Ducting hot air waste into loft space.

[Progen]

I have a portable air conditioner which has an exhaust pipe to vent the hot air outside. The problem with this is that a window is needed to be open which causes the air conditioner to fight it's self, exspecialy in the summer months, as warm air blows back into the room.

So I was thinking, could the pipe be put through the ceiling and into the loft space and just release the hot air there?
This will have the advantage of no window open, so less noise and a lower electricity bill as the air con unit will have to operate less with no hot air coming back into the room.

The plan is to simply make a 5" diameter hole in the plasterboard of the ceiling and feed the pipe into the loft space, I cant think of any dangers of doing this, the roof is not felted so im asuming the hot air will work it's way out through the roof. The roof does however have some sort of strong black sheeting across the inside.

Can anyone see a problem with doing this, any potential hazards? I cant see there being a fire risk as it is just hot air but I thought I would ask people that are more in the know than I am.

Thanks for any advice.

 

[mattysupra]

most air con units send moisture through this pipe to which will lead to high moister in loft area which will cause big problems to your ceilings plus wood work and items you store in loft. Buy a 5" core drill and drill through your wall to outside (like fitting tumble dryer vent or bathroom extractor). Problem solved. You can pick up 5" drill for cheap. Brought one last week for 12 quid.

 

[Progen]

Thankyou for your suggestion Matty, but unfortunetly drilling through the wall is not an option. Which is why im struggling for a decent permanent alternative.

This is the aircon unit in question http://www.argos.co.uk/static/Product/partNumber/4140038.htm

As it has a water tank onboard, would this mean that it does not vent any water through the hot air pipe?. As such making the loft ventalition a possible alternative.

If you still think it's a bad idea to vent into loft space than I shall continue to use the window.

 

[big-all]

sheet of perspex or some wood with hole cut in to fit in window opening or part opened patio sliding double doors

or as my brother had a peice of 3by1" planed[19x69mm] draught exluder rubber around the edges
pipe at floor level and wood filling in the gap above traped in the gap and held in place by the friction on the rubber

 

[mattysupra]

i guess if it has water tank it may be o.k. How about take it into loft and then out a vent in the facer where your guttering screws to? Thats how my bathroom extractor is piped.

 

[gesseg]

Maybe put a very long hose on it?
Run the vent right to the edge of the loft. Where you should have either vents in the soffit or some other sort of air vent.

 

[JohnD]

drilling through the wall is not an option.

Why not?