Abstract: A monitoring device for use in monitoring the life of a filter used in the operating unit of an air conditioning system. The monitoring device has a support for use in attaching the device to the housing of the operational unit in the air conditioning system, the unit having a least one air conditioning filter holding filter material. At least one tubular arm attached to the support, each arm having an air inlet and an air outlet. The support is mounted in a manner to have a portion of the air passing through the air conditioning unit pass through the arm on the support as well. A sample filter is provided along with mounting means for removably mounting the sample filter on the arm to have air passing through the arm also pass through the sample filter. The sample filter holds the same filter material as the air conditioning filter.

Abstract: A dehumidifying system for use in a building housing a swimming pool. The system includes a refrigerant compressor, a dehumidifier coil for dehumidify ing air within the building, an air cooled condenser for reheating the air previously cooled down in the dehumidifying coil as well as for heating the swimming pool enclosure and a water cooled condensor for heating the pool water. The heat developed in the system can be used to selectively heat the dehumidified air within the building and the water in the swimming pool. The water obtained during dehumdification of the air is collected and returned to the swimming pool.

Abstract: A dehumidifying system for use in a building housing a swimming pool. The system includes a refrigerant compressor, a dehumidifier coil for dehumidifying air within the building, an air cooled condenser for reheating the air previously cooled down in the dehumidifying coil as well as for heating the swimming pool enclosure and a water cooled condenser for heating the pool water. The heat developed in the system can be used to selectively heat the dehumidified air within the building and the water in the swimming pool. The water obtained during dehumidification of the air is collected and returned to the swimming pool.

Abstract: A frost detecting device for a refrigeration unit of the type having refrigeration coils and fins. The device is adapted to be mounted on the side of the unit with frost accumulating means projecting from the unit to contact at least one fin in a manner to accumulate frost thereon at about the same rate as the fin. The device carries means for detecting a predetermined amount of frost on the accumulating means, in order to activate a defrosting cycle.