Cool air falls toward the floor. Deflectors shouldn't be necessary unless the vent is behind a curtain or something, or if you want to deflect the cool air toward your easy chair.
Yes. You need to open the plumb, & you have an air vent there.
like deflectors on lorries
No. You vent air from a sewer line.
some lorries have deflectors fitted over their cabs, so it becomes more streamline, it can DEFLECT the air resistance too :) The Ugly Rat
Deflectors should typically be facing down when the heat is on to direct warm air flow towards the floor area, helping to distribute heat more evenly in the room.
To reduce the air resistance/drag acting against them and also to reduce the fuel consumption.
You can install a vent fan to push the air to an exterior wall. Another option is to use a ventless dryer that does not require an external vent.
An air admittance vent is a mechanical sewer vent which allows air to enter into the sewage system but does not allow exhaust of sewer gases.
read your owners manual. i had to also. there is only two vent settings that will not use the compressor. the vent setting with the upper and lower vent showing will use the compressor.
the air vent is cold
An air vent is an opening, sometimes covered by a grate, which allows air to circulate around a room.