Upgrading to Nest thermostat problems
#1
Member
Thread Starter
Upgrading to Nest thermostat problems
A few days ago I ended up buying a Nest Gen 3 thermostat . Writing down the wires , what they are connected to as well following Nest instructions.
But now there is an issue that the furnace fan does not go on, even though the furnace turns on.
And testing the Nest thermostat the fan sounded like it tried to kick on but never did.
Everything looks like it is wired correctly, I even re-seated the green contact.
Here is pictures of everything for any suggestions on what is wrong.


But now there is an issue that the furnace fan does not go on, even though the furnace turns on.
And testing the Nest thermostat the fan sounded like it tried to kick on but never did.
Everything looks like it is wired correctly, I even re-seated the green contact.
Here is pictures of everything for any suggestions on what is wrong.



Last edited by PJmax; 03-25-19 at 08:06 PM. Reason: cropped/resized/labeled pictures
#2
Welcome to the forums.
Made me work here tonight. Moved thread. Removed second one. Resized pics for the board. You need to pre-size the pics before posting. 600x600 max.
You don't have a furnace...... you have a RHEEM or RUUD heat pump with electric backup.
Is that correct...... NO gas furnace ?
Move the white wire from * to W2/AUX.
Made me work here tonight. Moved thread. Removed second one. Resized pics for the board. You need to pre-size the pics before posting. 600x600 max.
You don't have a furnace...... you have a RHEEM or RUUD heat pump with electric backup.
Is that correct...... NO gas furnace ?
Move the white wire from * to W2/AUX.
#3
Member
Thread Starter
No it is a Rheem natural gas furnace and a Electric heat pump.
Thank you for cleaning up the threads.
There is also a pro setup on the Nest. Have not went through that.'
Attached image is what it current thinks I have connected
Thank you for cleaning up the threads.
There is also a pro setup on the Nest. Have not went through that.'
Attached image is what it current thinks I have connected

Last edited by PJmax; 03-25-19 at 08:42 PM. Reason: resized pic
#4
Ok... you still need to move the white wire.
In pro setup..... you need to program the nest as DUAL FUEL. You need to program the O/B to B.
In pro setup..... you need to program the nest as DUAL FUEL. You need to program the O/B to B.
#6
The reason for the dual fuel programing is because the gas furnace and the heat pump cannot run at the same time. The heat from the furnace will cause the heat pump to overheat.
#7
Member
There probably is a dual fuel board that protected the heat pump. Might also have a outdoor thermostat that controls cut-over.