Two 4 inch extractors through one 6 inch hole

[morbidmonkey182]

Hi fellow growers,
I have a question on extracting and without going through rather complicated equatios (which I admittidly have absolutely no idea how to perform) I was hoping someone could give me an answer for.

 

I have two tents that I want to extract through one hole. They both run 4 inch extractor fans and I'm hoping to vent through one 6 inch hole in the ceiling. My plan is to expand each 4 inch fan to 6 inch ducting directly at the output of the fans and then connect both of the 6 inch ducts to a Y splitter ducting piece before going through the hole in the ceiling. I would also fit a back draught shutter to each duct immediately before the Y splitter. My question is would this put too much strain on the 4 inch extractor fans and burn them out or should they be able handle it? My common sense tells me they should join to 8 inch ducting but this isn't really an option for me with 6 inch being the maximum I could stretch to. Any help or advice would be greatly appreciated.
Cheers

 

Morbidmonkey

[ratdog]

if you have fan controllers then you should be ok i would think

[monkeypig]

2x4 inch holes have an area of about 25 inch squared,

1x6 inch hole has an area of about 28 inches square.  You'll be fine. The only thing to aim for is an equal run in both ducts to keep it as balanced as possible.

[morbidmonkey182]

Nice one thanks for the replies I'll give it a go (and report back if things go to shit ) 

 

Cheers