On 28/04/18 19:07, GB wrote:
On 28/04/2018 17:46, The Natural Philosopher wrote:
On 28/04/18 17:44, Raleigh wrote:
new half bath on first floor above basement ,interior wall next to
chimney.
Toilet and small sink. Only time the fan would be used is toÂ* remove
noxious
smell from doing #2. Air ventÂ* would be 5 inches from chimney. Old
oil furnace
port capped on chimney 30 years ago in basement 5 feet under new half
bath.
Can I vent into chimney.

yes

The snag is that in many years time somebody may reconnect a boiler to
the chimney, and somebody taking a bath will get poisoned. That's not
likely in the foreseeable future, but after the house has changed hands
a couple of times ....


2 thoughts:

1) Any boiler installer would line the chimney as standard;

2) The *real* purpose of a bathroom fan is to keep humidity and damp
under control which means it will be dumping a lot of warm most air into
a cold chimney which will condense before it gets anywhere.

I would advise against it unless the OP sticks ducting in the chimney
with a properly drained condensate trap at the lowest point.