Going from Honeywell RTH2410B1001 to 3rd Gen Nest

[silvasp]

OK. Bought a new (old) house. It came with a Nest 3rd Gen ( think), AC works, but,
1.)The fan doesn't seem to come on without the AC when I choose "FAN"

2.) The heater doesn't seem to be coming on either. When I set it to "HEAT", I can hear the igniter sparking, but no fan, and the burners don't come on.
I contacted the old owners and they sent me a picture of the Honeywell wired up
Any help would be greatly appreciated.
(It's a 4-wire system - Yellow, Black, White, Red.)
Honeywell was wired as - Yellow wire on Y -- Red wire on R -- Black wire on G -- White wire on W/AUX
(not used O/B)
Wired on Nest as - Yellow wire on Y1 -- Red wire on Rh -- Black wire on G -- White wire on W1

(not used Rc, OB, Y2, W2/Aux, C, *,)

[luciaaa]

Hi, @silvasp,

Thank you so much for posting in the community. I’m truly sorry the fan is not turning on. Let’s work together and find a solution.

Based on your description, it seems you likely have a conventional HVAC system. To better assist you, I'd appreciate some additional information:

• Are there any error messages displayed on the thermostat?
• When was the last maintenance check for your HVAC system?
• When did you first notice the fan not working properly?
• Was the Nest recently installed, or has it been working previously?

Here are some Here are some initial troubleshooting steps you can try:

• Ensure all the thermostat wires are securely inserted into the correct terminals.
• Restart the thermostat by pressing and holding the ring for 10 seconds until the screen turns off, then release it.

If previous troubleshooting steps didn't work, try these steps:

• Turn off the breakers for your HVAC system.
• Swap the Y1 and G wires (yellow and green).
• Turn on the breakers.
• Reattach the thermostat and set the system to cooling mode, expecting the fan to turn on.

Please let me know how it goes.

Best regards,

Ana