grooves 34 are not parallel to the longitudinal axis l rather the cut out portions 33 a are closer to the longitudinal axis l of the spray tube 30 than the remaining portion of the top edge 33 in a vertical direction thus water w entering the spray tube 30 will flow over the cut out portions 33 a and downward along the grooves 34 after reaching a predetermined water level within the channel body 34 the water w flowing over the cut out portions 33 a and along the grooves 34 is then directed onto the guide plates 21 and 22 positioned below the insert 32 comprises a longitudinal central rib 35 that extends coaxial to the longitudinal axis l of the channel body 31 a plurality of collars 36 extend from the longitudinal central rib 35 of the insert 32 in a direction transverse to the longitudinal axis l of the channel body 31 the collars 36 are designed to snap fit onto the channel body 31 as shown in fig6 the collars 36 have a slot 37 formed on each side so that the smooth portion s of the channel body 31 can slide therein because the water fills to the top of the channel body 31 and then flows down outside of the channel body 31 to the evaporator surface the water is prevented from traveling up slot 37 and leaking below also slot 37 allows for separation of the individual water streams via insert 32 collar 36 each collar 36 also includes a pair of spring arms 38 that clamp onto the smooth surface s of the channel body 31 when the insert is snap fit thereon the number of collars 36 is determined by the number of grooves 34 present.