Suggestions needed to feed a rigid tube liner above the roof with a flat concrete top.

[begreen]

A $20, 30cm table fan as earlier suggested would move a lot more air and if it didn't make a difference it would still be useful.

 

[yonny33]

A $20, 30cm table fan as earlier suggested would move a lot more air and if it didn't make a difference it would still be useful.

Yes, I realize that but I want something discrete and unobtrusive.

A small efficient fan in the wall is ideal.

 

[begreen]

The table fan is for testing and will move a much larger volume of air. Those little bath fans are for small rooms and move a small amount of air.

 

[yonny33]

The table fan is for testing and will move a much larger volume of air. Those little bath fans are for small rooms and move a small amount of air.

The fan will replace the air about 3+ times an hour according to my calculations. Leaving it on from about 11am to 11pm. Slow but steady.

We'll see when the colder weather comes.
Room used to dip to about 16-17c during the coldest weeks.

Update: The wife is definitely happy - she has noticed a change in the feeling of the room and has approved. That's a thumbs up. Will select a slightly larger fan with a 125mm duct instead of 120. 30% more blowing power.
11w fan that blows 210m3 per hour.

 

[yonny33]

Rubbish!!
The new fan that has a higher output (rated at 33db) compared to the smaller one at 32db is MUCH louder. Too loud.
The sound rating is way off. 33db at what distance? 5 meters perhaps. 88 USD also! Not happy.

So I've installed it the other way so the noisier part is inside the bedroom blowing the cold air out. With a grill on the other side, it is much quieter. I bought this one as it had a nice glass front also for the visible part down the stairs. What a waste.

Oh well too late now.