Slam vents - Use for ventilation?

Sniggib

Member
Hi all,

So I have had an idea of using my slam vents to ventilate the rear of my can which will be a garage / kit store.I've managed to get a piece of hosepipe through the vent. I then plan on attaching a 12v fan and running this to extract air to help dry kit. The idea being that the negative pressure from the fan will draw a small amount of warm air from the main living area.

Can anyone see an issue with this? In particular for allowing exhaust fumes into the van via the tube, or moisture in.

Thanks.IMG_20201228_112442.jpgIMG_20201228_112442.jpg

IMG_20201228_112417.jpg
 
My thoughts are that given the existing slam vents shouldn't let air back into the van then the tube shouldn't be a problem. Assuming I put the fan to extract outside then my thinks Ng is that this is no different to the existing situation.

Cheers
 
My question would be where is the new air coming from? Are the slam vents not there as a one way valve to allow a change in pressure to escape when you close the door and not smash the windows. If that's the case then would you need a source of fresh air to circulate from the other vent?
 
Thanks @Kev_

So my thoughts are that we will leave the front windows / side windows open and then the air will be drawn through the van and out the slam vents.

Writing that, I'm wondering if the Dan will draw air in through the slam vent, then back out through the tube on the slam vent as it would be the path of least resistance rather than drawing air through the van.
 
Having stuck my hand in to find the vent, there is a thin membrane which appears to be intended to close as a one way valve, but it just stays open all of the time so not much of a valve really.
 
I think it is supposed to stay open, then close when the outside pressure is greater, when the vehicle is moving or the wind blows at it. You want the air in the vehicle to get out, but not let outside air back in.
 
I think you’ll find that the bore of the hose is far too restrictive. There will too much loss to allow any significant airflow.
The only way this hose would work would be with a positive displacement pump / compressor.
If you used a forced draught fan to raise the pressure of the garage it would vent through the slam vents providing they were not blocked with carpet lining. In this case the required fan would be large, noisy and consume a significant amount of power.
It might be better to heat the space and vent through convection via a roof vent.
 
Thanks @DXX trying to avoid a roof vent really but whilst gaining a small amount of ventilation.

My original plan was just to draw a small amount of air into the garage via fans on the 'bulkhead' and then it would vent via the slam vents naturally. However, then I noticed I could get a tube through so thought that might be better than just the natural venting.

I don't mind if there is limited air flow, just a small amount to keep a little air flow to allow drying of kit.

Thanks for the info

Cheers
 
Thanks @DXX trying to avoid a roof vent really but whilst gaining a small amount of ventilation.

My original plan was just to draw a small amount of air into the garage via fans on the 'bulkhead' and then it would vent via the slam vents naturally. However, then I noticed I could get a tube through so thought that might be better than just the natural venting.

I don't mind if there is limited air flow, just a small amount to keep a little air flow to allow drying of kit.

Thanks for the info

Cheers

Could you not consider installing a drop vent in the floor say, behind the jack mount? I don't know the practicalities of landmarks etc but if possible you could have the vent open or make a cover when not required. Positive pressure should keep the air moving one way but in a standing traffic situation, you'd have to be aware of potential exhaust fumes recirculating.

20201230_000521.jpg
 
Back
Top