Abstract: A conventional air conditioning system has a heat recovery device installed therein such that the return air from the space is passed through a heat gaining portion thereof, and the resupply air passes through a heat rejection portion thereof. Substantially 100% outside air is passed through the heat rejection portion thereof where it is cooled prior to passing through the evaporator coil and to the space to be cooled. After the return air is passed through the heat gaining portion, it is passed through the condenser coil and then discharged outside. A subcooler is preferably provided downstream of the evaporator coil, and an evaporative cooler is preferably placed upstream of the heat gaining portion of the heat recovery device to provide substantially improved cooling and dehumidification characteristics.

Abstract: In an air conditioning system designed to operate in relatively high humidity conditions, an auxiliary unit, including a complete and independent operating refrigerant circuit, is installed in air flow relationship therewith such that outdoor make-up air is caused to flow first through an auxiliary evaporator coil then through the system evaporator coil, and at least a portion of the return air is passed through an auxiliary condenser coil before being discharged outside. Energy is thereby recovered from the return air, and the make-up air is pre-conditioned to improve the dehumidifying effect of the system.

Abstract: A high latent cooling control assembly for a compression-expansion air conditioning system employs a subcooler coil disposed in the leaving air side of the indoor air evaporator coil. A liquid line branch supplies condensed liquid refrigerant from the condenser to the subcooler coil, and a flow restrictor, which can be a TXV, drops the sub-cooled liquid pressure before the refrigerant reaches the expansion device associated with the evaporator coil. A bypass line connects the condenser to the expansion device, and has a liquid line solenoid valve that is humidistat actuated. When dehumidification is called for, the solenoid is closed and refrigerant flows through the subcooler coil. When the humidistat is satisfied, the solenoid opens and the refrigerant path bypasses the subcooler coil. The high latent subcooler assembly can be field-installed or retrofitted onto an existing air conditioner.

Abstract: A fan coil condensate drain pan is made to be field adjustable to be pitched either to the fight side or to the left side when the fan coil unit is installed. This permits the drain pan to be self-draining and to be connected to a convenient field drain with a minimum of piping. The drain pan employs an elongated trough with an open upper side, and with left and right end caps. There are left and fight drain nipples that project through the respective end caps. The cabinet for the fan coil unit has left and right mounting brackets to which the left and right end caps are attached. The brackets have vertically elongated adjustment slots, and sheet metal screws or other suitable fasteners in these slots hold the end caps in place. The pitch can be selected on installation by loosening the screws on one side and lowering the end cap at that side. The drain nipple on the other side can be left open to serve as an overflow outlet.