A system and a method are provided for returning oil in a heating, ventilation, and air conditioning system by determining when an ambient zone temperature is equal to or less than a temperature limit and reversing a direction of refrigerant flow of the HVAC system based on the length of time. In one example, a filter includes a movable pin cage that has a first pre-installation position adjacent the bottom end plate and is temporarily connected thereto by a snap connection system, and a second position adjacent the upper end plate where it performs a valve interaction function. All the blocks corresponding to a single video component within each slice can then be used as the basis for encoding the picture. The grains mixed with hulls and others are winnowed in the winnowing room so as to be sorted into two kinds: winnowed grains to be received by the winnowed conveyor, and the other including hulls to be received by a hull conveyor arranged oppositely to the winnowed grain conveyor with respect to the winnowing fan. In another aspect, the holder includes a flexible bracket and cutting blocks made of a higher durometer material than the flexible bracket.