Having a kitchen extension built with downdraft induction hob on island (Elica Switch model), which ducts out the building. The spec of the duct should be 6" round or equivalent rectangular ducting. I was told by Elica this must not be reduced in size. The builder was given this information and kindly sourced some ducting and installed it at build stage. The duct runs in between the concrete slab and wooden floor and out the side of the house. The floor structure was sort of designed to accommodate this. The duct run is around 5m in total with 2x 90 degree bends.
The extension is now built with kitchen install almost complete and it's been brought to my attention that the rectangular duct used is smaller than spec. It's 200x60 (5" equivalent), but should be 220x90. According to data I've found online, it seems the flow rate is around 25-30% less in the smaller duct. The builder has apologised for the error but said it's too late to do anything at this stage. Note: There was nothing on the drawings about this, it was an "extra". What should I do? Should I push for the duct to be removed and replaced with the correct size? This would cause significant disruption including partial rip out of the new kitchen, etc. Or should I just live with it?
The hob was only just connected up yesterday and I'm not that impressed with the extraction performance to be honest. I tested it with a small pot of simmering water. The extractor had to be switched to one of the highest 2 settings in order to pull all the steam downwards. Set it to any of the slower settings (1-7) and some of the steam floats up to the windows on the ceiling. The "automatic extraction" setting on the hob seems ineffective too. This is supposed to monitor the hob settings and use readings from an air sensor to adjust the extraction rate. It simply doesn't pull enough on this setting.
Extraction was an important element of the design for us. There is a glass roof lantern directly above the hob and no opening windows nearby, so we wanted the downdraft to be as effective as possible. We purposely chose a hob with a high extraction rate.
Builder is a great guy and I don't want to fall out with anyone over this, however I'm feeling very disappointed at this stage and don't know where to go with this....
For the record, the kitchen fitter (independent from the builder) thinks the ducting with be sufficient.
The extension is now built with kitchen install almost complete and it's been brought to my attention that the rectangular duct used is smaller than spec. It's 200x60 (5" equivalent), but should be 220x90. According to data I've found online, it seems the flow rate is around 25-30% less in the smaller duct. The builder has apologised for the error but said it's too late to do anything at this stage. Note: There was nothing on the drawings about this, it was an "extra". What should I do? Should I push for the duct to be removed and replaced with the correct size? This would cause significant disruption including partial rip out of the new kitchen, etc. Or should I just live with it?
The hob was only just connected up yesterday and I'm not that impressed with the extraction performance to be honest. I tested it with a small pot of simmering water. The extractor had to be switched to one of the highest 2 settings in order to pull all the steam downwards. Set it to any of the slower settings (1-7) and some of the steam floats up to the windows on the ceiling. The "automatic extraction" setting on the hob seems ineffective too. This is supposed to monitor the hob settings and use readings from an air sensor to adjust the extraction rate. It simply doesn't pull enough on this setting.
Extraction was an important element of the design for us. There is a glass roof lantern directly above the hob and no opening windows nearby, so we wanted the downdraft to be as effective as possible. We purposely chose a hob with a high extraction rate.
Builder is a great guy and I don't want to fall out with anyone over this, however I'm feeling very disappointed at this stage and don't know where to go with this....
For the record, the kitchen fitter (independent from the builder) thinks the ducting with be sufficient.
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