Another one for a friend.
Just had a new kitchen fitted, but had "some problems" with the cooker hood - Siemens LC64GA520B. The manual isn't too descriptive about ducting, but does say :
"Round pipes
An inner diameter of 150 mm, but at least 120 mm, is recommended"
I read that as "at least 120mm, but 150mm is recommended.
First issue is that the fitter clearly decided that as the electrics are someone else's problem, he can ignore all electrical related things - so he boarded over the conduit put in specifically to get the supply cable to the hood and left the mains lead coiled up inside the duct cover (chimney ?) - he also boarded over the conduits put in for the under-cupboard lights Anyway, I managed to get an extra cable up the conduit in the wall and through the ceiling into the cover.
But he left the flexi ducting just sticking into the attic (it's a bungalow) - probably because he was given a kit that wasn't sufficient for the job. The kit was a Hafele 7215 125mm 1M hose kit - the box was left in one of the cupboards. My mate "mentioned this" to the supplying company and they came back - so now it's ducted to outside, but neither of us think it looks "right".
Firstly, there was a "large amount of duct tape" on the top of the appliance. I know from experience that this duct tape usually dries out and peels off - leaving nothing but the dried up glue behind.
To see what was there, we pulled the tape off, and found this
There's a reducer (I assume it's the one shown in the appliance instructions), and the duct is a very loose fit on it. Neither were fixed with anything but the tape.
The duct kit has an adapter with it, but this doesn't fit either the reducer or the appliance spigot
In the attic, there is now an extra length taped on
which goes through a hole in the wall to a terminal
For some reason, they've fitted a plastic sleeve in the wall which only goes about 2/3 of the way through (the hole isn't large enough for the outer bit), and the duct is clearly fixed to the grill with more tape.
I've suggested my mate ask the supplier about this, but he's got to the stage of not wanting them back. Anyway, down to some questions ...
Given that the manufacturer recommends 150mm duct, is 125mm sufficient. The hood does certainly suck with the 125mm, but would it be significantly different with 150mm ?
Is joining the duct with this duct tape acceptable ? Or what should be used ?
Would it be better done with rigid apart from the last bit down to the appliance (to make lining stuff up easy) ?
I'm thinking it would be better if the rigid duct went right through the wall, and was in fact the duct itself, so self supporting and the grill is just to "finish the hole" on the outside ?
Should we be concerned about condensation in the duct given that it's in an unheated roof space ?
My thoughts are to remove the grill, remove the piece of rigid duct, open the hole out and fit a longer section of 150mm rigid, and refit the grill (squarely on the wall this time !). Inside, use a 90˚ bend, another length of rigid duct, and finally a short section of flexi duct to the appliance.
Still, it's better than the old hood that got pulled out. We think it was a "BIY" job by the previous owner, but that just vented into the attic
Just had a new kitchen fitted, but had "some problems" with the cooker hood - Siemens LC64GA520B. The manual isn't too descriptive about ducting, but does say :
"Round pipes
An inner diameter of 150 mm, but at least 120 mm, is recommended"
I read that as "at least 120mm, but 150mm is recommended.
First issue is that the fitter clearly decided that as the electrics are someone else's problem, he can ignore all electrical related things - so he boarded over the conduit put in specifically to get the supply cable to the hood and left the mains lead coiled up inside the duct cover (chimney ?) - he also boarded over the conduits put in for the under-cupboard lights Anyway, I managed to get an extra cable up the conduit in the wall and through the ceiling into the cover.
But he left the flexi ducting just sticking into the attic (it's a bungalow) - probably because he was given a kit that wasn't sufficient for the job. The kit was a Hafele 7215 125mm 1M hose kit - the box was left in one of the cupboards. My mate "mentioned this" to the supplying company and they came back - so now it's ducted to outside, but neither of us think it looks "right".
Firstly, there was a "large amount of duct tape" on the top of the appliance. I know from experience that this duct tape usually dries out and peels off - leaving nothing but the dried up glue behind.
To see what was there, we pulled the tape off, and found this
There's a reducer (I assume it's the one shown in the appliance instructions), and the duct is a very loose fit on it. Neither were fixed with anything but the tape.
The duct kit has an adapter with it, but this doesn't fit either the reducer or the appliance spigot
In the attic, there is now an extra length taped on
which goes through a hole in the wall to a terminal
For some reason, they've fitted a plastic sleeve in the wall which only goes about 2/3 of the way through (the hole isn't large enough for the outer bit), and the duct is clearly fixed to the grill with more tape.
I've suggested my mate ask the supplier about this, but he's got to the stage of not wanting them back. Anyway, down to some questions ...
Given that the manufacturer recommends 150mm duct, is 125mm sufficient. The hood does certainly suck with the 125mm, but would it be significantly different with 150mm ?
Is joining the duct with this duct tape acceptable ? Or what should be used ?
Would it be better done with rigid apart from the last bit down to the appliance (to make lining stuff up easy) ?
I'm thinking it would be better if the rigid duct went right through the wall, and was in fact the duct itself, so self supporting and the grill is just to "finish the hole" on the outside ?
Should we be concerned about condensation in the duct given that it's in an unheated roof space ?
My thoughts are to remove the grill, remove the piece of rigid duct, open the hole out and fit a longer section of 150mm rigid, and refit the grill (squarely on the wall this time !). Inside, use a 90˚ bend, another length of rigid duct, and finally a short section of flexi duct to the appliance.
Still, it's better than the old hood that got pulled out. We think it was a "BIY" job by the previous owner, but that just vented into the attic