CH-18-C033 -- Development of a Method for Testing Air-Side Fouling Effects on Outdoor Heat Exchangers (RP-1705) PDF

Deposition of airside fouling on condensers degrades performance of air conditioning units. Several researchers have studied airside fouling effects on performance of heat exchangers, but much of the work focuses on evaporators. ASHRAE RP-1705, currently in progress, is intended to study condenser air-side fouling, and to characterize fouling material so that realistic fouling could be applied in laboratory measurements. Nine field-fouled split system condensing units have been collected, and fouling samples from two US locations have been collected and analyzed. A test apparatus was designed and built to study the heat transfer and air-side pressure drop through different coils before and after cleaning the condenser. A test method is proposed that will be used with this apparatus to characterize air-side fouling effects for a given heat exchanger design, independent of the condenser fan’s performance. One potential outcome of this work is that it will facilitate design of heat exchangers that are less prone or less sensitive to air-side fouling.