Air-conditioners condensate recovery system for buildings

Abstract

Most conventional cooling systems produce water as a byproduct, which can be recovered and put to good use. In order to product cool air from a compressed refrigerant, a set of coils allow a hot, high-pressured refrigerant to dissipate its heat and condense into a liquid. An expansion valve is then typically used to evaporate and cool the refrigerant. This cool gas then runs through a set of coils that allows it to absorb heat and cool the air, which is blown over the coils and into the inside of the building. This process cools the warm coils, so when the warm air blowing past the coils reaches its dew point the moisture in the air condenses onto the coils, producing what is essentially distilled water. This byproduct of air conditioning units is called as Condensate drain water. The quality of condensate created by Air Conditioners is typically very high, having low amounts of suspended solids, a neutral to slightly acidic pH, and low temperatures. These characteristics make the condensate adequate for several non-potable uses such as irrigation, cooling tower make-up or toilet flushing. In addition to quality water, high recovery capacity is a major benefit of these systems. Although the amount of condensate produced can vary greatly and depends on the size and operational load of the Air-conditioning system as well as the ambient temperature and humidity within a particular region. A rule of thumb created by Karen Guz (Director of the Conservation Department for the San Antonio Water System, USA) is that 0.1 to 0.3 gallons of condensate per ton of air being chilled is produced every hour that the system is operating. Seizing this opportunity by replacing or supplementing potable water with the recovered condensate can considerably reduce a building’s demand for potable water. By implementing a condensate recovery system free, clean and unused water will be replacing costly, treated, high demand potable water. Decreasing the use of potable water within buildings plays a major role in conserving municipal sources. Moreover following potential LEED credits can be achieved. Water Efficient Landscaping a. WE Credit 1.1 b. WE Credit 1.2