This dual stage system is working fine and is installed under the house. The existing power vent (PV) was used with the new Carrier Infinity system. The furnace has its own exhaust and the PV works with it and the PV is wired into the furnace circuit board.
Every time the furnace cuts on, the PV runs for 30 seconds and cuts out. When the furnace runs in the second stage, the PV runs constantly, which is fine. Why is the PV running for 30 seconds in the low stage when it isn't necessary? The installing company has very poor service. I told them to call Carrier and ask about the wiring but they have not thus far. Anyone have a similar issue?