ASHRAE Journal - November 2013 - 50
Column EnginEEr's notEbook
Figure 1 Water-side economizers: Non-integrated (left); and integrated (right).
Evaporator
Modulating Condenser
Water Valve for Head
Pressure Control
Condenser
Evaporator
Condenser
Evaporator
Evaporator
Condenser
Condenser
Plate & Frame Heat
Exchanger
Plate & Frame Heat
Exchanger
To
Coils
DOAS Setpoint for Year-Round Cooling Zones
For spaces that require cooling in the winter, don't unnecessarily
heat the ventilation air.
Many times a dedicated outdoor air unit (DOAS)
delivers ventilation air to a space with year-round
cooling demand, such as a data center. That DOAS
unit is sometimes outfitted with a preheat coil and an
unnecessarily high discharge air setpoint in the winter (e.g., 60°F [16°C]). Since energy is being used by
that space's local air-conditioning units to overcome
the cooling load, use the colder winter outdoor air
to assist, rather than hurt, that effort. This will allow
slight cooling energy savings in the winter because
the colder ventilation air helps offset some space cooling load, but more importantly it reduces the energy
use of the preheat coil in the winter. Cost is for programming, and perhaps upgraded duct insulation if
needed for colder air.
This item is not limited to data centers. I've seen
DOAS with heating coils to make the supply air temperature "neutral" even when the spaces served want
cooling. Realistically, 42°F (6°C) air could be delivered in the winter as makeup air without negative
50
ASHRAE JouRnAl
ashrae.org
N ovem ber 2013
From
Coils
consequences, taking the same precautions as for any
cold-air distribution system.
Condenser Water Reset
Don't allow the cooling tower's VFD to slow down tower fans to
the detriment of the chiller.
Some chiller plant operators I visit are quite
proud of how precisely they control the variablefrequency drive (VFD) on a cooling tower fan to
maintain a fixed leaving condenser water temperature and save cooling tower fan energy.
What they don't realize is that this might actually
increase overall chiller plant energy consumption. In many cases, the extra energy spent to run
the cooling tower fans harder, even full speed, is
made back several times over at the chiller, if the
chiller runs more efficiently with cooler condenser
water. Rather than guesses or rules-of-thumb, a
better strategy is to use chiller/tower optimization software available from most DDC vendors, or
monitor overall chiller plant energy4,5 and make
intelligent decisions as to most favorable combination of chiller and tower energy use. Cost is for
ASHRAE Journal - November 2013
Table of Contents for the Digital Edition of ASHRAE Journal - November 2013
Contents
Commentary
Industry News
Letters
Meetings and Shows
Feature Articles
Sequencing & Control of Compressors
Fire Station Renovation
Sewage Plant Heats Village
Standing Columns
Engineer’s Notebook
Building Sciences
Special Supplement
BACnet Today & the Smart Grid
The Performance Gap
Refrigeration Applications
InfoCenter
Energy Modeling
Emerging Technologies
Data Centers
People
Products
Special Products
Geothermal for Big Box Retail
Classified Advertising
Advertisers Index
ASHRAE Journal - November 2013 - Intro
ASHRAE Journal - November 2013 - Cover1
ASHRAE Journal - November 2013 - Cover2
ASHRAE Journal - November 2013 - 1
ASHRAE Journal - November 2013 - 2
ASHRAE Journal - November 2013 - Contents
ASHRAE Journal - November 2013 - Commentary
ASHRAE Journal - November 2013 - 5
ASHRAE Journal - November 2013 - Industry News
ASHRAE Journal - November 2013 - 7
ASHRAE Journal - November 2013 - 8
ASHRAE Journal - November 2013 - 9
ASHRAE Journal - November 2013 - Letters
ASHRAE Journal - November 2013 - 11
ASHRAE Journal - November 2013 - Meetings and Shows
ASHRAE Journal - November 2013 - 13
ASHRAE Journal - November 2013 - Sequencing & Control of Compressors
ASHRAE Journal - November 2013 - 15
ASHRAE Journal - November 2013 - 16
ASHRAE Journal - November 2013 - 17
ASHRAE Journal - November 2013 - 18
ASHRAE Journal - November 2013 - 19
ASHRAE Journal - November 2013 - 20
ASHRAE Journal - November 2013 - 21
ASHRAE Journal - November 2013 - 22
ASHRAE Journal - November 2013 - 23
ASHRAE Journal - November 2013 - 24
ASHRAE Journal - November 2013 - 25
ASHRAE Journal - November 2013 - 26
ASHRAE Journal - November 2013 - 27
ASHRAE Journal - November 2013 - 28
ASHRAE Journal - November 2013 - 29
ASHRAE Journal - November 2013 - Fire Station Renovation
ASHRAE Journal - November 2013 - 31
ASHRAE Journal - November 2013 - 32
ASHRAE Journal - November 2013 - 33
ASHRAE Journal - November 2013 - 34
ASHRAE Journal - November 2013 - 35
ASHRAE Journal - November 2013 - 36
ASHRAE Journal - November 2013 - 37
ASHRAE Journal - November 2013 - 38
ASHRAE Journal - November 2013 - 39
ASHRAE Journal - November 2013 - Sewage Plant Heats Village
ASHRAE Journal - November 2013 - 41
ASHRAE Journal - November 2013 - 42
ASHRAE Journal - November 2013 - 43
ASHRAE Journal - November 2013 - 44
ASHRAE Journal - November 2013 - 45
ASHRAE Journal - November 2013 - 46
ASHRAE Journal - November 2013 - 47
ASHRAE Journal - November 2013 - Engineer’s Notebook
ASHRAE Journal - November 2013 - 49
ASHRAE Journal - November 2013 - 50
ASHRAE Journal - November 2013 - 51
ASHRAE Journal - November 2013 - 52
ASHRAE Journal - November 2013 - 53
ASHRAE Journal - November 2013 - 54
ASHRAE Journal - November 2013 - 55
ASHRAE Journal - November 2013 - Building Sciences
ASHRAE Journal - November 2013 - 57
ASHRAE Journal - November 2013 - 58
ASHRAE Journal - November 2013 - 59
ASHRAE Journal - November 2013 - 60
ASHRAE Journal - November 2013 - 61
ASHRAE Journal - November 2013 - 62
ASHRAE Journal - November 2013 - 63
ASHRAE Journal - November 2013 - 64
ASHRAE Journal - November 2013 - BACnet Today & the Smart Grid
ASHRAE Journal - November 2013 - BCover2
ASHRAE Journal - November 2013 - B1
ASHRAE Journal - November 2013 - B2
ASHRAE Journal - November 2013 - B3
ASHRAE Journal - November 2013 - B4
ASHRAE Journal - November 2013 - B5
ASHRAE Journal - November 2013 - B6
ASHRAE Journal - November 2013 - B7
ASHRAE Journal - November 2013 - B8
ASHRAE Journal - November 2013 - B9
ASHRAE Journal - November 2013 - B10
ASHRAE Journal - November 2013 - B11
ASHRAE Journal - November 2013 - B12
ASHRAE Journal - November 2013 - B13
ASHRAE Journal - November 2013 - B14
ASHRAE Journal - November 2013 - B15
ASHRAE Journal - November 2013 - B16
ASHRAE Journal - November 2013 - B17
ASHRAE Journal - November 2013 - B18
ASHRAE Journal - November 2013 - B19
ASHRAE Journal - November 2013 - B20
ASHRAE Journal - November 2013 - B21
ASHRAE Journal - November 2013 - B22
ASHRAE Journal - November 2013 - B23
ASHRAE Journal - November 2013 - B24
ASHRAE Journal - November 2013 - B25
ASHRAE Journal - November 2013 - B26
ASHRAE Journal - November 2013 - B27
ASHRAE Journal - November 2013 - B28
ASHRAE Journal - November 2013 - B29
ASHRAE Journal - November 2013 - B30
ASHRAE Journal - November 2013 - The Performance Gap
ASHRAE Journal - November 2013 - 66
ASHRAE Journal - November 2013 - 67
ASHRAE Journal - November 2013 - 68
ASHRAE Journal - November 2013 - 69
ASHRAE Journal - November 2013 - 70
ASHRAE Journal - November 2013 - 71
ASHRAE Journal - November 2013 - 72
ASHRAE Journal - November 2013 - Refrigeration Applications
ASHRAE Journal - November 2013 - InfoCenter
ASHRAE Journal - November 2013 - 75
ASHRAE Journal - November 2013 - 76
ASHRAE Journal - November 2013 - 77
ASHRAE Journal - November 2013 - 78
ASHRAE Journal - November 2013 - Energy Modeling
ASHRAE Journal - November 2013 - Emerging Technologies
ASHRAE Journal - November 2013 - 81
ASHRAE Journal - November 2013 - 82
ASHRAE Journal - November 2013 - 83
ASHRAE Journal - November 2013 - Data Centers
ASHRAE Journal - November 2013 - 85
ASHRAE Journal - November 2013 - 86
ASHRAE Journal - November 2013 - People
ASHRAE Journal - November 2013 - Products
ASHRAE Journal - November 2013 - Special Products
ASHRAE Journal - November 2013 - Geothermal for Big Box Retail
ASHRAE Journal - November 2013 - 91
ASHRAE Journal - November 2013 - 92
ASHRAE Journal - November 2013 - 93
ASHRAE Journal - November 2013 - 94
ASHRAE Journal - November 2013 - Classified Advertising
ASHRAE Journal - November 2013 - Advertisers Index
ASHRAE Journal - November 2013 - Cover3
ASHRAE Journal - November 2013 - Cover4
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_MCDEBX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WNYSQY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XATVOD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FJSHSS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CCBZDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XDEFVG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VHGNBL
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WPKBNJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_UUVCDE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTGDEW
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2023
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LKRFXS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AZSOFG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ERCDBH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QWDFRV
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JHGVDF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPUYHG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SREIBM
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LRTGLK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OKRFGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TZSERA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LVRUIX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RPTVYZ
https://www.nxtbook.com/nxtbooks/ashrae/mini_pub_catalog
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XIYTGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2022
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RFGDOB
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PABXNU
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_REMKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PICVBT
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AOYTVW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JQOPLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IOYTBC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SGAJJF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IGHYER
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PDRKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XCODFR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QSLFGO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ILKVNM
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2021
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPDJKD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VJKSRY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDHUTC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JPPKRR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDLTTH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CKLLES
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SLDOX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_HJETUK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OLUHGE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ZERDGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QVMNEO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTPOKE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_BBATRE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_STUBMW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TPEMPE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JNMKDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FBTTPA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WQMMNE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TVBRYN
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2020
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_KTUZMA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ABEDGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201910
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201909
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019septmeber_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019september
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201908
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201907
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201906
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201905
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201904
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019april
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201903
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019march
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201902
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201901
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2019
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018december
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018october
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2018
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201810
https://www.nxtbook.com/nxtbooks/ashrae/ashraeinsights_201806
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201805
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201804
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201803
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201712
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201711
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201710
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201709
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201705
https://www.nxtbook.com/nxtbooks/ashrae/ashrae_meetinginsert_201610
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acrexindia
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer
https://www.nxtbook.com/nxtbooks/amca/2014summer2
https://www.nxtbook.com/nxtbooks/amca/2014summer
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acma_2014summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201311
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201309
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acmasupp_2013fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201305
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201303
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2013winter
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201211
https://www.nxtbook.com/nxtbooks/ashrae/achr_expo_mexico2012
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201209
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v3
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201205
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201203
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012winter
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201111_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201109_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2011summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201105
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201103
https://www.nxtbookmedia.com