Wiring aprilaire 700 with ecobee3 PEK (only 4 wires in the wall)


Old 12-17-16, 05:40 AM
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Wiring aprilaire 700 with ecobee3 PEK (only 4 wires in the wall)

I have similar problem. I have aprilaire 700 humidifair with automatic humidistat. I instalid it muself while ago and works perfect. It automaticaly uses furnace blower with no call for heat if needed. The humidistat requres use of G termostat wire as per aprilaire 700 diagram. Pic is here

Recently i purchased ecobee3 thermostat. I have only 4 wires in a wall , no C common so i have to use PEK power extention kit from Ecobee. Ecobee also provides instruction how to connct humidifer, but it requres additional wire or wires to the thermostat acc- and acc+ terminals, which i obvously dont have. To pull additional wires would requre tearing walls and cillings on 2 floors. And i Do Not want exobee to control my humidifier anyway. Aprilair auto humidistat does it perfect

So i con ected PEK wires as per ecobee instructions except G thermostat wire which was already connectd to the humidistat G wire as per aprilair wiring diagram. For that i just used Connected these two TOGETHER to the PEK G terminal. U fortunately this didnt work. The ecobee3 has been going through revoot like a computer each time i touch it and furnice didnt work. The temp droped to62 so i just disconected completely humidifier all wires and connected ecobee3 and PEK. Now everything works fine but humidifier is completely out.
Need help to wire this properly given i dont have extra thermostat wires in a wall, just 4 and dont want if i can avoid to have exobee3 control my humidifier.

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Old 12-17-16, 11:42 AM
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I resolved. Apperently i was making mistake how i connected G thermostat wire, G aprilair 700 automatic humidistat terminal and ecobee3 PAK thermostate side G terminal. Since before ecobee3 i had humidistat G wire and thermostat G wire conncted as per the aprilaire wiring diagram, i just tied 3rd G from PAK thermostate side G terminal. Wrong!
I needed to connect THHERMOSTAT G wire to the PAK thermostat side G termnal as per ecobee instruction. Also, instead connecting ecobee3 PAK FURNICE SIDE G wire to the furnice G terminal, I needed just to tie THIS WIRE together WITH humidistat G wire. THATS IT. Now everythig works as it suppose to and my humidifier is controled by the humidistat which has outdoor humidity sensor connected. This is my preference and better way then having ecobee3 controling humidity.

Hope somebody out there will find this troublshooting usefull
Old 12-17-16, 11:49 AM
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Good job.

Since I'm in the business I don't use those PEK modules.... I pull a new cable.
I also do not allow the humidistat to turn the blower on. I've found that there is not enough heat to cost effectively move humidified air..... which wastes excessive water.
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