the switch is set to HEAT and vice-vera, but this seems to avoid the NEST power issue...

So here is the thing I found. the NEST looks for Power on Yellow FIRST then white. If no power is on yellow it errors out. You only GET power on yellow if the summer winter switch is set to SUMMER, but in the winter the NEST sees power but only on the White and you need to remove the yellow wire for...

It looks like all that is needed is this switch: http://www.ewccontrols.com/acrobat/090375a0222.pdf For about $40 it seems easier and less expensive than changing the panel out. I live in NH and we have a clear line between heating and cooling so we don't usually flip real time between them. In that...