Fit external chimney fan to aid extraction over a gas range cooker

graburko

Hi there, would appreciate some feedback on this particular conundrum.

We bought an old cottage that had been renovated some years previously. The cottage had a large 120cm semi-industrial all-gas range cooker fitted into the fireplace. The chimney appears to be flue-lined and has an adequate down draft as the only ventilation. There is/was no extractor fitted. We have lived with this arrangement for 3 years.

We have just bought a new range of similar size that is duel fuel. Have had the gas fitted by an RGI technician and certified and waiting on an electrician to finish the install.

We are now trying to figure out if we can fit an extractor over the new cooker inside the chimney breast, however the space itself is very cramped so any slimline recirculating/carbon filter extractor I can find online would not fit, and any eternal extractor vent up a chimney would not be sufficient/effective given the vertical height of the flue. And even if we did find something that could work, the clearance above the gas hobs would only be 450 mm, well below the minimum recommended 750 mm. No option to vent horizontally, given the thickness of the stone chimney breast and the location in the middle of the house.

The question I have is considering all the limitations of the space, and the only alternative I could see being that we stay with the status quo of the gas hob venting naturally up an open chimney flue, would it be an option to fit an external chimney fan outside, designed to improve ventilation for a wood burning stove to act as a booster to ventilation of the gas hobs?

Thanks in advance.