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Dirty Air Conditioners: Energy Implications of Coil Fouling.

DE2003805122

Publication Date	2000
Personal Author	Siegel, J.
Page Count	16
Abstract	Residential air conditioning is responsible for a substantial amount of peak electrical demand and energy consumption throughout most of the United States. Coil fouling, the deposition of indoor dusts and other particulate matter on evaporator heat exchangers, increases system pressure drop and, correspondingly, decreases system air flow and air conditioner performance. In this paper, we apply experimental and simulation results describing particle deposition on evaporator coils as well as research about indoor particle and dust concentrations to determine coil fouling rates. The results suggest that typical coils foul enough to double evaporator pressure drop in about 7.5 years, much sooner than the expected 15 - 30 year life time for an evaporator coil. The most important parameters in determining coil fouling times are the efficiency of the filter and indoor particle concentrations, although filter bypass and duct and coil design are important as well. The reduced air flows that result from coil fouling cause typical efficiency and capacity degradations of less than 5 %, however they can be much greater for marginal systems or extreme conditions. These energy issues, as well as possible indoor air quality issues resulting from fouling by biological aerosols, suggest that regular coil cleaning to ameliorate low flow and the elimination of filter bypass should be an important part of residential air conditioning commissioning and maintenance practices.
Keywords	Air conditioners Energy efficiency Residential buildings Coils Particulates Dusts Heat exchangers Energy use Air quality Air flow Energy conservation Coil fouling
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Lawrence Berkeley Lab., CA.; Department of Energy, Washington, DC.
Supplemental Notes	Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200314

Dirty Air Conditioners: Energy Implications of Coil Fouling.

Dirty Air Conditioners: Energy Implications of Coil Fouling.
DE2003805122

Publication Date	2000
Personal Author	Siegel, J.
Page Count	16
Abstract	Residential air conditioning is responsible for a substantial amount of peak electrical demand and energy consumption throughout most of the United States. Coil fouling, the deposition of indoor dusts and other particulate matter on evaporator heat exchangers, increases system pressure drop and, correspondingly, decreases system air flow and air conditioner performance. In this paper, we apply experimental and simulation results describing particle deposition on evaporator coils as well as research about indoor particle and dust concentrations to determine coil fouling rates. The results suggest that typical coils foul enough to double evaporator pressure drop in about 7.5 years, much sooner than the expected 15 - 30 year life time for an evaporator coil. The most important parameters in determining coil fouling times are the efficiency of the filter and indoor particle concentrations, although filter bypass and duct and coil design are important as well. The reduced air flows that result from coil fouling cause typical efficiency and capacity degradations of less than 5 %, however they can be much greater for marginal systems or extreme conditions. These energy issues, as well as possible indoor air quality issues resulting from fouling by biological aerosols, suggest that regular coil cleaning to ameliorate low flow and the elimination of filter bypass should be an important part of residential air conditioning commissioning and maintenance practices.
Keywords	Air conditioners Energy efficiency Residential buildings Coils Particulates Dusts Heat exchangers Energy use Air quality Air flow Energy conservation Coil fouling
Source Agency	Technical Information Center Oak Ridge Tennessee
Corporate Authors	Lawrence Berkeley Lab., CA.; Department of Energy, Washington, DC.
Supplemental Notes	Sponsored by Department of Energy, Washington, DC.
Document Type	Technical Report
NTIS Issue Number	200314