New Nest 4th red wire issue

[Kathyofit]

I am trying to install Google Nest Learning Thermostat 4th generation. Upon installing the thermostat, it shows “no power” for the red wire and gives me an error E448. I tried shifting from Rc to Rh but still no luck because my previous unit had a jumper between the Rc and Rh. I would appreciate any advice on how to tackle this matter.

[Patrick_Caezza]

@Kathyofit 

Do you have a furnace/heat pump or a boiler?

Can you post a picture of the original thermostat's wiring here?

If the camera icon isn't present yet, you can use the imgur.com upload site and post the link it provides here.

[Kathyofit]

I determined the issue, but now I have another problem.  I only have a Heat option on the app and not Cooling.  I'll have to verify that my unit is compatible and that the C wire is connected well enough.  I regret that this gen 4 is too new for my system.