To avoid the constraint of having all parts in one package, the evaporator set may be split from the condenser and the compressor going with either (see Figure 13.9).

The unit is designed as a complete system but the two parts are located separately and connected on site. On some small units, flexible refrigerant pip­ing may be provided. Larger split packages must be piped on site by normal methods, and then processed and charged as an open plant. The height of a split unit evaporator above the condenser may be limited and the supplier’s instructions should be followed. See also multi-splits, Chapter 25.

Evaporator sets, as supplied as part of a split package or for application with a condensing unit, are of three main types:

1. Air-conditioning, having the air-cooling coil with drip tray under, expansion valve, fan and motor, air filters, inlet and outlet grilles. They may also include dampers and duct connections for return and fresh air, heaters, humidifiers and various controls.


Figure 13.9 Dual circuit split system package, outdoor air-cooled condensing unit with scroll compressors matched with indoor evaporator unit, typically 50-80 kW capacity (Airedale)

2. Cold store evaporators, having the coil with drip tray under, fans, and possibly the expansion valve.

3. Cold store evaporators for use below +2°C with defrost elements.

Posted in Refrigeration and Air Conditioning