What brand of Tstat is that?
It looks like a proprietary type for your heating system.
E1 E2 is probably the communication wires that it sends data to the heating system.
If you go to the furnace and take off the cover look on the back of cover for decal with the wiring info.
You might be able to use a Nest or standard Tstat if there are terminal screws for R W C G in the furnace.
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