479-648-4900: Rheem Customer Service Phone Number in USA

Had compressor go on heat pump and not happy under warranty hold it would be 6 months to get parts is this right ?

Hello,

I have an Old RHEEM HVAC unit which is running fine but The model number tag is missing. I need your help to identify the model or potential model numbers for maintenance purpose.
Here is some info about the unit.
The house was built in 1980 so the Manufacturing date may a year earlier.
The Air handler (furnace) tags are intact.
The furnace model number is RGBA-12EC
Sr. Number TN3D107FO7790593 Factory: Fort Smith Arkansas.
I can send marking on the compressor or a picture of the unit if it helps.
If a schematic of the outdoor unit available, I would like to get that.

Thanks
Haresh Patel