Air to air exchanger with two thermal zone

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I'm interested in modeling an air loop between 3 thermal zones using OS 3.4.0 and E+ 22.1 that includes zone mixing and outdoor air heat recovery from a zone before entering another zone (see schematic bellow).

I have good experience with OS but limited with E+, so I'm not even sure if this air loop is possible.

The challenge #1 is to send the air from Zone 1 and Zone 2 to Zone 3. I made it work with the objects: ZoneInfiltration, ZoneMixing and ZoneExhaust in E+.

The challenge #2 is to recovery the exhaust air from Zone 3 to preheat the outdoor air going in Zone 1 and Zone 2 with an HeatExchanger:AirToAir.

If this air loop with three thermal zone is not possible, would it be possible by excluding thermal zone 2 ? By creating nodes and using an air to air heat exchanger ?

Thanks,