A primary pan assembly for use in conjunction with an air conditioning system, which includes two primary plates and a silicon rubber cover which are assembled together to form the primary pan which includes a lower cylinder to be disposed at the assembled pan during installation thereof so as to pass a pair of built drain pipes through the lower cylinder, whereby the plastic primary pan can easily be assembled with the silicone rubber plate and tightly attached to the pair of built drain pipes.

A molded plastic basepan supporting components of a room air conditioner includes a substantially rectangular bottom wall having a front edge, a back edge and left and right side edges. The bottom defines a top surface and bottom surface, and each of the edges thereof includes a structural side wall section extending upwardly therefrom in a direction substantially perpendicular to the bottom wall. A vertically extending substantially hollow structural beam is formed in the bottom wall of the basepan. The structural beam extends laterally from a location proximate the left side wall to a location proximate the right side wall. In a preferred embodiment, the bottom surface of the bottom wall is substantially planar and the structural beam is defined by a closed elongated channel extending upwardly into the basepan to define an elongated enclosed wall extending upwardly from the top surface of the bottom wall.

A condensate drain pan. The drain pan comprises a frame supporting a surface; a side outlet in the frame proximal a high point; and a bottom outlet in the surface proximal a low point. The surface is sloped so that the first side drains to the side outlet; the surface is sloped so that the second side drains to the bottom outlet; and the surface is sloped from the high point to the low point.

Using a series of identically sized, single row, single circuit refrigerant coil modules, fin/tube refrigerant coils of different nominal air conditioning tonnages are constructed by arranging different numbers of the identically sized module in accordion-pleated orientations, with each modular coil having the same depth in the direction of intended air flow across the coil. Compared to conventional "A" coils used on the indoor side of air conditioning circuits, these accordion-pleated modular coils are more compact in the air flow direction, provide more coil surface area, permit lower coil face velocities with higher fin density, and significantly reduce the overall coil manufacturing costs since only one size of coil slab needs to fabricated and inventoried to later assemble refrigerant coils of widely varying nominal air conditioning tonnages. A specially designed one piece molded condensate drain pan structure may be releasably snap-fitted onto the underside of the modular refrigerant coil, and is provided on opposite sides with support structures that are configured to slidably receive an opposed pair of interior rail members within the housing of an indoor air conditioning unit as the connected drain pan structure and modular coil are operatively inserted into the housing through an access opening therein. Accordingly, the drain pan may be secured to the modular coil, and the coil/drain pan assembly mounted within the air conditioning unit housing, without the conventional necessity of using sheet metal screws to effect these connections.

A drain spout that is easy to remove for cleaning and for accessing components behind or proximal to the drain pan. Instead of directly connecting the drain hose to the drain pan outlet spout, the drain hose connects to a drain funnel attached to or formed as a part of the shelf supporting the drain pan. The drain pan itself sits on the shelf and the outlet spout of the drain pan fits within the shelf funnel without a positive connection. The drain pan can be lifted out without disengaging the drain hose.