Kitchen chimney hood/extractor

[Bunkermagnet]

So took @Neilds advice and popped out the screws and lo and behold the flex hose from the flat roof has completely detached from the extractor motor. It was held there by duct tape.


View attachment 55171

So i have now secured it with a metal hose connector. Now the air is no longer coming thru the side vents.


However, got on the flat roof and ther is only a little air coming out thru the pipe. Now i am even more worried. I am assuming there is a block somewhere or one of the builders probably put something into the pipe ..

That is adventure for tomorrow

Duck tape is often used to secure a flexi hose to the hood coupling, however you need to use enough of it.
Looking at your picture, I can only see half of the butterfly valve. Thats the 2 flaps that are spring loaded that are pushed open by the air being pushed up, and close when the hood stops. They aren't neccessary and they do provide a little resistance of air, but when it's cold they do stop the air getting back down into the kitchen and also stop noise funnelling.
How long is the hose, and how far is the exit point?
What you have said suggests that either the butterfly valve is sticking, the half I can see has jammed somewhere , the hose is way too long or the hose is kinked.
It would have been a good idea to have run the hood wihtout the hose connected so you know the hood is pushing good air flow firsy.

 

[Mudball]

Duck tape is often used to secure a flexi hose to the hood coupling, however you need to use enough of it.
Looking at your picture, I can only see half of the butterfly valve. Thats the 2 flaps that are spring loaded that are pushed open by the air being pushed up, and close when the hood stops. They aren't neccessary and they do provide a little resistance of air, but when it's cold they do stop the air getting back down into the kitchen and also stop noise funnelling.
How long is the hose, and how far is the exit point?
What you have said suggests that either the butterfly valve is sticking, the half I can see has jammed somewhere , the hose is way too long or the hose is kinked.
It would have been a good idea to have run the hood wihtout the hose connected so you know the hood is pushing good air flow firsy.

When i opned it, and ran without the flexi... the RHS of the butterfly was flapping like a hummingbird. The left was a bit slower, would start moving when i ramp up the speed. I suspect a kink or somehting else. The external unit was installed during building work and it is about 500 cm to the right of the actual hood. (kitchen was designed later). So they had to extend it using the flexi. Additionally the outside venting unit was 200 or 250mm. So they had to then put a coupler to get it from 200 to 150... All this is hidden under a bulk head with no access. i fear that we may have to break into the bulkhead to figure this out. More costs

 

[Neilds]

So took @Neilds advice and popped out the screws and lo and behold the flex hose from the flat roof has completely detached from the extractor motor. It was held there by duct tape.


View attachment 55171

So i have now secured it with a metal hose connector. Now the air is no longer coming thru the side vents.


However, got on the flat roof and ther is only a little air coming out thru the pipe. Now i am even more worried. I am assuming there is a block somewhere or one of the builders probably put something into the pipe ..

That is adventure for tomorrow

Would like to take credit but wasn’t me

 

[Mudball]

Duck tape is often used to secure a flexi hose to the hood coupling, however you need to use enough of it.
Looking at your picture, I can only see half of the butterfly valve. Thats the 2 flaps that are spring loaded that are pushed open by the air being pushed up, and close when the hood stops. They aren't neccessary and they do provide a little resistance of air, but when it's cold they do stop the air getting back down into the kitchen and also stop noise funnelling.
How long is the hose, and how far is the exit point?
What you have said suggests that either the butterfly valve is sticking, the half I can see has jammed somewhere , the hose is way too long or the hose is kinked.
It would have been a good idea to have run the hood wihtout the hose connected so you know the hood is pushing good air flow firsy.

Got on the Flat roof and we have this.. popped the screws on the side, but the black top won’t come off.. it does seem to go in a circle

 

[Bunkermagnet]

Got on the Flat roof and we have this.. popped the screws on the side, but the black top won’t come off.. it does seem to go in a circle

Firstly, the butterfly flaps should open freely even on the lowest fan speed setting. I'm not into roofing and ducting, but that looks like a pop up cover that should be pushed up when the fan blows, and if it is there is no need for the butterfly flaps.
Reducing the hood ducting diameter will cause baffling of the blown air, so more noise and less performance.

 

[Mudball]

Firstly, the butterfly flaps should open freely even on the lowest fan speed setting. I'm not into roofing and ducting, but that looks like a pop up cover that should be pushed up when the fan blows, and if it is there is no need for the butterfly flaps.
Reducing the hood ducting diameter will cause baffling of the blown air, so more noise and less performance.

While the situation has improved considerably since i put the metal hose connector. I thik it was not very effective. So did a few tests today and there is plenty of white smoke that escapes from the side while some go thru. So i repeated the same test without the filter. Same thing, but at the same time I can feel a very strong down draft from the extractor. Is this normal?
My assumption is that there is possibly a block somewhere in the flexipipe. Some air goes out, but it is blocking a good chunk. the pressure inside the tube might have been strong enough to rip the duct tape in the first instance. Now since I put the metal ring, it is forcing it down via one of the butterfly flaps. The big challenge we have is that the flexi is enclosed inside a bulkhead and there is no access. So either demolish the flexi or do some endoscopy from the roof.

 

[ADB]

We are in the process of ordering a new kitchen. I've never really seen the point of the recirculating systems.....I know they work a bit, but if possible I'd really like the extractor to extract the smelly and a bit greasy air to the outside. My wife is trying to decide whether to leave the sink as in the picture or move it over by the washing machine. A wall is coming out where the breakfast chairs are located. A little concerned that the drain on the sink has to go all the way over to where the washing machine is and we are thinking that having the washing machine/dish washer/sink might just work better if it was all over on that side.
View attachment 55165

I probably wouldn’t have the sink/drainer where people are sitting and eating at the breakfast bar.

 

[Fade and Die]

While the situation has improved considerably since i put the metal hose connector. I thik it was not very effective. So did a few tests today and there is plenty of white smoke that escapes from the side while some go thru. So i repeated the same test without the filter. Same thing, but at the same time I can feel a very strong down draft from the extractor. Is this normal?
My assumption is that there is possibly a block somewhere in the flexipipe. Some air goes out, but it is blocking a good chunk. the pressure inside the tube might have been strong enough to rip the duct tape in the first instance. Now since I put the metal ring, it is forcing it down via one of the butterfly flaps. The big challenge we have is that the flexi is enclosed inside a bulkhead and there is no access. So either demolish the flexi or do some endoscopy from the roof.

Does the roof vent allow enough air flow? Maybe remove the mushroom thing and see if it improves matters?

 

[Mudball]

Does the roof vent allow enough air flow? Maybe remove the mushroom thing and see if it improves matters?

i did.. and you can feel somethings come thru.. but nothing as strong as i was expecting. From the top you cant see any blockage.. but the pipe bends at the bottom

 

[Fade and Die]

i did.. and you can feel somethings come thru.. but nothing as strong as i was expecting. From the top you cant see any blockage.. but the pipe bends at the bottom

View attachment 55225

View attachment 55224

Yes, flexible pipe, especially the thinner stuff is a real killer for extractors. I used to have a document (which I cannot be arsed to find) that showed the % of extraction lost on each bend. From the inside, can you pull the flexi down to try to take out any excess that might be stuffed up there?

 

[Bunkermagnet]

While the situation has improved considerably since i put the metal hose connector. I thik it was not very effective. So did a few tests today and there is plenty of white smoke that escapes from the side while some go thru. So i repeated the same test without the filter. Same thing, but at the same time I can feel a very strong down draft from the extractor. Is this normal?
My assumption is that there is possibly a block somewhere in the flexipipe. Some air goes out, but it is blocking a good chunk. the pressure inside the tube might have been strong enough to rip the duct tape in the first instance. Now since I put the metal ring, it is forcing it down via one of the butterfly flaps. The big challenge we have is that the flexi is enclosed inside a bulkhead and there is no access. So either demolish the flexi or do some endoscopy from the roof.

The grills you talk about on the cowling, are the recirculation grills for when the hood is reciruclated. If you hood is ducted out, there should be no blow back or air escaping. It sounds to me like your exhaust hose is split somewhere or posisbly kinked.
Out of curiousity, have you try the hood with the cap off the exterior exit point?

 

[Mandofred]

I probably wouldn’t have the sink/drainer where people are sitting and eating at the breakfast bar.

Already corrected. Never was planning on having people actually sitting at the breakfast bar....but the sink is heading way over to the other side. My wife is now fixating on whether to have the peninsula normal width or mega width.

 

[Mudball]

Already corrected. Never was planning on having people actually sitting at the breakfast bar....but the sink is heading way over to the other side. My wife is now fixating on whether to have the peninsula normal width or mega width.

Your wife is right... that sink was in the wrong place. From my little experience, the bigger anything is, the better it is. It depends on the rest of the room and how much space you have. A friend of our has a peninsula. He has converted it into his bar counter

 

[chellie]

Already corrected. Never was planning on having people actually sitting at the breakfast bar....but the sink is heading way over to the other side. My wife is now fixating on whether to have the peninsula normal width or mega width.

It's good to have cupboards underneath but have an overhang that you can sit at. Hope that makes sense.

 

[Mudball]

The grills you talk about on the cowling, are the recirculation grills for when the hood is reciruclated. If you hood is ducted out, there should be no blow back or air escaping. It sounds to me like your exhaust hose is split somewhere or posisbly kinked.
Out of curiousity, have you try the hood with the cap off the exterior exit point?

Yes.. when i was on the roof, you could barely feel the air coming out of the stack (you could see some white smoke). So had to remove the mushroom cap to look in. And then i could atleast see some of the white smoke. So if there is a kink/block it is after the bend.
Spoke to the builder today, and he says that they had left a fair bit of flexi pipe and maybe the kitchen fittters did not pull enuf.

 

[Mudball]

It's good to have cupboards underneath but have an overhang that you can sit at. Hope that makes sense.

Add a pole and you can find a dancer somewhere

 

[Tashyboy]

Just outta interest, and I don’t know the answer to this. How high does the extractor go vertical. Is the fan strong enough.

 

[Mudball]

Just outta interest, and I don’t know the answer to this. How high does the extractor go vertical. Is the fan strong enough.

I think it is supposed to be good. I had never heard of Westin brand before. It is 90cm wide and as per the manual its Airflow rate is 800 CMPH... Supposed to be fairly strong. (happy to be corrected, but hoping not to be)

 

[Bunkermagnet]

I think it is supposed to be good. I had never heard of Westin brand before. It is 90cm wide and as per the manual its Airflow rate is 800 CMPH... Supposed to be fairly strong. (happy to be corrected, but hoping not to be)

Westin are a British company. Their hoods are very good....and expensive.

 

[larmen]

You can get a cheap endoscope from Amazon. Maybe it’s worth a shot?