Hi, just wondering if anyone could help.
I live on the 3rd floor of a block of flats and I am having problems with my bathroom extractor fan. The owner of the flat below me has had a new fan fitted in her bathroom which is quite a powerful one and I am now getting air coming through my fan. My bathroom now gets slightly damp and small particles of dirt come through when she has her fan on. As we all share the same duct I was wondering if the was a fan I could have installed to solve this problem.
Your neighbor's new fan is strong enough to create back pressure in your portion of the vent it seems. The problem is the shared vent. That is a poor idea, because the static pressure in the vent will result in the air that's being moved exiting the vent via the path of least resistance (your fan).
Changing your fan probably won't do you any good unless you leave it running 24/7.
I would suggest finding a way to install your own vent (to outdoors) for your own fan and capping the old vent where it goes to your bathroom.
Why not get the apartment owners or whomever is responsible for maintenance to correct the problem. If you share an air way with others, it would make sense to install one fan on the roof. This way everyone has the same amount of air movement, providng all the ductwork is exact. Then you can stink it up 24 -7. Also, knowone has to furnish there own fan.
I know nothing about HVAC. Just seems like the right thing to do.