AC System Equipment Specification, Installation And Operational Options For Improved Indoor Humidity Control

High-efficiency home designs have significantly reduced sensible cooling loads, and some building codes and IAQ standards have begun requiring continuous outdoor ventilation air. These trends have led to an increased prevalence of high indoor humidity conditions (Rudd and Henderson 2007). This paper presents a summary of low-cost or no-cost equipment selection and operation options for conventional residential air-conditioning equipment than can result in lower indoor humidity levels. These options should be evaluated and employed to the extent possible prior to considering the added first cost and operating costs of separate dehumidification equipment

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Dehumidification At Part Load

Engineers and equipment manufacturers need a better understanding of de-humidification performance at part-load conditions to evaluate the impacts of their design choices on indoor humidity levels, occupant comfort, and indoor air quality. Data from previous field test studies 1,2 show that the moisture removal capacity of a cooling coil degrades at part-load conditions - especially when the supply air fan operates continuously

Closing The Gap: Getting Full Performance From Residential Central Air Conditioners. Task 4.2-Develop New Climate-Sensitive Air Conditioner, Design, Construction, And Testing.

This study evaluated the performance of a prototype air conditioning system. The configuration of the prototype was based on detailed simulation results performed as part of this study. The results of the previously completed simulation indicated that energy-efficient, properly-ventilated homes in humid climates need equipment options or configurations that can provide a modest amount of additional dehumidification capacity while coordinating their operation with conventional cooling and ventilation systems. A prototype air conditioning system was constructed using currently available components and provides a method to independently control sensible (temperature) and latent (moisture) building loads. The prototype system was tested in both a laboratory and field setting. Laboratory tests characterized the systems performance over a wide range of operating conditions. A follow-up field test investigated the system\u27s ability to effectively control indoor temperature and relative humidity based on conventional thermostat and humidistat control.The study results indicate that this prototype air conditioner can effectively provide a comfortable indoor environment while maintaining a low first-cost and reasonable operating costs compared to other conventional equipment

Understanding The Dehumidification Performance Of Air-Conditioning Equipment At Part-Load Conditions

Air conditioner cooling coils typically provide both sensible cooling and moisture removal. Data from a limited number of field studies (Khattar et al. 1985; Henderson and Rengarajan 1996; Henderson 1998) have demonstrated that the moisture removal capacity of a cooling coil degrades at part-load conditions - especially when the supply fan operates continuously while the cooling coil cycles on and off. Degradation occurs because moisture that condenses on the coil surfaces during the cooling cycle evaporates back into air stream when the coil is off. This degradation affects the ability of cooling equipment to maintain proper indoor humidity levels and may negatively impact indoor air quality