Substantial equipment efficiency is lost due to design and installation deficiencies, according to a new report.
According to The ACHR News, the research, undertaken by the U.S. Department of Commerce’s National Institute of Standards and Technology (NIST), presents faulty practices commonly performed by contractors and details the resultant additional energy consumption.
The recently-published report is the culmination of a three-year study that included the impact of building effects, equipment effects, and climate effects on HVAC equipment efficiency.
The study found that installation faults significantly increase annual energy consumption.
Extensive laboratory testing and computer simulations indicated that the following installation faults have the most potential to significantly degrade equipment efficiency: duct leakage, refrigerant undercharge/overcharge, low indoor airflow, and oversized equipment with undersized ductwork.
The report also shows that when two or more simultaneous faults occur, the efficiency degradations can be additive, compounding the increased energy consumption.
“This report quantifies what many industry experts already know — profound efficiency losses occur when HVAC equipment is not installed properly,” said Paul Stalknecht, ACCA president and CEO.
“This report should help consumers understand why it is important to hire a contractor who follows the QI Standard.
When consumers start asking for QI from every contractor, it will raise the performance bar in the industry, and result in significant energy savings while increasing occupant comfort.”
ACCA notes that the ANSI/ACCA 5 QI Standard, HVAC Quality Installation Specification, specifies what to measure, how to measure, and the measurement tolerances for unitary residential and commercial HVAC systems.
This reduces faults associated with design, installation, and commissioning.
Failure to meet the design and installation elements specified in the ACCA 5 QI Standard will impact equipment performance and undercut the deemed energy savings assumed by many energy efficiency programs.
A full copy of the NIST report, entitled “Sensitivity Analysis of Installation Faults on Heat Pump Performance,” can be downloaded at no charge at www.acca.org/standards/quality/.