DERV (Dehumidification & Energy Recovery Ventilator):
These units represent a significant advance in ventilation technology for residential and light commercial spaces. The purpose-designed units are ideal for ventilating spaces, which are characterised by both high temperatures and high humidity levels.
DERV units take advantage of the cooling capacity of extract air to absorb heat from high-temperature ventilation air before treating this air to remove moisture in a cooling coil. This cooling coil incorporates another heat pipe to further precool the air and minimise the cooling load. Furthermore, the heat pipe reheats the overcooled air to reduce relative humidity and provide comfortable supply air ready for distribution directly to the occupied spaces.
If a supply of chilled water for the cooling coil is not available then DERVDX units, which use DX evaporator coils as the cooling coils, can be used. They are supplied with a matching condensing unit for outdoor installation.
The DERV range is available in three chilled water sizes and 4DX versions denoted by the nominal throughput of air: 150, 250, 375 and 500 (litre/second).
Energy Recovery Ventilation units (without chilled water or DX component):
ERV containing only heat recovery pipes and air moving equipment, is available as well. ERVs use the cooling potential of the extract air to provide ventilation air to space, which has been pre-cooled to an acceptable level, though without the benefit of significant dehumidification.
All DERV units are tested in line with ARI 1060 (Performance rating of air to air heat exchangers for energy recovery ventilation equipment) and ANSI/ASHRAE 84 (Method of testing air to air heat exchangers).