odor isuues

i have built a small little grow area within my house, its 1 metre by about 3.5 metres.
there's a 1 x 1 grow area on the right an enclosed cloning area on the left and enough room to swing a small cat in the middle where all the swearing/magic happens.
Before i enclosed this area it had an in-floor heating duct which i disconnected from the system.
I hooked up a medium canfan and a large carbon filter on the end of about 1.5 - 2 metres of ducting.
In the room there are 2 lengths of ducting coming from the floor vent up in a v shape that hang over the main grow area.
all this should suck out to under the house, through the filter and no one is the wiser.
BUT...., my house stinks!!
I'm thinking of lining the doorway in carbon fiber filters??
any ideas or tips??
oh yeah the doorway is inside a closet with the back knocked out but and replaced with a blackout curtain with a zipper in it

Like nobody is going to smell that from outside the house at ground level? Maybe not, I don't know, but one thing's for sure, "under the house" will soon be "the black mold outbreak under the house" and a little later it will be "under the condemned house I used to be able to live in". But wherever you vent it, to hide the smell you just put an open bottle of AirWick in front of the outlet, or somewhere in the duct system. People might say where's all that AirWick smell coming from but that'll be about all.

Hey Bob.
There's no smell outside the house or even under, just in!
there's about 4 foot clearance under there.
Why the mold? I've been going for a couple of years and haven't seen anything. I've slowly been increasing fan sizes and if i go any bigger it'll sound like I'm hiding a jet.

BouncinBob is it possible that your air is not been cleaned enough and the warm air going under the house is rising back into your house and making it smell? Maybe turn the fan speed down so the air is cleaned better. Plus check your ducting and fan/filter joins to make sure you don't have a leak. If you have a tear in your ducting you could be pulling smelly air through, or if your filter is cheap you could have gaps in the carbon. Cheap filters are sometimes not filled correctly, which is all it takes to allow air not to be cleaned.
If temps are already perfect so you cant turn fan down then get a bigger filter.

Also make sure your fan and filter are matched. If your filter is 600 cfm and the fan is 300 cfm or less it will not work. The mold issue will come from venting your hot humid air into an area that stays dark with exposed wood and earth. It may be a problem or may not. Depends on lots of factors. The added humidity will improve the chances of the mold though