Charcoal Filter

[biot]

I have just changed my cooker hood for a like for like swap. The model is fitted with grease and charcoal filters. I have drilled the wall and placed a plastic duct though connecting it to the space where the blacking plate was.

My duct goes into the garage and I wish to run flat channel to the garage exit and then into a vent (similar to a tumbler dryer flap).

Do I need the charcoal filter in if I am extracting and is there any problems with the ducting length outside

Further to this the intructions supplied by comet did not say anything just a diagram of where to drill a hole.

Thanks

Robert

 

[tim west]

Unless you want the fat and grease collecting and congealing inside the duct causing bad odours i'd leave the filters in.

 

[biot]

Thanks for the prompt reply tim, I was asking merely as i cooked some food this evening and the smoke was not extracting as i would like. I was wondering if despite my external duct the charcoal filter was in some way causing air to recirculate. theoretically however and applying the same analogy as for water, I presume the air is sucked through the grease filter and then the charcoal filter and then pushed to the backing plate which if blocked recirculates the vapour or if vented outside, discharges to atmosphere.

The only other problem i can see is the motor is not powerful enough to extract efficiently

 

[tim west]

Are you sure the grease filters not blocked?

 

[Steve]

I'd take the filters out. Simply because they reduce airflow.

 

[biot]

Thanks for replies. No the unit is not blocked and is brand new. I did a test last night with a pan of boiling water on the hob and the extracter on with and without the filter. Without the filter i had a better extraction airflow. For the purpose of the test however i broke the flat channelling in the garage at the wall duct point to test it. I am thinking that in the colder damp climate we are having of late the 3 meter plastic channel could act as a condensor as opposed to a vent to atmosphere.

 

[bernardgreen]

Having a filter filled with inflamable fat over the hobs could be considered a fire hazard if cooking au flambe ( or something catches fire ).

So I would remove the filters. And provide a means to remove and clean the long length of ducting where steam condenses and grease settles.

 

[tim west]

The problem with your setup is that a cooker hood as you have installed is not suitable for ducting out, the unit is not sealed adequately in order to "push" the volume of air that distance along the duct.

For what you want, you need a purpose made "extractor" rather than a domestic cooker hood arrangement.