1. Popular Modification in the USA
The changeout of the bathroom vent for a Fantastic Vent or Fan is a popular modification in the USA. There are various options for the dome, including a very flat lid. It seems many people choose a clear or tinted dome but I went with the solid white flat lid--it's is lower height and keeps sun out.
In the USA, we had to purchase a European size 16" x 16" (400 x 400) Fantastic Fan to fit. Standard size in the USA is 14" x 14".
There are some owners in the Pacific Northwest USA (mild cloudy climate) who skip the modification as unnecessary in their climate.
https://sprinter-source.com/forums/inde ... ost-834222
2. MaxxAir Substitute
Other owners have gone with the MaxxAir fan instead of the bathroom vent. The main advantage of the MaxxAir has a built-in hood cover so the fan can be left open even when raining (and also, don't have to worry about direct sun). The MaxxAir hood is longer than a Fantastic Fan and extends over the back of the van.
https://sprinter-source.com/forums/inde ... ost-583131
3. OneManVan Modification
OneManVan in the USA took an Endless Breeze fan and mounted it inside the bathroom vent. It is removable. Thus, he retains the original bathroom vent and adds a removable, also flipdown, fan.
https://sprinter-source.com/forums/inde ... ost-678796
https://sprinter-source.com/forums/inde ... ost-454602
4. Bathroom Door and Other Ventilation
There are various ways to keep the bathroom door open for maximum ventilation, including hooks, magnetic doorstops, etc.
AutoCamp also has a small hook which goes between the door handle latch and one of the metal hooks in the frame. This keeps the bathroom door slightly ajar rather than fully open.
http://eat-drink-men-women.blogspot.com ... l?m=1#more
In the USA, our version has an air conditioner with vents. By opening the compartment door above the bathroom door, air flows from inside the bathroom to the rest of the van.
Folks will open the slide wing vents for ventilation back to the Fantastic Fan.
https://sprinter-source.com/forums/inde ... ost-390481
https://sprinter-source.com/forums/inde ... ads/39151/
5. Modification Idea
There is another idea for mounting a fan inside the large Heki skylight. Some non-Westy owners have done something like that using eyehooks and a fan.
https://sprinter-source.com/forums/inde ... ost-620963
6. USA Kitchen Fan
The USA version has an air conditioner. One person has removed the air conditioner and cut a hole in the kitchen area ceiling for a fan. Look for Westy #248.
All of the above can be searched at:
https://sprinter-source.com/forums/index.php?forums/68/