New Nest 4th Gen turning on AC & Furnace at the same time

[DIY_Bob]

I just replaced a Honeywell learning thermostat with a Nest 4th Gen Learning Thermostat + temperature sensor. Everything worked fine with the old thermostat but my wife bought this new one as a Christmas gift and so I thought I’d better use it and this should be a simple install. However, on a cold day yesterday I tried installing the unit annd everything went well except when I turned the power back on the AC and Furnace turned on at the same time. NOTE: we have a gas AC cooling unit outside the house and a gas furnace in the basement for heat.
As for wire mapping, from the old thermostat to the new, there is only a Y wire (no Y1 & Y2) so I connected the Y wire to Y1 and in the old unit  there was an Rc and an R. The red wire went into the Rc with a jumper to the R. The OB wire went into the OB connection and the G went into the G as per the labels. 
Given the temp yesterday, I decided to take out the Nest and install the old one until I can figure out the problem. 
Anyone with thoughts on the possible issue?

[Patrick_Caezza]

@DIY_Bob 

Can you post a picture of the original thermostat's wiring if you have one?

Can you also post a picture of how you wired the Nest.

[DIY_Bob]

@Patrick_Caezza @Thanks for your reply. I do have a photo of the old layout but not one of the new. I am new to this forum and can’t seem to find the option to add a photo. I am using an iPad. Any suggestions on uploading photos.

Thx

[Patrick_Caezza]

@DIY_Bob 

You can upload a picture this way.

[DIY_Bob]

@Patrick_Caezza Thanks. That wasn’t available the first time I responded.  Here it is. I don’t have a pic of the wiring I did for Nest unfortunately. 

BTW while I have a furnace for heat and an AC for Cooling, they both use a centralized blower at the Furnace and then the air blows through internal ductwork in the house. 

 

[maedacortez]

Hi DIY_Bob,

Thanks for reaching out. I understand that you need help checking if you connected all the wire labels correctly, and I'm happy to assist you!

You mentioned that you have a jumper with R and Rc. Please note that you do not need to install the jumper wire on the Nest Learning Thermostat. Please let me know if you did not connect the jumper wire on your Nest Learning Thermostat.

I'll be awaiting your response.

Regards,

Manuel

[DIY_Bob]

@maedacortez Don’t think I did an effective job with my first description. In the old unit the Red Rc wire went into the Rc slot and there was a jumper between Rc and R. The white OB wire went into OB slot, the Green wire went into the G slot and the Black wire went into the Y slot. 

I did not use the jumper in the Nest thermostat, correct.

Sorry for the confusion.