Nortec`s New NH-EL Humidifier

Nortec’s New NH-EL Humidifier – The Evolution of the Industry’s Most Trusted Electrode Steam Humidifier
The NH-EL is the newest electrode steam humidifier from Nortec.
With forty years of experience and a leader in commercial
humidification, Nortec has developed an all new touch screen
controller that is easy to navigate and contains more information
than ever before.
The NH-EL comes with intuitive touch screen control, integrated BACnet and remote factory diagnosis via Nortec Online
Powered by Help. These are now all standard features.
Also included on all units is a USB port for performance downloads and a SIM card for storage of all
operational information. With the SIM card you no longer have to order replacement boards that in
the past had to be configured at the factory.
The new cabinet launches the new Nortec product brand going forward. The brand will be phased in
with the launch of all new products. We have added an air gap between the mechanical and electrical
sections to ensure there is no heat transferred to the electrical section. Most important in the new
cabinet design is that the unit is now approved for zero side clearance. So, not only is the unit smaller
but most importantly the space required is smaller.
For many years, electrode steam has been the number one selling commercial humidifier. Today it is one of the best
humidification solutions for high performance in green buildings with a thermal efficiency of 98%, excellent water
management and longest lifecycle.
Precise Control
All NH-EL Series Humidifiers have an advanced touch screen controller for precise and
efficient relative humidity control. The humidifier can be controlled by a humidistat, a
relative humidity sensor or be connected to a central Building Management System (BMS)
for maximum control flexibility.
The NH-EL touchscreen controller contains more information than anything seen before.
The touchscreen interface is easy to navigate. The user simply needs to touch what they
want to see on the display. In case of an operational error, the humidifier will make service
adjustments automatically or trigger a shutdown while displaying the function requiring
operator attention.
Economy
Nortec NH-EL humidifiers provide lower initial installation costs for the customer.
Operating costs are also reduced through efficient steam conversion rates and
minimal energy losses due to low hot water drain rates.
NH-EL humidifiers provide clean humidification, reducing air-borne contaminants
and subsequent health-related employee absenteeism. Correct interior humidity
levels in winter maintain comfort at lower temperatures and can reduce heating costs.
NH-EL self-diagnostics confirm optimal operational efficiency and reduce servicing costs.
Installation Flexibility
NH-EL humidifiers offer unprecedented installation flexibility. They can be configured for both small and large
systems. All NH-EL humidifiers are completely packaged for installation ease with installation clearance
significantly improved. In fact, the NH-EL offers zero side clearance which saves wall space in tight installations.
The standard drain water cooling ensures drain water does not exceed 140°F (60°C) to meet local plumbing codes.
Steam distribution is easily accomplished through either the HVAC duct system or into individual areas through
built-on or remote blower packs.
Electrode Steam Technology
The electrode steam system produces clean 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. Solid
mineral scale sinks to the bottom of the cylinder which, when filled with residue, is easily
removed and replaced.
Capacities and Options
With ten (10) unit sizes ranging from 5 pounds per hour through 200 pounds per hour, the NH-EL is certain to meet the
needs of the most difficult design challenges. With the redesigned cabinet resulting in smaller
footprints and reduced installation clearances, the NH-EL should be the most preferred
electrode steam humidifier. Combined with efficient in duct steam distribution manifolds,
short absorption manifolds, insulated steam distribution manifolds, or unit mounted or
remote blower packs, the NH-EL offers the design flexibility demanded in today’s most
stringent applications. Nortec also offers a complete line of accessory controls, electronic and
digital to complement any installation.
For more information on the Nortec NH-EL, please visit www.humidity.com or contact your Michigan Air Products sales
professional. Michigan Air Products maintains a significant inventory of Nortec humidifiers, replacement cylinders,
controls and replacement parts. Nortec’s web based selection software HELP is also available to assist you in your
designs. Registration is easy and can be accessed by visiting www.nortechelp.com.
Smart Shield Solid Chemical Water Treatment offered by Evapco
Evapco, a global leader in heat transfer products, offers innovative water treatment
solutions with the latest break thru in water treatment, Smart Shield. While Evapco
has long been the leader in chemical free water treatment systems, the addition of
Smart Shield truly compliments their water treatment product offering.
Smart Shield is a solid chemistry water treatment system which can be factory
mounted on closed circuit fluid coolers and evaporative condensers, or provided in
remote skid packages for cooling tower applications. Smart Shield avoids the
inherent issues associated with liquid chemicals, including handling, storage,
disposal, spills, etcetera, and is the first and only solid chemical water treatment
engineered to arrive installed on your closed circuit cooler and evaporative
condenser. Evapco did not revolutionize chemical treatment, but they did
revolutionize the release of the chemical through their exclusive polymer coated
tablets. This controlled release solid chemistry system provides the easiest, safest
and most sustainable chemical water treatment system currently available.
Smart shield simplifies the commissioning and ongoing water treatment of your closed circuit cooler or evaporative
condenser. First, the scale and corrosion inhibitor cartridges which are less toxic than liquid equivalents (and easier to
handle) are delivered to your system from a feeder that arrives factory mounted on your equipment riser piping.
Recirculating water flows thru the feeder coming into contact with the inhibitor
cartridge. The inhibitor cartridge contains a solid chemistry
tablet encased in a semi permeable polymer coating. Osmotic
pressure forms in the tablet as it comes into contact with the
water. The tablets polymer coating controls the release rate of
active chemistry over a one month period. Simply replace the
inhibitor cartridges on a monthly basis and chemistry is safely
feed when the spray water system is operating. This innovative solution eliminates the need for
expensive and problematic chemical feed pumps. The Smart Shield package also includes a Bio
Control Feeder which is also factory mounted and piped for control of biological activity in the unit’s water system.
Granular Biocide is delivered by a unique no touch package and easily poured into the storage silo. As recirculating water
flows thru the feeder its integrated membrane technology provides constant release of the biocide and the multi silo
design provides easy and safe control of the biocide residual.
As a complete water treatment package, Smart Shield also includes the premounted factory conductivity controller
which helps maximize water efficiency. The conductivity probe manifold and
automated blow down valve arrived piped and wired to simplify start-up. A
single 120 volt power supply is the only field wiring required to energize the
Smart Shield System. A self-draining piping design is incorporated thru out the
Smart Shield package allowing the feeders, probe manifold and interconnecting
piping to safely drain back to the basin eliminating the need for heat trace or
insulation. Smart Shield is redefining chemical water treatment by providing
innovative controlled release solid chemistry feed system specifically designed
for closed circuit coolers and evaporative condensers.
For more information on Evapco’s Smart Shield, please visit www.smartshield.evapco.com or contact your Michigan Air
Products sales professional. Evapco’s web based selection software EvapSelect is also available to assist you in your
designs. Registration is easy and can be accessed by visiting https://evapselect.evapco.com/evapspec/default.aspx
or by contacting your sales professional.
Smardt Economizer
Magnetic bearing, oil-free chillers are recognized as the highest efficiency chillers in the industry. These
chillers far exceed the guidelines spelled out for chiller efficiency in ASHRAE 90.1. Since no oil is present
in the refrigerant circuit, there is no degradation in performance over time due to oil inhibiting the heat
transfer from the refrigerant to the chilled water.
With only a single moving part in the compressor, the reliability and serviceability of magnetic bearing
chillers has been well documented. When combined with the aforementioned efficiency advantages, a
magnetic bearing, oil-free chiller becomes an attractive alternative to a traditional screw or scroll type
chiller.
Two new innovations from Smardt, thermo siphon free cooling for air cooled chillers and flash
economizers for water cooled chillers, further increase the already best in class efficiency. A description
of each option and the benefits it provides are shown below.
Free Cooling Using Thermo Siphon – Air Cooled Chillers
Thermo siphon utilizes refrigerant migration to provide cooling through bypassing the expansion valve
and without running the compressor. In the Smardt configuration there is no need for extra coils or
fluid coolers. In the case where extra coils are used, the air pressure drop and the water pressure drop
are increased and could offset any savings gained by not running the compressor.
As can be seen in the graphic, changeover is simple, and due to the oil free compressors, the constraint
to maintain oil balance in the refrigerant is eliminated. If you have a dual circuit design, simultaneous
mechanical and free cooling is possible. When used in off peak ambient conditions, thermo siphon can
result in efficiencies as low as .10-.30 kW/ton. This is ideal for applications that have a large number of
hours of operation at low ambient such as data centers and hospitals.
Flash Vessel Economizers – Water Cooled Chillers
A flash vessel economizer eliminates the losses that are inherent in plate & frame economizers, typically
increasing efficiency by 5-7% at full load. The flash vessel economizer uses a different method of cooling
the refrigerant than the plate and frame style. While the plate and frame subcools the liquid by acting
as an evaporator, the flash vessel economizer (Shown below) cools the refrigerant by feeding high
pressure liquid through an expansion device where it flashes off from the receiver pressure to the vessel
pressure.
Smardt has developed the vessel configuration and control sequence to effectively manage multiple
compressors across the full operating range while achieving the highest possible full load efficiency,
which is unique to the industry.
Both of the options described above provide the opportunity for significant increases in efficiency, and
in doing so, offer the opportunity to realize extensive operational savings.
If you would like more information on either of the energy saving options described above or on Smardt
products in general, please contact your Michigan Air sales representative or visit www.smardt.com.
WATER FILTRATION SYSTEMS
A typical 200 ton cooling tower “scrubs” airborne contaminants (dust & pollen) from the atmosphere and
deposits as much as 600 pounds of particulate matter into the condenser cooling water system each
1
year . Poor water filtration may affect performance of your system including:





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Decreases Heat Transfer
Decreases System Flow
Increases Energy Costs
Increases Maintenance Costs
Increases Chemical Treatment
Decreases Equipment Life
Without anti-fouling technology and filtration, systems heat transfer coefficient
2
can decrease on average 29% from peak initial performance .
There are many types of water filtration products. This article will discuss
Centrifugal Separators, Media (sand) Filters, and Disc Filters.
Centrifugal Separators:
A centrifugal separator is a simple mechanical device that uses the principle of
centrifugal force and friction to cause the separation of suspended solids from
liquids. It is a device with no moving parts, has no media and operates
effectively for years without any required maintenance.
The liquid enters on a tangential inlet port (1) where the velocity is increased by an internal acceleration
ring. (2) As the fluid spins through the separation chamber (3) the centrifugal force caused by the
acceleration ring forces the suspended particles to the outer wall of the separation chamber. (4) The
separated particles then slide down the outer wall to the collection chamber while the carrier fluid
undergoes a 270 degree change of direction (5) by the direction plate causing further and more efficient
separation while the vortex breaker (6) allows the suspended particles to settle in the collection chamber.
(7) To remove the solids, a continuous purge can be utilized. An automatic timed purge can be used as
well based on two parameters intervals between purges and purge length.
Centrifugal separators are specific gravity dependent. The specific gravity of earth (silt / soil), is 1.2 to
2.0. Below is an efficiency chart based on several variables including specific gravity and particulate size
(micron). Please note that most particulates in cooling tower water have a specific gravity around 1.6,
and are less than 40 micron, with only 10 to 30% efficiency. Factor in side stream application, and you
are well below the effective operating limits.
Centrifugal Separator
Solids Removal Efficiency
100
90
Efficiency (%)
80
70
Multiple Pass
60
Single Pass
50
40
30
20
10
0
74+
74-40
40-20
74+
74-40
40-20
74+
74-40
40-20
74+
74-40
40-20
Particle Size (microns)
Microns
Microns
Microns
Specific Gravity 7.5
Specific Gravity 3.6
Specific Gravity 2.6
Microns
Specific Gravity 1.7
Most particulate in cooling tower water have a specific gravity in the range of 1.6 and
are less than 40 microns; well below the operating limit of centrifugal separators.
Media (Sand) Filters:
Liquid enters the vessel over the top of the media, flows down and through
the media bed, and out an underdrain system. While the systems can be
manual, automated packages are typically provided. They are selfcleaning, pre-packaged, skid-mounted filtration systems.
As the liquid travels through the media, contaminants are trapped between
the individual beads of media. The media is specifically selected to
provide reliable, consistent levels of particulate removal. As the void
spaces are filled with dirt, the pressure differential across the media
increases. Once the differential pressure reaches a preset level, a
backwash is initiated. The valves reverse themselves, and flow enters
below the media flow upward and out of the vessel, taking trapped
contaminant with it and to the drain. The backwash duration depends on the type of filter in operation.
When the backwash is complete, the valves move back to the forward flow (filtration) mode.
Sand filters are available in numerous configurations including single and multi-vessel units, various
materials of tank construction (fiberglass, stainless steel, carbon steel), high performance depth type, and
other custom options.
Disc Filters:
Developed in the 1960’s to protect drip nozzle irrigation systems, disc
filters operate using a specially designed disc filtration technology. Thin,
color-coded polypropylene discs are diagonally grooved on both sides to
a specific micron size. A series of these discs is then stacked and
compressed on a specially designed spine. When stacked, the groove
on top runs opposite to the groove below, creating a filtration element
with a statistically significant series of valleys and traps for solids. The
stack(s) are enclosed in a corrosion and pressure resistant housing.
During the filtration process, the filtration discs are tightly compressed
together by the spring's power and the differential pressure, thus
providing high filtration efficiency. Filtration occurs while water is
percolating from the peripheral end to the core of the element.
Depending on the micron rating, there are 18 (in 400 micron discs) to 32 (in 20 micron discs) stopping
points in each track, thus creating the unique in-depth filtration.
(Dirty Disc Filter)
(Backwashed Disc Filter)
Disc filters offer several advantages over sand filters including smaller footprint, less backwash, easier
maintenance, more versatile arrangements, and less weight. Click link here, and scroll down webpage
for a video detailing Spin Klin Disc Filter technology. Below is a comparison of sidestream filtration
packages:
Filter Type
Centrifugal
PEP Model
ICS2-TCP-400GPM
Flow Rate of 400 gpm
Dimensions
48”L x 30”W x 72”H
Weight
989 lbs.
Sand
Disc
Screen
BMF-66
TC-3x5x4-BP4-GRN(V)
SAF-4500
86”L x 94”W x 91”H
71”L x 40”W x 89”H
92” x 14” diameter
16,445 lbs
1,019 lbs
353 lbs.
Backwash
0 gallons (with solids
recovery vessel)
1428 gallons
170 gallons
130 gallons
Benefits of Self-cleaning Filters
Over 99% of all filtration systems sold - whether they are centrifugal, sand or disc are self-cleaning skid mounted packages. Given the following benefits, it’s easy to
see why self-cleaning filters are the overwhelming choice.
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Self-cleaning…requires no regular maintenance
Self-cleaning…assures optimal filtration efficiency
Self-cleaning…reduces energy cost
Self-cleaning…extends media life
As filter media accumulates suspended contaminants, the pressure drop across the
filter increases and flow rate decreases. The filter consumes the same power, but
does less work. Self-cleaning extends media life, five to ten year media life is typical.
Actual practice of disciplined, routine maintenance required for manual filters is the
exception, not the rule.
As a consequence, the filter media overloads with
contaminants and thereafter, backwashing is less effective in removing accumulated
solids. Manual cleaning or media replacement is required to remove the accumulated
sludge in the filter.
Cooling Tower Application
Many think that filtration must treat the full system flow. However, it has
been found that for most applications a 5% side stream flow through a
filter is all that is needed to control suspended solids. On condenser water
systems, side stream filters can be installed in two ways. An inline filter
taps the circulation line where water is drawn off, filtered and the clean
water returned to the circulation line. Filter inlet and return lines should be
at least 10 feet apart to avoid registering the same water. The second
method is sump / basin filtration, which filters and returns clean water
directly to the tower sump. Sweeper jets can be
installed in the sump / basin to direct sediment to the
filter inlet to further enhance debris removal. The
sweeper jets can be factory installed at all three
major cooling tower manufacturers.
Legionella
ASHRAE Guideline 12-2000 presents basic treatment recommendations for control and prevention of
Legionella in cooling towers, stating that a principal key to success in Legionella control is system
cleanliness. The September 2000 issue of the ASHRAE Journal states, “Conditions favorable for
amplification of Legionella growth includes water temperature of 77°F to 108°F and presence of scale,
sediment and biofilm”. More simply, maintaining low particle levels reduces the habitat surfaces and
nutrients required for Legionella growth. Removal of particle as small as 5 to 10 microns is required for
effective Legionella control, since these small particles constitute the bulk of particulate surface area for
bacterial colonization and are most easily incorporated in foul and scale.
PEP Filters
PEP Filters (www.pepfilters.com) is an industry leader in the design and manufacture of cooling tower
and process water filtration systems. PEP is a certified manufacturer for ASME code tanks and is UL
listed for the design and assembly of electrical control panels. Based on your specific application needs,
PEP offers water filtration products from 0.5 micron to 500 micron. Please contact Michigan Air Products
for more information.
Flow Rates
Performance
Packaged PEP Filter Skids
Centrifugal Separators
Sand Filters
10 to 5000 gpm
17 to 1006 gpm
71 micron and larger
0.5 to 100 micron
Custom systems are also available.
Disc Filters
50 to 8000 gpm
20 to 400 micron
References:
1. Clive Broadbent, ASHRAE Report 1992 & ASHRAE Handbook.
2. International Journal of Heat and Mass Transfer 41 (1998) 2961-2966.