Promote replica to master and rebuild old applicance as replica

[RSAVarela]

I am in the process of making sure that nothing in our environment hits the primary node.  We ordered a new appliance and added it as a replica.  Is it possible to promote the new replica to Primary and take the old primary node and make it just a replica?  Will a reset of the appliance need to be done on the old primary or will it be downgraded to a replica once the new Primary is complete?  I am trying to plan this out before I do it.  Since the old primary has a lot of applications tied to that ip, I did not what to move all the applications. 

Current

Primary---replica

Future

Primary (New Appliance promoted replica)---replica (old primary)---replica

Thank you for your time and help.

[EdwardDavis]

If they are same version and patch, and replicate now, then you can do a 'planned promotion' where

you make the replica a primary, and then make the old primary a replica, without major reinstall. see disaster recovery 

or planned promotion in the admin guide. essentially flip roles.

[RSAVarela]

Thank you.