Smoke from next doors fire

Joll

Hello, looking for any advice with regards to an issue with next doors fire.

We have a very old house which backs on to next doors property & have a shared chimney stack. They recently had a new fireplace, metal liner and anti downdraught cowl installed. We have not used our fire for well over a year, maybe 2.

The problem is that the last 2 weekends, our living room has been very smoky when they have lit their fire, however, they say they have lit the fire at the weekends for the last 8 weeks but we have only had the smoke problem for the last couple of weeks.

Having looked at the chimney pots could it be that their new cowl is causing the smoke to blow back down our chimney in certain wind/weather conditions, as the pots are very close together and the same height?

We immediately bought a carbon monoxide alarm which has not detected anything.

We have both lived here for 17 years and never had this problem before.

I would be very grateful for any advice.

Many thanks

SG27

Someone had an identical problem a few weeks back:
http://forums.moneysavingexpert.com/showthread.php?t=5344604