Session: HVAC 101 HVAC 101. Steve Sain Sain Engineering Associates, Inc. August 9, Rhode Island Convention Center Providence, Rhode Island

Session: HVAC 101 HVAC 101 Steve Sain Sain Engineering Associates, Inc. August 9, 2016 Rhode Island Convention Center Providence, Rhode Island

Why? 2

Acknowledgements 3

Disclaimer I m gonna shoot down the middle! Just not enough time for. Fans Pumps VRF VSDs Chilled Beams Control Strategies Types of Compressors Absorption Systems Evaporative Cooling ASHRAE Standards LEED Myriad of Air Distribution System Configurations Energy Conservation Measures & other.. 4

Agenda Heat & Heat Transfer Psychrometrics & Comfort Zone Vapor Compression Cycle Chillers & Chilled Water Systems Boilers & Heating Systems Air Distribution Heat Pumps & Heat Recovery HVAC Energy Efficiency 5

Do Your Best! 6

Heat & Heat Transfer The term "ton" comes from the days when cooling was done with ice. A ton of cooling capacity expresses the rate of cooling accomplished when one ton (2,000 lb.) of ice is melted in 24 hours. Since each pound of ice takes 144 Btu to melt, that's 288,000 Btu (2,000 lbs x 144 Btu/lb) per 24 hours, which is a cooling rate of 12,000 Btuh. 8

Heat & Heat Transfer Sensible Heat The heat associated with a temperature change of a substance at a constant moisture level. Latent Heat The heat associated with the phase change of a substance. Enthalpy Total heat content of a substance, including both sensible heat plus latent heat. 26

Heat & Heat Transfer How much heat is absorbed? 10

Heat & Heat Transfer Refrig Cond Press (psig) Cond Temp ( F) Evap Press (psig) Evap Temp ( F) R 134a 172 120 41 45 R 22 260 120 76 45 R 410a 418 120 130 45 Why Refrigerants? 11

Heat & Heat Transfer q Btu/hr = ṁ lb/hr x Δh Btu/lb = Btu/hr = BTUH q ṁ h T Legend Heat Flow Rate or Heat Absorption Rate Mass Flow Rate Enthalpy Temperature How can we quantify this stuff? but we (USA) work in terms of volumetric flow rates so Volumetric Flow Rate Density (ρ) Heat Capacity (c) Air CFM 0.075 lb/ft 3 0.24 Btu/lb o F Water GPM 8.34 lb/gal 1.0 Btu/lb o F 12

Heat & Heat Transfer Air: Sensible Heat Only How can we quantify this stuff? 0.075 lb 60 min 0.24 Btu q CFM T 3 ft hr lbf q CFM1.08ΔT Btu hr 13

Heat & Heat Transfer Air: Sensible + Latent Heat How can we quantify this stuff? 0.075 lb 60 min q CFM h 3 ft hr q CFM 4.5Δh Btu hr 14

Heat & Heat Transfer Water: Sensible Heat Only How can we quantify this stuff? q GPM 8.34 lb gal 60 min hr 1Btu lb F T q GPM 500 T Btu hr 15

Psychrometrics & Comfort Zone 17

Psychometerics & Comfort Zone Dry Bulb Temp Wet Bulb Temp Dew Point Temp Humidity Ratio 18

Psychrometrics & Comfort Zone 19

Psychrometrics & Comfort Zone 20

Psychrometrics & Comfort Zone 21

Psychrometrics & Comfort Zone 22

Vapor Compression Cycle 24

Vapor Compression Cycle Condenser Expansion Evaporator 25

Vapor Compression Cycle How much heat is absorbed? 26

Vapor Compression Cycle 27

Chillers & Chilled Water Systems 29

Chillers & Chilled Water Systems 30

Chillers & Chilled Water Systems 31

Vapor Compression Cycle How much heat is absorbed? 32

Boilers & Heating Systems 34

Boilers & Heating Systems 35

Boilers & Heating Systems 36

Boilers & Heating Systems Flue Gas Analysis Oxygen Trim Control

Boilers & Heating Systems Steam System 38

Boilers & Heating Systems Properties of Steam (@ 14.7 psia = 0.0 psig) Temperature (F) 350 300 250 200 150 100 50 0 1192.6 180 1150.9 Latent Heat of Vaporization 100 50 0 0 200 400 600 800 1000 1200 1400 Enthalpy (h) 39

Vapor Compression Cycle How much heat is absorbed? 40

Agenda Heat & Heat Transfer Psychometrics & Comfort Zone Vapor Compression Cycle Chillers & Chilled Water Systems Boilers & Heating Systems Air Distribution Heat Pumps & Heat Recovery HVAC Energy Efficiency 41

Air Distribution 42

Air Distribution Exhaust Air Return Air Ventilation Air Supply Air 43

Air Distribution Variable Air Volume (VAV) 44

Heat Pumps & Heat Recovery 46

Heat Pumps & Heat Recovery Air to Air Heat Pump Note: Auxiliary Heat Typically Needed at (& below) Approx 40 o F Outdoor Air Temp 47

Heat Pumps & Heat Recovery Geothermal Heat Pump Earth Typically Approx 55 o F Regardless of Season or Location 48

Heat Pumps & Heat Recovery 49

Heat Pumps & Heat Recovery Energy Recovery Ventilator 50

Heat Pumps & Heat Recovery Heat Recovery Wheel 51

HVAC Energy Efficiency Power Ton = 12,000 BTUH Watts = BTUH x 3.413 HP = 745.7 watts (or 745.7 x 3.413 = 2,545 BTUH) Efficiency EER = BTUH output / Watts input SEER = BTUH output / Watts input (avg. over ann. usage) SEER: Accounts for seasonal ambient temperature variation. Typically about 10% > EER Examples by size: Ton < 1: SEER = 30, Ton < 5: SEER = 19, Ton < 500: SEER = 15 (air cooled) 53

HVAC Energy Efficiency Efficiency COP = BTUH output / BTUH input COP = BTUH absorbed / BTUH input KW/Ton = KW input / Tons output KW/Ton = KW input / Tons absorbed Conversion? COP = EER / 3.412 Btu/Wh KW input / Tons absorbed = 12 / EER = 3.517 / COP COP typically used for chillers, influenced by air cooled or water cooled condensers Examples by condenser types: air cooled: COP = 3.8, water cooled: COP = 7.9 54

HVAC Energy Efficiency 55

Questions? 57

Session: HVAC 101 HVAC 101 Steve Sain Sain Engineering Associates, Inc. 205.979.9966 saineng.com steve.sain@saineng.com Rhode Island Convention Center Providence, Rhode Island