We have a home that has a gas firplace in the basement and a wood
burning fireplace on the upper floor. When we start a fire in the
upper fp we smell smoke downstairs. There's no damper on the gas one
downstairs. The gas one has a pipe that goes up the brick work to the
outside. We noticed this smell got worse after we installed a chimney
cap for the wood fp. So does some of the smoke go down the pipe of our
basement gas fp? If that's the case what can we do to prevent this?

Thanks
JaKe
Seattle