Doran L-1212 Light Tight Darkroom Louver for A-1212 Fans

This is a Louver for A-1212 Fans, it is not the fan itself. Unfortunately we no longer have the A-1212 fan. If you are looking for a fan we have the Doran Pro-lab SL/WC Darkroom Exhaust Fan with Wall Cap as a special order item linked here. https://bhpho.to/3iWCUsa. This can be installed into a slanted ceiling, space permitting.

This louver can be mounted on a slanted roof if the A-1212 fan is mounted in the same manner.

This is just the louver. Think of it as being like a grille that blocks light. There is no fan. Rather, it goes with A-1212 fans.

13.75 x 13.75" (WxH) (outside grill) Cut out size is 12.25 x 12.25" (back of grill is 1.25" deep)

Doran L-1212 Light Tight Darkroom Louver for A-1212 Fans is not a fan, It is the cover for the discontinued Doran Light Tight Darkroom Exhaust Fan A-1212.

No. It works as you would expect. Cut the hole - screw in the vent. Done!

it's just a louvre, not a fan. No rating.

In my application, Im moving ambient air thru a light tight black box of about 64 cubic feet. I have three of the darkroom louvers in the door. I push air into the box with a variable speed fan thru a HEPA filter. With the fan on its lowest setting, I needed three lovers to keep enough air exiting the box, so as not to blowup the box. Sorry, cant tell you the CFM of the fan, but as I mentioned, its variable speed and low speed is low. I mention this to point out that the louver itself blocks a fair amount of air flow. If youre trying to keep dust out, of an area, then your exhaust fan should never be turned off, and air entering the room should be filtered. If your exhaust fan is for fumes, then it needs to be on 24/7 or dirty air could re-enter thru the fan when its turned off, if the fan discharge does not have self or manual closing louvers (kind of like a dryer vent). If the exhaust fan is just for drawing heat out of the room (and you still want to control dust), then remove the fan seal as many room openings as possible and use two fans with HEPA filters (one for intake, the other for exhaust). Most HEPA filters by default are light tight, but will most likely cost more than the L-12152. Understand however that you will now be relying on the ambient air outside the dark room for heating and cooling, unless you have other provisions.