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Pin Head
9th Feb 2016, 01:09
Hi

Please can you advise the journey path of air in pulled by recirc fans. It pulls air from the floor grills and the the forward cargo compartment and then via the HEPA filters to the fan and then into the mix manifold?

Bit confused.

Many thanks

Pin.

de facto
9th Feb 2016, 04:48
The right recirc fan recirculates cabin air,the left recirculates air from the air conditionning bay.
Left is located back of fwd cargo,right fan on top of fwd cargo.
Fwd cargo is air tight,no air goes into it,or at least not supposed too...you wouldnt want a continous oxygen air source for it now would you?
The air that is going around the fwd cargo(for conductive heating)is air pulled by the exhaust fan,(cockpit air/eebay).
So recirc fans air is air recirculated air from Air con bay and cabin tonyhe mix manifold and then end their journey via the tube' ass ,the outflow valve that is.
Clear?

NSEU
9th Feb 2016, 05:05
What part confuses you? You've described it well

The recirc fan(s) is(are) under the cabin floor (actually just behind the rear wall of the forward cargo).

The stale air from the cabin (exiting via the floor grilles) and generally cool air in the cargo sidewalls is drawn through the underfloor hepa filter (s), then to the recirc fan(s). Ducts leading from the fan(s) go up the main cabin sidewall to the overhead cabin distribution ducts. The air is then distributed in the cabin via vents near the overhead luggage compartments and aircraft centreline.

A picture is worth a thousand words. Perhaps someone can provide a schematic diagram from the Maintenance Manual (21-25-00)

Cheers

Pin Head
9th Feb 2016, 06:09
Thanks.

I agree re picture - but I have no manual.

Any chance please of showing me it.

Jet II
10th Feb 2016, 13:41
Does this help?




http://i97.photobucket.com/albums/l212/sids666/21-4.jpg