Hi all you genius plumbers! Thanks for all the help you've given me in the past and give to everyone every day, truly a wonderful resource!!

I live in a second story 'apartment' above a first floor garage. I have the upstairs ceiling removed because i'm changing from flat to cathedral. it got really hot yesterday, so I put fans next to the gable attic vent and a roof turbine vent to pull the hot air out of the attic.

soon after i did that i started smelling sewer gas downstairs near my bathroom(utility sink and toilet only).
it seems to be coming out of a quick vent next to the utility sink. it's one of the cheap ones not the expensive studer vent.
I'm sure there are no dry traps for it to be coming from and it does't seem to be coming from the toilet.

does a negative interior pressure logically cause a quick vent to reverse direction? I thought it would be uni-directional ventilation? would a studer vent prevent that problem? how could i eliminate the negative pressure due to the attic fans? i guess i could crack a downstarirs window a little bit even tho i have the AC running part of the time... any thoughts? thanks in advcance

a more negative pressure in the house would make the vent seal better.
probably just plain defective and needs replacement.

thanks Packy,
you think that's common with the cheapo lowe's/home depot quick vent?

those stores don't make any of their own products. they buy the product that gives them the most profit irregardless of quality issues..

so true Packy, however i'm considering another possibility, potential installer error(me). I may not have screwed them in tight enough; thinking, as i did at the time, that leaks werent' an issue i just put them in hand tight. when i went to remove they weren't hard to unscrew so i'm reapplying dope and tightening hard hand tight(since they're just plastic). if smell goes away after a while then im the big dummy!!! possibly the negative pressure was enough to draw some molecules past the teflon tape? (changed from tape to dope this time)