Nortec NHTC, NHPC User Manual

NH

TM

Series

NHTC / NHPC
ELECTRODE
STEAM HUMIDIFIER

Engineering Manual

2538144-B

PROPRIETARY NOTICE

This document and the information disclosed herein are proprietary data of WALTER MEIER LTD.
Neither this document nor the information contained herein shall be reproduced used, or disclosed to
others without the written authorization of WALTER MEIER LTD., except to the extent required for
installation or maintenance of recipient’s equipment. All re ferences to the NORTEC name should be
taken as referring to WALTER MEIER LT D.

LIABILITY NOTICE

NORTEC does not accept any liability for installations of humidity equipment installed by unqualified
personnel or the use of parts/components/equipment that are not authorized or approved by
NORTEC.

COPYRIGHT NOTICE

Copyright 2008, WALTER MEIER LTD. All rights reserved.

SPECIFICATION LABEL LOCATION

The Specification Label for your NH Series humidifier is located on the bottom of the unit. You will
find it attached to the skirt that separates the electrical and plumbing comp ar tments on the electrical
compartment side.

RECORD OF REVISIONS

For each revision, put the revised pages in your manual and disca rd the superseded pages. W rite the
revision number and revision date, date put in manual, and the incorporator’s initials in the applicable
columns on the Record of Revisions.

Revision

Number

Revision

Date

Date Put

In Manual By

Revision

Number

Revision

Date

Date Put

In Manual By

2008-10-01

TABLE OF CONTENTS

Subject Page

10-00 ELECTRODE STEAM ENGINEERING

1. INTRODUCTION WHY ELECTRODE STEAM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

A. PROPORTIONAL + INTEGRAL AUTO-ADAPTIVE CONTROL SYSTEM FOR

THE NHTC/NHPC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

B. NH CAPACITY ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

C. DRAIN CYCLE AND CYLINDER LIFE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2. PRE-INSTALLATION EQUIPMENT VERIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

A. GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

10-10 HUMIDITY, STEAM ABSORPTION AND DISTRIBUTION

1. HUMIDITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

A. ESTIMATING THE HUMIDIFICATION LOAD . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

B. LOAD CALCULATION SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

C. TEMPERATURE AND HUMIDITY REQUIRED . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

D. TEMPERATURE AND HUMIDITY AVAILABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

E. INCOMING AIR VOLUME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2. STEAM ABSORPTION AND DISTRIBUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

A. VARIABLES THAT AFFECT ABSORPTION DISTANCES. . . . . . . . . . . . . . . . . . . .28

B. CALCULATING THE DOWN STREAM HUMIDITY LEVEL . . . . . . . . . . . . . . . . . . .30

C. CONTROL OF DUCT OR PLENUM SATURATION. . . . . . . . . . . . . . . . . . . . . . . . . 31

3. STEAM RUNS AND CONDESNATE RETURNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

A. STEAM RUNS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

B. CONDENSATE RETURN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

4. STEAM DISTRIBUTORS (ASD, BSD, CSD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

A. STEAM DISTRIBUTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

B. DISTRIBUTOR CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

C. DISTRIBUTOR LOCATIONS AND MOUNTING . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

D. MULTIPLE DISTRIBUTOR APPLICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

E. LOCATION OF STEAM DISTRIBUTORS WITHIN AN AIR HANDLER . . . . . . . . . . 40

F. DISTRIBUTOR ABSORPTION DISTANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

G. TYPICAL APPLICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

H. DISTRIBUTOR DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

5. SHORT ABSORPTION MANIFOLD (SAM-e) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

A. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

B. DETERMINING THE STEAM ABSORPTION DISTANCE . . . . . . . . . . . . . . . . . . . . 43

C. STATIC AIR PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

D. CONDENSATE LOSSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

E. CORRECT CHOICE OF PRODUCT APPLICATIONS (WITHIN SAM-e) . . . . . . . . 46

F. SAM-e DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

G. SAM-e HEADER SELECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

H. SAM-e STEAM TUBE SELECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

I. SAM-e STEAM INLET CONFIGURATION SELECTION . . . . . . . . . . . . . . . . . . . . .48

J. MINI SAM-e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

6. BLOWER PACKS (BOBP, RMBP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

A. BLOWER PACKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

2008-10-01

Subject Page

7. CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

A. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

B. ON/OFF CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

C. MODULATING CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

D. OUTDOOR TEMPERATURE SETBACK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

E. TRANSDUCER SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

F. POSITIONING CONTROLS AND SENSORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

G. NORTEC ONLINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

H. NORTEC LINKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

I. TYPICAL INSTALLATION LAYOUT FOR NHTC/NHPC . . . . . . . . . . . . . . . . . . . . . 58

J. NORTEC CONTROLLER DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10-20 SPECIFICATIONS

1. HUMIDIFIERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

A. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

B. PRODUCTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

C. EXECUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

10-30 SUBMITTALS

1. SUBMITTAL DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

A. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

B. NH UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

C. DISTRIBUTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

D. SAM-e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

E. BLOWER PACK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

F. CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

WARRANTY

2008-10-01

LIST OF FIGURES

Figure Page

10-00 ELECTRODE STEAM ENGINEERING

Figure 1. NHTC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Figure 2. Optimum Boiling Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Figure 3. Conductivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Figure 4. Typical Auto-Adaptive Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 5. Capacity Setting & Cylinder Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Figure 6. Output vs Service Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Figure 7. Typical NHRS Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

10-10 HUMIDITY, STEAM ABSORPTION AND DISTRIBUTION

Figure 1. Schematic of a Typical Print Shop HVAC System . . . . . . . . . . . . . . . . . . . . . . 19

Figure 2. Psychrometric Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Figure 3. Steam Distributor Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

Figure 4. Condensate Drain Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 5. Proper Slope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Figure 6. Drain Tee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Figure 7. Steam Line Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Figure 8. Condensate Tee At Any Low Point In Steam Line . . . . . . . . . . . . . . . . . . . . . . .35

Figure 9. Trap To Prevent Steam In Condensate Line . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Figure 10. Levelling the Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Figure 11. Single Steam Distributor Installation – Minimum Clearance . . . . . . . . . . . . . . .38

Figure 12. Cutting Duct For Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39

Figure 13. Humidification Distance Nomogram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Figure 14. Best Location for Multiple Steam Distributors . . . . . . . . . . . . . . . . . . . . . . . . . .40

Figure 15. Roof Top Units 2-20 Tons – Typical Location . . . . . . . . . . . . . . . . . . . . . . . . . .41

Figure 16. Small Units On Residential Furnaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Figure 17. SAM-e Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Figure 18. Cross-Section of Distributor Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Figure 19. Absorption Distance – 3" Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Figure 20. Absorption Distance – 6" Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Figure 21. Absorption Distance – 9" Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Figure 22. Absorption Distance – 12" Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Figure 23. SAM-e Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Figure 24. SAM-e Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Figure 25. Steam Inlet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Figure 26. Typical SAM-e Installation for Atmospheric Steam Applications . . . . . . . . . . . .50

Figure 27. NH Series Humidifier With Built-On Blower Pack . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 28. NH Series Remote Mounted Blower Pack . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Figure 29. Set Point Versus Outdoor Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Figure 30. NORTEC OnLine Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Figure 31. NORTEC Online Configuration Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Figure 32. NORTEC Links Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60

2008-10-01

Figure Page

Figure 33. Humidifier Controlled by Air Proving, On/Off Duct Mounted High Limit and

Modulating Wall Mounted Space Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Figure 34. Humidifier Controlled by Air Proving, Modulating Duct Mounted High Limit

and Modulating Wall Mounted Space Controller . . . . . . . . . . . . . . . . . . . . . . . . 61

Figure 35. Humidifier Controlled by Air Proving, Modulating Duct Mounted High Limit

and Modulating Wall Mounted Return Air Sensor with Wall Mounted

Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Figure 36. Humidifier Controlled by Air Proving, Duct Mounted High Limit Sensor

and Modulating Duct Mounted Return Air Sensor with Networking Option . . . . 62

10-30 SUBMITTALS

Figure 1. Low Voltage Control Terminal Strip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Figure 2. Primary (Line) Voltage Wiring to Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

Figure 3. Physical Data - NHTC/NHPC 005-030 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Figure 4. Physical Data - NHTC/NHPC 050-100 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Figure 5. Physical Data - NHTC/NHPC 150-200 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Figure 6. Distributor Dimensions (3 Sheets) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Figure 7. SAM-e General Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Figure 8. General Mini SAM-e Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Figure 9. In-Duct/AHU Installation Without Mounting Frame Installation . . . . . . . . . . . . . 87

Figure 10. In-Duct/AHU Installation With Mounting Frame Installation . . . . . . . . . . . . . . . . 88

Figure 11. Outside Duct Installation Without Mounting Frame Installation . . . . . . . . . . . . . 89

Figure 12. Outside Duct Installation With Mounting Frame Installation . . . . . . . . . . . . . . . . 90

Figure 13. Vertical Duct Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Figure 14. Outside Duct Mounting Cover Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Figure 15. Atmospheric SAM-e Adapter Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Figure 16. Atmospheric Steam Header and Adapter Configuration . . . . . . . . . . . . . . . . . . 93

Figure 17. Physical Data for Remote Mounted Blower Pack . . . . . . . . . . . . . . . . . . . . . . . 94

Figure 18. Physical Data Units With Optional Built-On Blower Packs . . . . . . . . . . . . . . . . . 95

Figure 19. Wall Digital Humidistat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Figure 20. Duct Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

2008-10-01

LIST OF TABLES

Table Page

10-00 ELECTRODE STEAM ENGINEERING

Table 1. Features Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Table 2. NHTC/NHPC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

10-10 HUMIDITY, STEAM ABSORPTION AND DISTRIBUTION

Table 1. Outdoor/Indoor Relative Humidity Conversion Chart . . . . . . . . . . . . . . . . . . . . 14

Table 2. Load Calculation Summary Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

Table 3. Grains of Water Per Cubic Foot – Saturated Air (100% rh) . . . . . . . . . . . . . . . 15

Table 4. Design Outdoor Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Table 5. Inside Relative Humidities At Which Moisture Will Condense On Windows . . 21

Table 6. Regain of Hygroscopic Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Table 7. Design Indoor Conditions For Various Places, Products and Processes . . . . . . 23

Table 8. Variables That Affect Absorption Distances . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 9. Typical Absorption Distances, Single Distributor, 100 lbs/hr Humidifier . . . . . . .29

Table 10. Water (lbs/hr) Contained in 1000 CFM of Air . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Table 11. Steam Line Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Table 12. Recommended Material and Size for Steam Run . . . . . . . . . . . . . . . . . . . . . . .33

Table 13. Recommended Condensate Line at Distributor(s) . . . . . . . . . . . . . . . . . . . . . . . 33

Table 14. Maximum Recommended Length of Steam Runs . . . . . . . . . . . . . . . . . . . . . . . 34

Table 15. Air Pressure Loss in AHU/Duct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Table 16. Condensate Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46

Table 17. SAM-e Tube Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Table 18. Mini SAM-e Headers – 3" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Table 19. Mini SAM-e Headers – 6" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Table 20. Mini SAM-e Tubes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Table 21. Mini Inlet Configurations – For Atmospheric Steam Unit . . . . . . . . . . . . . . . . . . 49

Table 22. Ceiling and Frontal Clearances for Blower Packs . . . . . . . . . . . . . . . . . . . . . . .52

10-30 SUBMITTALS

Table 1. NH Series Unit Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .99

Table 2. Common Accessories Universal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Table 3. Steam Distributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100

Table 4. Steam Distributor Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101

Table 5. SAM-e Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

Table 6. Adjustable Mounting Frame for SAM-e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Table 7. SAM-e Tube Matrix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Table 8. SAM-e Inlet and Adapter Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110

Table 9. Remote Blower Pack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111

Table 10. Built-On Blower Pack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Table 11. Controls – ON/OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112

Table 12. Modulating Control By NORTEC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .112

2008-10-01

Table Page

Table 13. Modulating Demand Signal By Others Single Channel. . . . . . . . . . . . . . . . . . . 113

Table 14. Modulating Demand Signal By Others Dual Channel. . . . . . . . . . . . . . . . . . . . 113

Table 15. Modulating By Other Transducer Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

Table 16. NORTEC OnLine Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Table 17. NORTEC Links Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Table 18. NH Series Fusing Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

2008-10-01

10-00

INTRODUCTION

10-00

Page 1
2008-10-01

Figure 1. NHTC

10-00

Page 2

2008-10-01

1. INTRODUCTION

The NHTC humidifier is controlled by Nortec’s Patented Auto adaptive Water Management
Control System. This system allows the humidifiers to adapt to basically any potable
incoming water and changes that occur to the water supply. This eliminates the need to
readjust drain timers, changes complete cylinders or time consuming adjustment of
electrode spacing’s. The system also adjusts the drain rate of the humidifier to reduce the
amount of drain water exiting the humidifier as water conditions change. This reduces
energy loss due to excessive draining of hot water and extends cylinder life since less water
and minerals enter the humidifier.

The following is a brief description of how the Auto-Adaptive water Management System
works.

The electrode steam system produces pure uncontaminated steam with variable output
through electronic power control of the electrodes. Water borne minerals remain in the
cylinder and are periodically flushed out through the automatic cylinder drain. On NHTC and
NHPC models the drain automatically empties the steam cylinder if it is not operated for
three days. Solid mineral scale sinks to the bottom of the cylinder which, when filled with
residue, is easily removed and replaced.

A. PROPORTIONAL + INTEGRAL AUTO-ADAPTIVE CONTROL SYSTEM FOR THE

NHTC/ NHPC

(1) NORTEC’s patented P+I Auto-Adaptive control system allows the unit to operate at

an optimal low water level using the same fixed electrode spacing regardless of the
incoming water conditions. Boiling of the water allows the minerals in the water to
remain behind in the cylinder. This raises the contained water conductivity to a
value higher than the incoming water. The P+I Auto-Adaptive control system
monitors and adjusts the contained water conductivity as these changes occur.

(2) The humidifiers are designed to produce full steam output at the lowest possible

electrode coverage to obtain maximum cylinder life.

(3) The units operate between A and D of the main steam output demand.

Accordingly, the current flow between the electrodes in the cylinder is maintained
between these pre-established limits programmed into the P+I Auto-Adaptive
control system.

(4) As the water boils away and the electrode coverage is reduced, the steam output is

also reduced slightly. A pre-determined design parameter of every NORTEC
cylinder is the known time (To) (time optimum) that it takes to boil down from A to
D of output (also referenced to as amp trigger points) at a pre-designed contained
water conductivity. (See Figure 2.)

(5) Whenever the conductivity in the cylinder water is lower than the designed

conductivity, the (Ta) (time actual) to boil down from A to D will be longer than the
To. (See Figure 3.)

10-00

Page 3
2008-10-01

(6) As the water is boiled away, the minerals left behind increase the conductivity of

the water in the cylinder. As soon as the conductivity is greater than design, the Ta
to boil from A to D will be shorter than To and a drain cycle is initiated.

(7) The fill valve always opens during timer drains, adding cold water to mix with the

hot water from the cylinder during automatic drain cycles. This tempering process
is required to meet plumbing codes.

(8) As can be seen from a typical sequence depicted in Figure 4, the P+I Auto-

Adaptive system allows the unit to be self-regulating. It drains only when necessary
and only the amount of water to maintain optimum operating conditions.

(9) Relying on the proportional (P) feedback only to decide how much to drain is like

guessing what is happening based on a ‘snapshot’ only. By taking into
consideration a series of “snapshots”: (one from each of the past ten cycles for
example), the control system has more data on which to base its decision to drain.
The integral (I) part of the P+I Auto-Adaptive system provides this added feedback.

(10) The proportional (P) and integral (I) factors have been weighted as to the relative

influence each will have when the NHTC/NHPC calculates a drain. The
preprogrammed weighing was derived through extensive field and laboratory tests.
When supply water conductivity is extremely high (requiring substantially more
drains), the NHTC/NHPC will see the pattern developing in cycles stored in
memory. It will then initiate additional drains to adjust the contained water
conductivity.

(11) If low conductive water conditions occur, the P+I control will reduce the drains

necessary to maintain optimum operating conditions within the cylinder. If extreme
water conditions are encountered, the NHTC/NHPC can be reprogrammed with
factory instructions to compensate.

(12) NORTEC’s P+I Auto-Adaptive control system has been designed to benefit users

who demand very tight control of the relative humidity. It maintains steam output
above the B level, even during auto drains. (See Figure 4.)

(13) The P+I Auto-Adaptive control system allows the humidifier to maintain tighter

humidity control without the problem of rh depression during drain cycles that occur
with other humidifiers. This results in more consistent space rh levels, even with a
simple on/off control system.

10-00

Page 4

2008-10-01

Figure 2. Optimum Boiling Time

Figure 3. Conductivity

10-00

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2008-10-01

B. NH CAPACITY ADJUSTMENT

(1) Each NORTEC NH Series humidifier is rated at its maximum output capacity. By

means of the alphanumeric display and keypad on the NHTC/NHPC, the
humidifiers can be adjusted to obtain an output between 20% and 100% of its rated
capacity.

C. DRAIN CYCL E AND CYLINDER LIFE

(1) Water Type Used (Potable or Softened)

(a) The electrode steam product line is one of the most efficient humidifier

systems since it uses the minerals in the water to conduct electricity. If no
minerals are present no current can pass from one electrode to another, thus
no steam production can occur.

(b) Although the electrode steam humidifier is ideal for potable water, it should

not be used with pure reverse osmosis or deionized water since the
conductivity is too low.

(2) Water Conditions vs Cylinder Life

(a) The NH Series is designed to adapt to most potable or softened water

supplies. Since the output of all NH Series humidifiers is pure, clean steam,
minerals originally in the incoming water are left behind in the steam cylinder.
Many of these minerals will be removed during short flush cycles within the
cylinder. Therefore, the water chemistry, the unit running time, and output
capacity setting ultimately determines the cylinder life. (See Figure .)

(3) Output vs Cylinder Life

(a) As minerals build-up on the electrodes in the cylinder of the NORTEC NH

Series humidifier, the patented P+I Auto-Adaptive control system
automatically raises the water level slightly in the cylinder. This exposes fresh
electrode surface to the water and maintains peak output and efficiency from
the humidifier. Once the

(b) electrode surface is completely encrusted by the minerals, the user is alerted

to change the cylinder. Other humidifiers’ performance degrades gradually as
the minerals build-up. The NH Series maintains maximum efficiency then the
cylinder is replaced. (See Figure .)

(4) Water Conditions vs Drain Rate

(a) The P+I Auto-Adaptive control system automatically adjusts the drain rate to

maintain the design water conductivity required for proper operation. This
ensures regular flushing of minerals which become concentrated in the water,
and minimizing wastage of hot water. The humidifier automatically adjusts it’s
drain rate with changes in incoming water conductivity through the Auto­adaptive water management system.

10-00

Page 6

2008-10-01

0. Store previous cycle’s drain decision in integral (l) memory.

1. Fill to A trigger (use all places below 1-10).

2. Boil to C trigger without timing to allow previous fill water to mix thoroughly during boiling.

3. Boil from C to D while monitoring time (T actual).

4. Decide how long (how much) to drain, then fill to B.

5. Drain according to the P+I calculated drain time, fill on to control outlet temperature.

6. At D, stop draining and postpone remaining drain, fill to B.

7. Continue remaining drain.

8. With drain finished, fill to A.

9. Boil to D, timing from C to D.

10. Decide how long to drain (in this case zero) based on present and past cycles.

Figure 4. Typical Auto-Adaptive Operation

10-00

Page 7
2008-10-01

It is important to note that the drain rate shown includes the make-up water,
mixed with the drain water, which tempers the drain water to 140°F (60°C) or
less.

NOTE

The electrode steam process provides optimum efficiency because all resistance to
current passage is converted to usable energy. Unlike cal-rod or infrared humidifiers
which convert some of their capacities into unusable heat.

Figure 5. Capacity Setting & Cylinder Life

Figure 6. Output vs Service Life

10-00

Page 8

2008-10-01

3. PRE-INSTALLATION EQUIPMENT VERIFICATION

A. GENERAL

(1) Ensure the available voltage and phase correspond with humidifier voltage and

phase as indicated on the humidifier’s specification label.

(2) Ensure that the external fuse disconnect is sufficient size to handle the rated

amperage as indicated on the humidifier’s specifications label. Refer to local building

codes.
(3) Report any discrepancy immediately to the site engineer.
(4) Location and mounting is described in Chapter 10-10.
(5) For typical installation see Figures 6 & 7.

10-00

Page 9
2008-10-01

Figure 6. Typical NHRS Installation (Sheet 1 of 2)

10-00

Page 10

2008-10-01

10-00

Page 11
2008-10-01

Figure 7. Typical NHRS Installation (Sheet 2 of 2)

10-10

HUMIDITY,

STEAM ABSORPTION

AND

DISTRIBUTION

10-10

Page 12

2008-10-01

HUMIDITY, STEAM ABSORPTION AND DISTRIBUTION

1. HUMIDITY

A. ESTIMATING THE HUMIDIFICATION LOAD

Note: The humidification load can easily be calculated by using Nortec’s Humidification Engineering
and Load-sizing Program (HELP). The softward can be downloaded at www.humidity.com

(1) Relative humidity is the percentage of moisture in the volume of air at a given

temperature, compared to the maximum amount of moisture that the volume of air can
hold at the same temperature and atmospheric pressure. As air becomes warmer, it
can absorb more moisture per unit volume. Therefore a quantity of air containing a
specific amount of moisture will have different values of relative humidity as the
temperature changes.

(2) It is this process that causes dry air in building. As cold incoming air is heated, its

relative humidity value drops. Therefore moisture must be added to attain an
acceptable level of humidity within the building. Determining how much moisture must
be added is the object of this brochure. Table 2 simplifies the calculations which are
described here in detail.

B. LOAD CALCULATION SUMMARY

(1) In order to determine the humidification load three basic values need to be known:

(a) The design conditions of the humidified space, i.e., the temperature and humidity

required.
(b) The conditions of the incoming air, i.e., the temperature and humidity available.
(c) Incoming air volume and secondary conditions that can affect the humidification

load.

(2) Data and calculations required to estimate humidification load are described in

Tables 1, 2 and 3.

C. TEMPERATURE AND HUMIDITY REQUIRED

(1) The design temperature and humidity of a space depends mostly upon the job being

performed. Once the design temperature and humidity have been established, the
required moisture can be found in gr/ft
worst case (highest temperature, highest humidity).

(2) Formula 1

For example:

The press room of a printing plant should be kept at 76 - 80

Therefore, the worst case is 80

From Table 3 the required moisture is 11.04 gr/ft

D. TEMPERATURE AND HUMIDITY AVAILABLE

(1) The outdoor conditions tell us the moisture available in the incoming air. Approximate

values can be obtained from Table 4 and combined with Table 3 to find moisture
available. Once again we must take the worst case (here, it is lowest temperature,
lowest humidity). As can be seen, the contribution of moisture from the outside air is
almost zero.

3

from Table 3. Remember always to take the

°F with 43% - 47% rh

°F, 47% rh.

3

x 47% = 5.19 gr/ft

3

10-10

Page 13

2008-10-01

Table 1. Outdoor/Indoor Relative Humidity Conversion Chart

100%2456791217192329364352

95%2346791216172228344150
90%2345681115162126313948
85%2345681114152024293745
80%2345671013151923273542
75%2344571012141822263339
70%123456911131720243136
65%123445810121519232934
60%12334579111417212631
55%11334478101316192429
50%1123346891214182226
45%1123346781113162024
40%1122345771012141821
35%112224566910121518

Outdoor relative humidity

30%01222345679111315
25%0111233455791113
20%011122334557910
15%00111123344568
10%00011122233346

5%00000011122233
0%00000000000000

-20° -10° -5° 0° +5° +10° +15° +20° +25° +30° +35° +40° +45° +50°

Chart shows what the residual indoor RH would be at 70°F under varying outdoor conditions if a proper humidification
system were not installed in the building. Studies indicate that the recommended RH should be between 40% and 60%
for optimum benefits to the occupants.

Outdoor temperature

Table 2. Load Calculation Summary Sheet

Determine the moisture required in the space (Table 3)

Grains from Table 3 at space temp. ______ x Indoor RH

Determine the moisture level of incoming air (Table 4)

Grains from Table 4 at space temp. ______ x Outdoor RH

Therefore: moisture to be added: (moisture) M - A - B ______ gr/ft3 →M ______ gr/ft
Determine the volume of air to be humidified. Choose the largest

value.

1. Natural ventilation: Volume x number of air changes.

2. Exhaust air: CFM x 60 min/hr

3. Make-up air: CFM x 60 min/hr
Therefore: Gross humidification load = L (load) = MxC = ______ lbs/hr →L ______ lbs/hr

7,000

NOTES: 1. 7,000 grains = 1 pound

2. If HVAC system uses economizer cycle, check load using formula 6.

= A ______ gr/ft

= B ______ gr/ft

______ ft
______ ft
______ ft

3

3

3

/hr

3

/hr

3

/hr →C ______ ft3/hr

10-10

Page 14
2008-10-01

3

Table 3. Grains of Water Per Cubic Foot – Saturated Air (100% rh)

°C °F Grains °C °F Grains °C °F Grains °C °F Grains °C °F Grains °C °F Grains

-23 -10 .29 4 40 2.86 58 5.41 76 9.75 35 95 17.28 1 14 29.34

-5 .35 41 2.97 59 5.60 77 10.06 96 17.80 115 30.13

-18 0 .48 42 3.08 16 60 5.80 78 10.40 97 18.31 49 120 34.38
8 .61 43 3.20 61 6.00 79 10.80 98 18.85 125 39.13

-12 10 .78 44 3.32 62 6.20 27 80 11.04 99 19.39 54 130 44.41

-9 15 .99 7 45 3.44 63 6.41 81 11.40 38 100 19.95 135 50.30

-7 20 1.24 46 3.56 64 6.62 82 11.75 101 20.52 60 140 56.81

-4 25 1.56 47 3.69 18 65 6.85 83 12.11 102 21.11 145 64.04

-1 30 1.95 48 3.83 66 7.07 84 12.49 103 21.71 66 150 72.00
31 2.04 49 3.97 67 7.31 29 85 12.87 104 22.32 155 80.77
32 2.13 10 50 4.11 68 7.57 86 13.27 41 105 22.95 71 160 90.43
33 2.21 51 4.26 69 7.80 87 13.67 106 23.60 165 101.00
34 2.29 52 4.41 21 70 8.10 88 14.08 107 24.26 77 170 112.60

2 35 2.38 53 4.56 71 8.32 89 14.51 108 24.93 175 125.40

36 2.47 54 4.72 72 8.59 32 90 14.94 109 25.62 82 180 139.20
37 2.56 13 55 4.89 73 8.87 91 15.39 43 110 26.34 185 154.30
38 2.66 56 5.06 74 9.15 92 15.84 111 27.07 88 190 170.70
39 2.76 57 5.23 24 75 9.45 93 16.31 112 27.81 195 188.60

94 16.79 113 28.57

(2) Formula 2

Assume our printing plant is located in Denver, Colorado. From Table 4, the worst
case is -10

From Table 3:

0.29 gr/ft

°F with 37% rh

3

x 37% rh - 0.11 gr/ft

3

Combining this result with that of Moisture Required (A) we see that we will need

5.19 - 0.11 = 5.08 grains of moisture for every cubic foot of outside air brought in.

E. INCOMING AIR VOLUME

(1) The following outlines the steps necessary to determine the amount of outside air being

brought into the humidified space and the corresponding amount of moisture required.
There are three basic means by which outside air is introduced into the humidified
space. These are:

(a) Through natural ventilation, for example, opening and closing doors and windows,

and by infiltration through cracks and openings in the building construction.

(b) Through mechanical ventilation, for example, the introduction of make-up air, or

the exhausting of stale air by the building HVAC system.

(c) Through the economizer section of the HVAC system - if this feature is included in

the system.

(2) For maximum accuracy, all three should be estimated and the largest chosen.

10-10

Page 15

2008-10-01

Table 4. Design Outdoor Conditions

JANUARY

Relative Humidity

(% RH)

State City °C

Alabama Birmingham

Arizona Flagstaff

Arkansas Little R o ck -15 5 80 67 68 95 85 55 59 35
California Eureka

Colorado Denver

Connecticut New Haven -18 0 75 65 69 95 77 64 74 35
Delaware Wilmington -18 0 77 62 70 95 80 52 69 35
District of

Columbia
Florida Jacksonville

Georgia Atlanta

Idaho Boise

Illinois Cairo

Indiana Fort Wayne

Iowa Davenport

Kansas Dodge City

Kentucky Louisville -18 0 78 68 69 95 77 52 57 35
Louisiana New Orleans

Maine Portland -21 -58165749078587632
Maryland Baltimore -18 07268569571526535

Massachusetts Boston -18 0 72 59 67 92 72 55 70 33
Michigan Detroit

Minnesota Duluth

Mississippi Vicksburg -12 10 82 65 67 95 87 61 70 35

Missouri
Montana Billings

Nebraska North Platte

Nevada Reno -21 -58267549572252035
New HampshireConcord -26-157860699080496932

Mobile

Phoenix
Yuma

Fresno
Los Angeles
Sacramento
San Diego
San Francisco

Grand Junction
Pueblo

Washington -18 0 73 56 64 95 78 52 64 35

Miami

Augusta
Savannah

Lewiston

Chicago
Peoria

Indianapolis
Terre Haute

Sioux City

Topeka

Shreveport

Grand Rapids

Minneapolis

Kansas City
St. Louis

Butte

Omaha

Dry

Bulb

-12

-12

-23

-4

-1

-1

-4
2

-1
2
2

-23

-26

-29

-4
2

-12

-12

-7

-23

-20

-18

-23

-23

-23

-23

-18

-26

-29

-23

-23

-7

-7

-23

-23

-32

-29

-23

-18

-32

-29

-29

-23

°F

10
10

-10
25
30

30
25
35
30
35
35

-10

-15

-20

25
35

10
10
20

-10

-10

-10

-10

-10

-15

-20

-10

-10

20
20

-10

-10

-25

-20

-10

-25

-20

-20

-10

7:30
A.M.

-5
0

0

0

81

83
75
56

87
93
63
90
76
84

54
77
67

89
87

80
84
83

82
79

81
81
83

84
83
82

78
78

78

85
83

82
85

78
82

78
77

67
76

80
82

1:30
P.M.

--

--

61

58
47
37

80
46
82
58
68

37
64
44

56
59

64
59
58

75
73

69
70
72

75
72
70

67
57

64

67
67

71
78

74
72

64
65

73
70

62
68

7:30
P.M.

--

--

--

Dry

Bulb

°F

66

39
27

77
66
51
70
60
70

41
64
48

75
75

69
69
72

74
71

75
77

81
78
76

72
61

6795100

73
6695100

77
80

74
75

6668100

60
71

66
73

95

--

95

--

90
105
110

90
105

90
100

85

85

95

95

95

95

91

95

98

95

95

95

--

98

95

96

95

95

95

--

95

95

95

95

93

95

95

90

95

85

95

7:30
A.M.

JULY

Relative Humidity

(% RH)

84
90

77
53
51

92
61
85
76
86
92

55
48
73

85
83

83
83
85

54
64

83
78
81

84
84
77

86
77

85

84
86

74
76

87
82

76
73

65
82

84
80

1:30

P.M.

--

56
64

36
31
31

36
50
46
68
75

27
27
34

57
64

57
55
61

34
37

57
51
53

53
54
50

55
45

54

64
56

50
51

61
54

48
50

40
36

50
51

7:30
P.M.

--

--

68
78

23
23

80
20
54
28
65
78

30
22
35

76
76

68
69
80

23
25

55
58

58
60
56

54
52

54

72
62

56
54

66
54

47
55

33
33

46
51

°C

35
35

--

32
41
44

32
41
32
38
29
29

35
35
35

35
33

35
37
35

35
35

--

37
35
35

35
35
35

--

35
35

35
38

35
38

35
35

33
35

38
35

32
35

29
35

10-10

Page 16
2008-10-01

Table 4. Design Outdoor Conditions (cont)

JANUARY

Relative Humidity

(% RH)

74
65
68

71
78
66
79

69
69

74
79
76
75

78
78

65
68
63

76
65

76
67

69
73

52
75
62
39
73
59

74
78

70
74

73
73

Dry

Bulb

--

°F

95
95
95

93
93
95
95

93
95

95
95
95
95

90
90

95
95
95
95

95
95

95
95

95
95

100

95
100
100

95
100

85

95

95

95

95

95

87

86

84

91

96

87

94

85

73

80

80

7:30
A.M.

State City °C

New Jersey Atlantic City

Newark

Trenton
New Mexico Albuquerque -18 0 68 51 46 95 59 33 28 35
New York Albany

Buffalo

New York

Rochester
North Carolina Asheville

Raleigh
North Dakota Bismarck -34 -30 77 71 75 95 85 52 49 35
Ohio Cincinnati

Cleveland

Columbus

Toledo
Oklahoma Oklahoma City -18 0 79 62 65 101 80 49 51 38
Oregon Baker

Portland
Pennsylvania Harrisburg

Philadelphia

Pittsburgh

Scranton
Rhode Island Providence -18 0 73 60 67 93 79 57 73 34
South Carolina Charleston

Columbia
South Dakota Huron

Rapid City
Tennessee Knoxville

Memphis
Texas Amarillo

Corpus Christi

Dallas

El Paso

Houston

San Antonio
Utah Salt Lake City -23 -10 80 71 72 95 56 27 23 35
Vermont Burlington -23 -10 81 69 78 90 76 54 67 32
Virginia Richmond -9 15 84 60 68 95 81 57 72 35
Washington Seattle

Walla Walla
West Virginia Charleston

Parkersburg
Wisconsin Green Bay

Milwaukee
Wyoming Cheyenne -26 -15 59 48 55 95 73 36 40 35

Province City

Alberta Calgary

Edmonton

Grande Prairie

Lethbridge

Medicine Hat
British Columbia Estevan Point

Fort Nelson

Penticton

Prince George

Prince Rupert

Vancouver

Dry

Bulb

-15

-18

-18

-23

-21

-18

-21

-18

-12

-18

-18

-23

-23

-21
12

-18

-18

-18

-21

-9

-12

-29

-29

-18

-18

-23

-7

-12

-12

-7

-7

-9

-21

-18

-23

-26

-26

-34

-34

-42

-36

-34

-8

-40

-18

-38

-12

-9

°F

-10

10

-10

-10

10

15
10

-20

-20

-10
20
10
10
20
20

15

-10

-15

-15

-29

-29

-43

-32

-30
17

-40

-37
11
15

7:30

A.M.

5
0
0

-5
0

-5
0

0
0

-5

0
0
0

-5

0
0

-5
0

0

79
72
73

75
79
72
81

82
82

82
81
83
79

83
87

72
74
77
80

87
81

79
71

83
82

71
88
81
63
85
82

86
80

79
82

75
76

1:30
P.M.

71
75
80
66
73

84
79
81
82
87
87

68
79
62

63
72
61
73

59
57

70
72
71
72

81
82

49
65
67
67

55
57

72
69

65
67

51
66
62
45
66
60

80
74

64
66

68
70

7:30
P.M.

JULY

Relative Humidity

(% RH)

81
75
77

79
78
75
80

88
86

84
79
78
76

69
86

78
78
80
77

88
83

86
71

83
85

77
93
79
60
90
88

86
50

88
80

85
81

1:30
P.M.

34
42
38
30
31

32
32
44
53
54
41

72
51
55

52
53
58
50

56
55

52
52
52
52

68
63

51
52
52
50

64
56

52
42

55
55

43
58
50
37
58
49

63
33

53
52

58
58

7:30
P.M.

82
65
68

64
63
68
60

73
72

60
58
60
59

36
48

62
64
63

82
68

49
40

66
59

42
68
47
30
66
45

47
22

67
65

64
64

°C

35
35
35

34
34
35
35

34
35

35
35
35
35

32
32

35
35
35
35

--

35
35

35
35

35
35

38
35
38
38
35
38

29
35

35
35

35
35

31
30
29
33
36

31
34
29
23
27
27

10-10

Page 17

2008-10-01

Table 4. Design Outdoor Conditions (cont)

JANUARY

Relative Humidity

(% RH)

Province City °C

Manitoba Brandon

Churchill
The Pas
Winnipeg

New Brunswick Campbellton

Fredericton
Moncton
Saint John

Newfoundland Corner Brook

Gander
Goose Bay
St. John’s

N.W.T. Frobisher

Resolute
Yellowknife

Nova Scotia Halifax

Sydney
Yarmouth

Ontario Thunder Bay

Hamilton
Kaspuskasing
Kingston
Kitchener
London
North Bay
Ottawa
Peterborough
Sioux Lookout
Sudbury
Timmins
Toronto
Windsor

Sault St. Marie
P.E.I. Charlottetown -21 -6 86 84 57 29
Quebec Knob Lake

Mont Joli

Montreal

Port Harrison

Quebec City

Sept-Iles

Sherbrooke

Trois Rivieres
Saskatchewan Prince Albert

Regina

Saskatoon

Swift Current
Yukon Territory Dawson

Whitehorse

Dry

Bulb

-34

-40

-37

-34

-28

-27

-24

-24

-23

-21

-32

-17

-43

-45

-45

-18

-17

-15

-33

-18

-34

-24

-19

-18

-29

-27

-25

-36

-29

-36

-19

-16

-29

-40

-24

-27

-39

-28

-33

-28

-28

-41

-37

-37

-34

-49

-43

°F

-29

-40

-35

-29

-18

-16

-12

-12

-10

-26

-45

-49

-49

-27

-30

-11

-20

-17

-13

-33

-20

-33

-20

-40

-11

-16

-39

-19

-27

-18

-18

-41

-34

-34

-29

-56

-45

7:30
A.M.

-5
1

0
1
5

0

-3
0

-3

-3

1:30
P.M.

73
76
77
78

77
72
82
82

84
76
85

77
71
82

83
84
83

80
75
79

84
80
77

77
78
81
79
82

79
75

76
81

77
81
76
79

76
80

7:30
P.M.

Dry

Bulb

°F

90
79
85
90

87
89
88
81

84
85
86
79

63
54
78

83
84
76

86
91
87
85
88
90
87
90
90
65
89
90
90
92
88

55
62
88

86
80
87
88

88
92
90
93

57
78

7:30
A.M.

JULY

Relative Humidity

(% RH)

1:30

P.M.

50
57
54
50

54
47
52
62

47
45
42
60

67
81
50

50
56
70

52
52
52
69
58
53
46
50
53
69
44
45
56
51
48

70
71
58

60
47
58
58

60
40

7:30
P.M.

°C

32
26
29
32

31
32
31
27

29
29
30
26

17
12
26

28
29
24

30
33
31
29
31
32
31
32
32
18
32
32
32
31
29

13
17
31

30
27
31
31

31
33
32
34

14
26

10-10

Page 18
2008-10-01

(3) Using the natural ventilation method requires knowing the volume of the humidified

space and the type of construction. A tightly constructed building will have a least one
air change per hour. A loosely constructed building will have at least one and one half
changes per hour, and this same building with a large a amount of incoming or exiting
traffic will have at least two air changes per hour.

(a) Formula 3

Assume our print shop has a floor area of 100'
large amount of traffic. This requires

100' x 100' x 20' x 2 = 400,000 ft
Using our example, the moisture required is
400,000 x 5.08

_______________

7000 grains/lb

(4) Using make-up air:

(a) Formula 4

Assume our print shop has a 15,000 CFM HVAC system and uses 10%
make-up air during winter. The amount of outside make-up air entering the
HVAC system will, therefore, be 10% of 15,000 CFM = 1,500 CFM. The
moisture required will be

1,500 x 5.08 x 60 min/hr

_________________________

7,000 grains/lb

(Refer to Figure 1.)

= 290 lbs/hr

= 65 lbs/hr

3

x 100' with a 20' ceiling with a

/hr.

Figure 1. Schematic of a Typical Print Shop HVAC System

10-10

Page 19

2008-10-01

(5) Using an exhaust air fan:

(a) Formula 5

Assume the print shop has a 1,000 CFM fan to exhaust a drying room. The
moisture required to humidify the drying room only is

1,000 x 5.08 x 60 min/hr

_________________________

7,000 grains/lb

= 44 lbs/hr

(Refer to Figure 1.)

(6) Using an economizer cycle:

(a) Care should be taken in sizing humidification load when an economizer cycle is

incorporated into a building HVAC system. The purpose of an economizer cycle is
to provide building cooling using outside air, rather then the building refrigeration
system when outside air conditions permit.

(b) The economizer cycle senses and compares outdoor air temperature and return

air temperature during the cooling season.

(c) W hen the HVAC system calls for cooling and the outdoor air temperature is low

enough – typically 55°F or lower – the outside air and exhaust air dampers are
positioned to provide the required supply air temperature to maintain cooling, and
the recirculated air damper is positioned to maintain the required supply air
volume. When the outdoor air temperature is higher than the supply air
temperature required to maintain cooling but is lower than the return air
temperature, the make-up air and exhaust air dampers are 100% open. The
recirculation air damper closes, and the building refrigeration system provides the
portion of cooling load that cannot be provided by outside air intake.

(d) From this it can be seen that it is possible to introduce 100% outside air into a

building during the cooling season.

(e) Formula 6

For example, if out print shop were using 100% outdoor air at 55°F and
40% rh, then the moisture required is

5.19 - (4.89 x 40% rh) = 3.23 gr/ft

3

Therefore, on a 15,000 CFM system, the humidification load will be
15,000 x 3.23 x 60 min/hr

__________________________

7,000 grains/lb

= 415 lbs/hr

(f) In the above examples, the largest humidification load was due to the economizer

cycle at 415 lbs/hr.

(7) Using cooling or refrigeration loads:

(a) As air is cooled, it loses it’s ability to hold moisture. If it is cooled enough, some of

the moisture will condense out. This is known as cooling load. Cooling load
calculations can be important for process applications or refrigeration applications
to product dehydration.

10-10

Page 20
2008-10-01

(b) Formula 7

Assume that during the summer the HVAC system is in the cooling mode. The
air leaving the cooling coil is at 55°F and 90% rh. In order to maintain the
desired 47% rh in the space, moisture must be added using the following
formula:

Desired space 80°F 47% rh= 5.19 gr/ft

3

(Formula 1)

55°F 90% = 4.89 x 0.90 = 4.40 gr/ft

________________________ __________

3

Grains to add = 0.79 gr/ft3

15,000 x 0.79 x 60 min/hr

_________________________

7,000 grains/lb

= 101.57 lbs/hr

(8) In considering Process and Environment, in Tables 5 through 7 you will find conditions

and processes that may affect your calculation and should be addressed.
(a) Table 5 shows the outdoor temperature at which the rh would cause condensation

on the windows to the outside. Should your outdoor conditions make this a
possibility, an outdoor setback sensor may be a solution.

(b) Table 6 describes the moisture gain of various material and if your process or

environment includes a great amount of these materials that are constantly
introduced to the area, its affects must be considered.

(c) Table 7 identifies many recommended indoor conditions for various locations and

processes, these can be of use when deciding what conditions would be most
beneficial in your application.

(d) In Figure 2, you will find the ASHRAE physchrometric chart describing the

enthalpy of dry air and the effects to and from rh in the air.

Table 5. Inside Relative Humidities At Which Moisture Will Condense On Windows

Outside

T emperature

°F °C

Single Windows, Still Air Single Windows, Wind

-50-4599988-50-4543332

-40-401212111010-40-4054443

-30-341614141313-30-3476665

-20 -29 20 18 18 17 16 -20 -29 10 9 9 8 7

-10 -23 25 23 22 21 20 -10 -23 14 13 12 11 10

0 -18 32 29 27 25 24 0 -18 20 18 16 15 13
10-12393633312910-122824222018
20 -7 47 43 40 37 35 20 -7 36 32 30 26 24
30 -1 57 52 50 45 42 30 -1 48 41 38 34 30
40 4 70 63 60 53 50 40 4 62 54 49 43 40

NOTE: Bold areas indicate that moisture will be in the form of frost on windows.

Inside Temperature (°F/°C)

60/

15.5

65/

18.3

70/

21

75/

23.8

80/

26.6

Outside

Temperature

°F °C

Inside Temperature (°F/°C)

60/

15.5

65/

18.3

70/

21

75/

23.8

80/

26.6

10-10

Page 21

2008-10-01

Table 5. Inside Relative Humidities At Which Moisture Will Condense On Windows (cont)

Outside

T emperature

°F °C

Double Windows, Still Air Double Windows, Wind

-50 -45 34 34 34 33 32 -50 -45 23 26 26 26 25

-40 -40 38 38 36 36 35 -40 -40 32 30 30 29 28

-30 -34 42 42 41 40 38 -30 -34 36 34 34 32 31

-20 -29 47 46 46 44 42 -20 -29 41 39 38 35 35

-10 -23 52 50 49 48 46 -10 -23 46 45 42 42 39
0 -18 57 55 55 52 50 0 -18 52 49 47 46 44

10 -12 62 60 59 57 54 10 -12 58 56 53 52 49
20 -7 69 66 63 62 59 20 -7 65 63 59 58 54
30 -1 76 73 71 68 65 30 -1 72 70 66 64 60
40 4 84 80 79 74 71 40 4 80 78 73 70 67

NOTE: Bold areas indicate that moisture will be in the form of frost on windows.

Inside Temperature (°F/°C)

60/

15.5

65/

18.3

70/

21

75/

23.8

80/

26.6

Outside

Temperature

°F °C

Inside Temperature (°F/°C)

60/

15.5

65/

18.3

70/

21

75/

23.8

80/

26.6

Table 6. Regain of Hygroscopic Materials

Industry Materials

Baking Crackers

Flour

White Bread
Leather Sole Oak, Tanned 5.0 8.5 11.2 13.6 16.0 18.3 20.6 24.0 29.2
Printing Paper – Comm. Ledger – 75% Rag

1% Ash
Paper M.F. Newsprint – 24% Ash
Paper White Bond Rag – 1% Ash
Paper Writing – 3% Ash

Textile Cotton – Absorbent

Cotton – American-cloth
Cotton – Sea Isle-roving
Hemp – Manila and Sisal
Jute – Average Grade
Linen – Dried Spun – Yarn
Rayon – Celulose – Acetate – Fibre
Rayon – Cupramonium – Average

Skein
Rayon – Viscose Nitrocel
Silk – Raw Chevennes-Skein
Wool – Australian-Marino-Skein

Tobacco Cigarette 5.4 8.6 11.0 13.3 16.0 19.5 25.0 33.5 50.0
Wood Timber – Average

Glue – Hide

Miscellaneous Charcoal-Steam Activated

Gelatin
Silica Gel
Soap
Starch

NOTE: Moisture content expressed in per cent of dry weight of the substance at various relative humidities –

Temperature 75°F.

10 20 30 40 50 60 70 80 90

2.1

2.8

2.6

4.1

0.5

1.7

3.2

4.2

2.1

3.2

2.4

3.7

3.0

4.2

9.0

4.8

3.7

2.6

3.7

2.5

4.7

2.7

5.2

3.1

5.4

3.6

1.1

0.8

5.7

4.0

5.7

4.0

5.5

3.2

7.0

4.7

3.0

4.4

3.4

4.8

7.1

14.3

0.7

1.6

5.7

9.8

1.9

3.8

2.2

3.8

Relative Humidity - %

3.3

3.9

5.0

5.3

6.5

4.5

5.6

4.7

5.5

6.2

5.2

5.6

7.2

8.5

7.3

1.9

7.9

7.9

8.0

7.6

6.6

3.8

7.6

6.4

8.0

6.2

6.2

6.1

6.5

7.2

18.5

5.9

6.6

8.5

10.2

8.1

2.4

9.2

9.2

8.9

12.8

9.3

7.6

28.3

4.9

17.2

10.0

7.4

3.1

5.0

4.0

4.7

5.2

12.5

4.4

4.6

6.0

6.9

6.5

1.4

6.8

6.8

6.9

8.9

5.9

5.8

22.8

2.8

12.7

5.7

5.2

15.7

10.8

26.2

15.2

6.5

9.9

8.5

6.9

7.2

7.5

8.3

20.8

6.8

7.9

9.9

12.2

8.9

3.0

10.8

10.8

10.2

14.9

11.3

9.0

29.2

6.1

18.6

12.9

8.3

8.3

12.4

11.1

8.1

8.7

8.8

9.9

22.8

8.1

9.5

11.6

14.4

9.8

3.6

12.4

12.4

11.9

17.2

14.0

10.7

30.0

7.6

20.2

16.1

9.2

10.9

15.4

14.5

10.3

10.6

10.8

11.9

24.3

10.0

11.5

13.6

17.1

11.2

4.3

14.2

14.2

14.3

19.9

17.5

11.8

31.1

9.3

21.5

19.8

10.6

14.9

19.1

19.0

13.9

13.2

14.2

25.8

14.3

14.1

15.7

20.2

13.8

5.3

10.0

16.0

18.8

23.4

22.0

12.5

32.7

11.4

22.6

23.8

12.7

10-10

Page 22
2008-10-01