Zehnder ComfoFit Therm Insulated 90mm Dia 90 Deg Bend hood_type_downdraft 90001277 200 MM ISO 90001277 200 MM ISO PIPE 45º ELBOW x 5 up to 93% of the heat is recovered by the heat exchanger before the air is expelled into the atmosphere – at the same time air is drawn in from outside and the recovered heat is then transferred and filtered before it is distributed back into the property This rigid bend can be placed between two lengths of ComfoTube Therm 90mm to create an airtight and robust seal using the supplied O rings The insulation must be cut straight to ensure no thermal bridging once has been push fitted into the connector