In my first picture I show you the roof as I purchased my FWC camper. With the rear in the foreground, the first smoke colored vent cover is over my sink/cooking area.
The problem was that it was only a passive vent without a fan. The second smoke colored cover further towards the front came as a power vent with reversing fan to push out and pull in over the double bed.
Having the powered vent over the bed was not convenient, as I cool in the back and I often sleep on the lower bed and not lift the roof. With the roof down the fron vent is blocked for usage as it is smothered in bedcovers. I quickly realized that I needed a powered vent in the rear over my cooking / sink area for my upcoming 2018 Travels.
In order to move forward, I first needed to determine if I needed to replace the whole vent or attempt an upgrade to a power vent.
Atwood Mobile Products makes the Fantastic Vent so I called them and I was told I could upgrade and leave the roof and vent cover in place. They told me the model number to order after I told them that I wanted a reversing vent like my other vent, but also wanted a temperature controlled switch. They have one with the rain sensor on the cover to detect moisture and close automatically, but I didn't feel I had the need for that option.
I ordered the kit I needed from them on Amazon and found some quiet time to dedicate my efforts on the upgrade. Luckily the FWC was in my garage during the summer as the directions didn't work exactly as the directions indicate. It assumes you have a lid switch to sense that the cover of vent is open enough for fan to operate and you don't figure this out until you start wiring everything half assembled.
I was going to call Atwood back for the information and complain about the upgrade not having the part, but decided to search and find the switch on Amazon and ordered it from Atwood though Amazo.
In the end it assembled correctly, except that they supplied another roof cover lifter That I couldn't figure out why and I left the lifter that was on the vent as it originally came.
Here is the extra feature I got that isn't in the one over the bed. This knob allows you to set the temperature that the fan turns on at. A few degrees below this setting the fan shuts off.
I find this auto feature great for cooking and as it warms up I figure it will help exhaust heat in the camper to keep the temperature at a good level to run the Engel more efficiently.