-
Some will hold for some hours, yet many slide seals deflate once no supply of aux air remains. So, yes, want a constant supply of aux air to prevent rain water intrusion.
On your Royale, check rear wall of third bay, driver side, behind a carpeted cover to see your slide out controller & air pressure regulator. 10 psi is the set point for original seals. The new 2-piece seals require minimum of 12 psi yet I “think” (an am not certain) they want 14 psi in the new seals and 12psi if have one old seal and one new seal