joints to the outside must be made tight with high temperature resistant material (filler, putty, silicone preparation.
Gas heated tumble dryer are B22 equipment, it means they are gas equipment which depend on a aired room without any wind protection device with blower behind the burning room.
Dryer burned gas must be brought outside through a chimney.
Burn gas and humid air pipe must be the shortest possible one and it must be rising to the exhaust chimney.
In the lowest point a condenser drain must be provided, this drain derivation must observe the local rules in subject of water drain connection.
The dryer is equipped with a suction fan which produces its typical noise while working.
To reduce the noise level, a muffler can be
installed on the drain (it can be found in specialised shop).