* Underneath the rear seat: A common location.
* In a sidewall cabinet: Often found in vans with built-in cabinetry.
* In the rear cargo area: Possibly in a compartment or behind a panel.
* Under the rear floor: Less common, but possible.
To find it, you'll need to:
1. Check the owner's manual: This is your best bet if you have it.
2. Visually inspect the van: Look closely under seats, in cabinets, and in the rear cargo area for vents, grills, or access panels that might lead to a blower motor.
3. Listen for the sound of a blower motor: Turn the rear blower on (if it works) and listen carefully to try and pinpoint its location.
Without knowing the specific conversion van manufacturer and model, it's impossible to give a more precise answer.