I installed a General Aire Model 1042L Humidifier 4 years ago with the
bypass 6 in duct installed in the return air duct. I was just
wondering the effect of having the bypass line in the return air on
the air filter which is downstream of the bypass.

Questions: - 1. Will the moist air drawn through the air filter not
affect the operation of the filter?
- 2. Will the moisture be retained by the filter?

The reason why I when this route is that my heater supply duct is very
narrow about 5 in (which is too narrow for the 6in bypass line). The
duct is 5 in high by 20 in wide.

Thanks.