Abstract: This thermostatic expansion valve (2) for heating-cooling refrigeration systems includes a body (4,8) having a transverse linear flow channel (10) therethrough. A tapered control valve element (12) divides the flow into identical inflow-outflow chambers (14,16) having equally sized inflow-outflow ports (22,24). The control valve element (12), when seated, prevents flow between the chambers (14,16), and is urged into a normally closed position by a biasing spring (26). A motor assembly (6) responsive to evaporator outlet pressure or compressor suction pressure, and temperature also controls movement of the valve element (12).

Abstract: A filter-drier unit adapted for bidirectional flow in heat pump systems. This filter-drier unit includes a shell having opposed flow ports. Spaced partitions in the shell provide a compartment therebetween, each partition separating a flow port from the compartment. An outlet check valve is connected to each partition, and a perforated tube in the compartment, extends between and interconnects the outlet check valves. A molded desiccant core in the compartment, is disposed about the tube. An inlet check valve is connected to each partition in laterally spaced relation to the outlet check valve connected to the same partition to control the flow from each flow port through an inlet check valve in one partition and into the compartment, through the core and tube thence through an outlet check valve in the other partition, and out the other flow port.

Abstract: A filter-drier unit for heat pump systems in which desiccant is located in a housing between an inlet and an outlet, a screen is provided in the housing between the inlet and desiccant for enabling a first flow from the inlet through the screen and desiccant, and a passage is provided for bypassing the desiccant and enabling a second flow from the inlet through the bypass passage, the screen collecting the desiccant upon any reverse flow for precluding migration of desiccant out of the inlet. The screen is located relative to the inlet and bypass passage so that the second flow engages and moves past the screen for washing the screen. A filter is provided in the housing between the desiccant and outlet for receiving the first flow through the desiccant and for receiving the second flow from the bypass passage prior to movement through the outlet.

Abstract: A filter-drier assembly adapted for bidirectional flow in heat pump systems. The filter-drier assembly includes a pair of bypass lines in the liquid line, each bypass line circumventing one of the expansion devices located in the liquid line. An expansion device is located ahead of the outdoor coil for use in one mode of operation and a second expansion device is located ahead of the indoor coil for use in the other mode of operation. A filter-drier unit is disposed in each bypass line, each filter-drier unit including a check valve enabling flow through the associated bypass line and filter-drier unit in one direction and precluding flow in the opposite direction. The check valve of each filter-drier unit precludes flow in the bypass line when its associated expansion device is operable in one mode of operation. The filter-drier unit includes a shell provided with an inlet and an outlet, and filtering and drying elements in the shell between the inlet and outlet.

Abstract: A filter-drier unit adapted for bidirectional flow in heat pump systems. This filter-drier unit includes an individual filter-drier in each compartment formed on opposite sides of a partition in a shell. A conduit connects the inlet of each filter-drier with the compartment other than the one in which the filter-drier is located. A check valve is connected to the outlet of each filter-drier to enable flow into the compartment in which the filter-drier is located and to preclude backflow, whereby flow into either one of the compartments through an associated shell port passes by the filter-drier in the said one compartment and through the inlet of the filter-drier in the other compartment, and thence into the said other compartment and out through its associated shell port. In one embodiment, the individual filter-driers and the fittings attaching the filter-driers to the partition are relatively laterally offset in the shell.