70 likes | 216 Views
Load Based Testing for Unitary HVAC. Ron Domitrovic Program Manager, Energy Efficiency Variable Capacity HP Subcommittee 8/28/2013. Load Based Testing of Variable Systems. Psychrometric rating testing is standard for unitary HVAC equipment 80°/67° is accepted as THE standard
E N D
Load Based Testing for Unitary HVAC Ron DomitrovicProgram Manager, Energy Efficiency Variable Capacity HP Subcommittee8/28/2013
Load Based Testing of Variable Systems • Psychrometric rating testing is standard for unitary HVAC equipment • 80°/67° is accepted as THE standard • Controlled return air conditions • Measured capacity/power/efficiency with system on. • Works well for single-speed HVAC systems
Load Based Testing of Variable Systems • Common standards: • AHRI 210/240: Systems < 65,000Btu/hr • AHRI 340/360: Systems > 65,000 Btu/hr • ANSI/AHRI 1230: VRF systems <300,000 Btu/hr
Load Based Testing of Variable Systems • Designed for fair comparison among similar systems • NOT primarily designed for energy calculation • However; generally OK with single speed systems • Difficulties with variable capacity systems THESE ARE RATING STANDARDS
Load Based Testing of Variable Systems • Why? • Current standards require fixed operation • Fixed operation may not capture actual (field) behavior • Systems can be configured for optimal operation (for rating) • May or may not match field operation • Energy use is dependant on actual operation
Load Based Testing of Variable Systems • Load Based Testing • Also called “calorimetric testing” • Load on system is held constant • No fixed control of system under test • ASHRAE TC 8.11 is exploring possibilities • Potentially more appropriate for energy calculation • More difficult—labs are not currently set up for it