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HEALTHCARE BUILDING AUTOMATION. Guiding Principals, Applications and Operation Presented by Peter Sabeff. SIMILAR, BUT MORE. Commercial Buildings Temperature control Building pressure control Occupied/Unoccupied control Warm up/cool down. SIMILAR, BUT MORE. Healthcare
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HEALTHCARE BUILDING AUTOMATION Guiding Principals, Applications and Operation Presented by Peter Sabeff
SIMILAR, BUT MORE Commercial Buildings • Temperature control • Building pressure control • Occupied/Unoccupied control • Warm up/cool down
SIMILAR, BUT MORE Healthcare • The above (Commercial Buildings), plus • Space & pressure relationships • Humidity control • Less influence • Warm up/cool down
HEALTHCARE CHALLENGES • Humidity Control – Humidification & Dehumidification • Air Quality • Space & Building Pressurization • Optimization – AHU and Plant Equipment
HEALTHCARE MONITORING AND CONTROL ISSUES • Understand the systems – terminal units, AHU, plant • Equipment over/under sizing • Interactions between temperature, pressure, flow and humidity control • Variable everything – good and bad
HEALTHCARE MONITORING AND CONTROL ISSUES • Unwanted gains and losses • Humidifier heat (jacketed humidifiers) • Reheat coil heat migration • Overlapping sensing and control of components in series • Fan heat • Outside air heat – roofs, hot exhaust air, condensing units • Control component failures • Lack of outside/return air mixing • Preheat coil overshoot
HEALTHCARE MONITORING AND CONTROL ISSUES • Building pressurization • Significant exhaust air – constant and variable • Many entrances/exits – high pedestrian traffic • Outside air control/conditioning issues – freezing, high humidity • Control strategies?
HEALTHCARE MONITORING AND CONTROL ISSUES • Room Control • Central cooling source - 55F +/- discharge air • Individual heating control • Thermostat location • Occupied/Unoccupied – how do we know? • Occupant thermostat manipulation • Zoning
HEALTHCARE MONITORING AND CONTROL ISSUES • Redundancy • Automatic backup with failures • Equipment interactions with pump failures
INSTRUMENTATION – THE STEPS • DDC monitoring and control • Validation of I/O accuracy • Validation of sequences of operation • Validation of programming – normal, off normal, failure • System interactions • Integrated system interactions • Tighten the belt • Repeat steps 1 through 7 until satisfied and energyuse confirms success
MONITORING Temperature and Humidity • Room temps • Terminal unit functions • AHU functions • Plant functions Pressures • AHU – internal/external • HW/CHW differential • Rooms/positive - negative • Building – positive/negative/wind
MONITORING Flows • Minimum/Maximum – OSA , Chillers, VAV • Tracking Global • Outside air temperature and humidity • Operating schedules • Building electric demand (main meter) • System electric demand (aggregate equipment)
HUMIDIFICATION Cold weather: 0.002 # moist air / # dry air (or less) 45F at 20% RH Return air: 0.006 +/- 72F at 30% RH 0.004 72F at 20% RH Economizer free cooling – cold/dry air adds humidification load Humidifier sizing – Min or max OSA?
GRAPHICS Basic • Floor plans • Terminal units • Air handling units • Heat exchangers/pumping • Chilled water • Condenser water
GRAPHICS Enhanced • AHU discharge temp, CHW valve pos, CHW S & R temps, power • System Power Consumption – pumps + fans + compressors + etc.
DATA MINING • Adds intelligence to BAS trending • 3rd party overlay • General or operator directed • Large capacity/long duration • Experience based mining / correlation of data • Must have the I/O
DATA MINING • Sequencing of components that function in series • Hi and Lo limits • Occupied/Unoccupied • Starting is easy – when do we stop? • Riding it out • Make one change at a time.
HEALTHCARE BUILDING AUTOMATION Guiding Principals, Applications and Operation Presented by Peter Sabeff