Gene Cafe - Duct reducer for large chaff collector

Duct Reducer 100mm-80mm for Large Chaff Collector

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If you have purchased the large chaff collector for the Gene, this article will be of particular interest. The outlet vent pipe is approx 80mm diameter but the commonly available and cheapest flexible ducting is the standard 100mm diameter Corrugated Aluminium ducting available from Wickes for £4.99.


You can get 80mm diameter ducting, but it tends to be twice the price and has the potential to restrict overall airflow. The 100mm ducting does allow some leakage of smoke around the area where it is placed over the chaff collector, especially if the wind puffs the wrong way outside.

There is a 100mm to 80mm taper (duct reducer) connector available from an e-bay seller called 1st-4-Vent for around £3.58 plus postage.


This fits perfectly on the output vent of the large chaff collector and as shown in the photos (Click to enlarge) makes a particularly neat installation. It also means the amount of roasting smoke in the house is kept to an absolute minimum and it purely limited to those faint wisps that escape from where the chamber fits into the gene. Even roasting in the Garage my clothes and hair used to smell of smoke, but not after this adaptor was fitted!

Many thanks to monsoonblade on our forum for posting about this very neat solution and the e-bay seller.

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