HEALTHCARE BUILDING

AUTOMATIONGuiding 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 ISSUES1)Understand the systems

– terminal units, AHU, plant

2)Equipment over/under sizing

3)Interactions between temperature, pressure, flow and humidity control

4)Variable everything – good and bad

HEALTHCARE MONITORING AND CONTROL ISSUES

5) 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

6) 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

7) 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

8) Redundancy

Automatic backup with failures

Equipment interactions with pump failures

INSTRUMENTATION – THE STEPS

1) DDC monitoring and control

2) Validation of I/O accuracy

3) Validation of sequences of operation

4) Validation of programming – normal, off normal, failure

5) System interactions

6) Integrated system interactions

7) Tighten the belt

8) 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

MONITORINGFlows

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% RH0.004 72F at 20% RH

Economizer free cooling – cold/dry air adds humidification load

Humidifier sizing – Min or max OSA?

OR HUMIDITY VIA COOLING/CONDENSING

ORRoom

Temperature

RoomHumidity

(Maximum)

DischargeAir

Temperature

Must Be

ChilledWater

Temperature Must Be

72F 60% 57F 47F70F 60% 55F 45F68F 60% 54F 44F66F 60% 52F 42F64F 60% 49F 40F62F 60% 47F 38F

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

1) Sequencing of components that function in series

2) Hi and Lo limits

3) Occupied/Unoccupied

4) Starting is easy – when do we stop?

5) Riding it out

6) Make one change at a time.

ST. ANTHONY HOSPITAL, LAKEWOOD, CO

HEALTHCARE BUILDING

AUTOMATIONGuiding Principals,

Applications and Operation

Presented by Peter Sabeff