https://www.928gt.com/T-WallyHVAC.aspx
You will get some leakage via the valve if your arm is not closed when air is set to cold then use a mighty vac and check. Vacuum comes from the controller.
You need to indicate you're year on your signature, depends on year but outside and inside sensors come into play.
Blower should not cycle check your connections and take time to read this link.
