Siphon (20; 80) comprising: - a housing with a bottom (21; 73), an upper wall (22; 75) arranged at a distance from the bottom (21; 73) and a wall (23, 24) extending between the bottom (21; 73) and upper wall (22; 75) along the periphery thereof, wherein an inflow opening is arranged in the upper wall (22; 75) and wherein the housing further comprises an outlet opening; - a siphon funnel (1; 50) comprising a tubular part (4; 51; 83), wherein one end (5; 52; 84) of the tubular part (4; 51; 83) is widened in radial direction and wherein the siphon funnel (1; 50) is arranged sealingly on the upper wall, with the widened part (4; 51; 83) in the inflow opening, and wherein the tubular part (4; 51; 83) extends toward the bottom (21; 73), - a separating wall (2; 53; 82) arranged around the tubular part (4; 51; 83) of the siphon funnel (1; 50), wherein a throughflow channel (29;) is formed between the separating wall (2; 53; 82) and the tubular part (4; 51; 83) and wherein at least one opening is provided in the separating wall (2; 53; 82) close to the widened part of the siphon funnel (1; 50) in order to provide a liquid connection between the throughflow channel (29;) and the space enclosed by the housing; and - a closing cover (3; 56) arranged in closing and removable manner on the separating wall (2; 53; 82) close to the bottom (21; 73) of the housing, wherein an opening is provided between the other end of the tubular part (4; 51; 83) and the cover (3; 56) in order to provide a liquid connection between the tubular part (4; 51; 83) and the throughflow channel (29;) characterized in that the separating wall (2; 53; 82) is arranged on the tubular part (4; 51; 83) and wherein the closing cover (3; 56) has a cover bottom and an upright wall along the peripheral edge of the cover bottom. - a housing with a bottom (21; 73), an upper wall (22; 75) arranged at a distance from the bottom (21; 73) and a wall (23, 24) extending between the bottom (21; 73) and upper wall (22; 75) along the periphery thereof, wherein an inflow opening is arranged in the upper wall (22; 75) and wherein the housing further comprises an outlet opening; - a siphon funnel (1; 50) comprising a tubular part (4; 51; 83), wherein one end (5; 52; 84) of the tubular part (4; 51; 83) is widened in radial direction and wherein the siphon funnel (1; 50) is arranged sealingly on the upper wall, with the widened part (4; 51; 83) in the inflow opening, and wherein the tubular part (4; 51; 83) extends toward the bottom (21; 73), - a separating wall (2; 53; 82) arranged around the tubular part (4; 51; 83) of the siphon funnel (1; 50), wherein a throughflow channel (29;) is formed between the separating wall (2; 53; 82) and the tubular part (4; 51; 83) and wherein at least one opening is provided in the separating wall (2; 53; 82) close to the widened part of the siphon funnel (1; 50) in order to provide a liquid connection between the throughflow channel (29;) and the space enclosed by the housing; and - a closing cover (3; 56) arranged in closing and removable manner on the separating wall (2; 53; 82) close to the bottom (21; 73) of the housing, wherein an opening is provided between the other end of the tubular part (4; 51; 83) and the cover (3; 56) in order to provide a liquid connection between the tubular part (4; 51; 83) and the throughflow channel (29;) characterized in that the separating wall (2; 53; 82) is arranged on the tubular part (4; 51; 83) and wherein the closing cover (3; 56) has a cover bottom and an upright wall along the peripheral edge of the cover bottom.