The venting is under positive pressure. Therefore, the venting must be tested and approved for positive pressure. Single walled vent connector and B-vent, whether gooped or not is Not approved for positive vent pressure.

I see signs of condensation corroding the joints. Also, inside the cabinet to the left of the inducer appears to be dusty from blowback.

The unit must be approved for horizontal venting.

The vent termination is too close to the windows.

I would want to see the installation manual to see how they propose to vent this unit.
Bob

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