Overloading geothermal system with addition
I have a 5-ton ground source heat pump with 5 200' wells. This uses 2 pumps: a 3-ton for my lower floor and a 2-ton for the upper floor. The system has been verified to be right-sized for my house which is 3300 sq ft.
I'm adding 600 sq ft to the house and am looking for options. Here are a couple that come to mind:
1. Re-route some vents to the new areas. Might overwork system or not heat evenly.
2. Add 1 ton total furnace but don't add a well. Might overtax wells.
3. Add 1 ton and add a well. The right way but expensive and annoying (dig up yard).
4. Install a completely independent system for the new areas.