How long can the vent hose on a tumble dryer be?

[TEC]

Currently we have a tumble dryer which vents to the outside, however, we are soon to be moving house and want to put the tumble dryer in a location which is a bout 4m from the nearest outside wall. I don’t really want to buy a condensing dryer to replace it so I’m wondering if I can just run a 4m ventilation hose. It’ll run pretty conveniently across the top the kitchen cabinets so will not be visible, but I’m worried about the vapour coming out of the dryer condensing on the way out and ending up with water in the hose.

Anyone got any experience of this type of an arrangement?

Cheers,

TC.

 

[joned]

For what its worth my tumble dryer is in the cellar and I connected it to a redundant lined chimney exhaust (from a redundant boiler) - hard semi flexible pipe. This rises vertically at least 7 meters and the drier has been working fine for at least 4 years.
I did bend the chimney lining pipe to create a ubend at the bottom and punched a small hole in it to allow any condensate out. I probably collect less than a gallon of water from this trap every month (and the drier is on every day.
However I guess it being vertical, and hot air, adds to its efficiency over a horizontal run

 

[TEC]

Thanks joned, might put a U bend in and then the long run to the outside.

 

[markturnbull]

My dryer is also in the cellar - I had to join three hoses together and a quick measurement sees it as around 19m long

 

[cmother1]

If you can run the vent in smooth piping I would do. I'm convinced that long runs of flexible 'elephant's trunk' vent pipe cause turbulence reducing airflow and creating back-pressure. My evidence for this is my 2 bathrooms. Both have the same extractor fan, but the one connected to a flexible pipe with a couple of bends in it works crap compared to the one that goes straight through the wall via 4" soil pipe. Scientific, huh!