Nuvair PRO HE User manual

Operation Manual
Pro He AlarmTM
Helium Analyzer
Rev 07.16

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 2 www.nuvair.com
If you have any questions on this equipment please contact Technical Support at:
Nuvair
1600 Beacon Place
Oxnard, CA 93033
Phone: [phone]
FAX: [phone]
Email: [e-mail]
Hours: Monday through Friday
8:00 AM to 5:00 PM PST USA
This Operation Manual contains important safety information and should always be
available to those personnel operating this equipment. Read, understand, and retain all
instructions before operating this equipment to prevent injury or equipment damage.
Every effort was made to ensure the accuracy of the information contained within this manual; however,
we retain the right to modify its contents without notice. If you have problems or questions after reading
the manual, stop and call for information.

Pro HeTM Alarm Helium Analyzer
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Table of Contents
1.0Introduction
2.0System Description
2.1Controls
2.2Display
2.3Alarm
2.4Sensor
2.5Batteries
2.6Flow Adapter Cap
3.0Calibration
4.0Operation
4.1Sample Flow Method
4.2Programming Procedures
4.3Alarm Setting
4.4 Full Scale Value Setting
4.5 Auto Off Delay Time Setting
5.0Threshold Alarms
6.0 Powering Off
7.0 Factory Reset
8.0 Maintenance
8.1Analyzer Care
8.2Battery Replacement
9.0Spares and Accessories
9.1Calibration Equipment
9.2110V/220V Charger for Lithium Battery powered Pro He Analyzer
10.0 Troubleshooting
11.0 Relay Output Schematics
Appendix
Analyzer specifications
Charger specifications
Warranty

Pro HeTM Alarm Helium Analyzer
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1.0Introduction
This manual will assist you in the proper set-up, operation and maintenance of the Pro HETM
Helium Analyzer. Be sure to read the entire manual.
Throughout this manual we will use certain words to call your attention to conditions, practices
or techniques that may directly affect your safety. Pay particular attention to information
introduced by the following signal words:
Indicates an imminently hazardous situation, which if not avoided, will result in serious
personal injury or death.
Indicates a potentially hazardous situation, which if not avoided, could result in serious
personal injury or death.
Indicates a potentially hazardous situation, which if not avoided, may result in minor or
moderate injury. It may also be used to alert against unsafe practices.
Notifies people of installation, operation or maintenance information which is important
but not hazard-related.
Warnings Graphics Defined:
Gas Inhalation Skin damage

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 5 www.nuvair.com
2.0System Description
The Pro HETM Helium Analyzer measures helium (He) levels in gases in the range of 0 to 100%
of volume with a.1% resolution. It can be used to measure the He content in all breathing gas
mixes. The Analyzer is designed to verify helium concentration in stored gas cylinders as well
as to monitor continuous flow of gas from a compressor. The Analyzer is a moisture and impact
resistant unit compatible with outdoor and marine environments.
Helium is a colorless, odorless, tasteless gas that will not support life.
Exposure to Helium can lead to unconsciousness and death.
The Analyzer is battery powered or 110/230V and
includes an internally mounted sensor with audible &
visual alarm. The water-resistant case includes a
digital display and controls that are environmentally
sealed
The Analyzer uses a Flow Adapter Cap and Flexible
tubing to deliver sample gas to the Sensor.
Pressurized gases must be regulated to avoid damage
to the analyzer. Use of this Analyzer in a hyperbaric
chamber will void the owner’s warranty.
The Analyzer is self calibrating and ready for use after
powering on. Certified calibration gas should be used
periodically to confirm the accuracy of the analyzer
sensor and electronics are working properly.
This analyzer is designed for use at atmospheric pressures only. It is not designed for
exposures in a hyperbaric chamber. Use of this analyzer in a hyperbaric chamber will
result in incorrect readings and may damage the unit.
Although the Analyzer is a rugged instrument, careless handling or abuse may result in
damage to the Analyzer resulting in inaccurate gas analysis. Inaccurate gas analysis can
lead to serious personal injury or death.
Extreme Helium exposure levels directed at the Analyzer sensor may damage the sensor.
Flow
Adapter Cap
Over Sensor
Face
Water-
Resistant
Case

Pro HeTM Alarm Helium Analyzer
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2.0 Description
Model:
9627
Model:
9628
Model:
He
Model He with rechargeable
Lithium Polymer battery. Only
use Nuvair supplied charger for
this battery.

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 7 www.nuvair.com
2.1.Controls
2.2.Display
2.3.Alarm
The Analyzer includes an audible and visual alarm that is activated when the Sensor reaches
the alarm set points which are user programmed. The alarm will not clear until the
concentration of He drops below user programmed set points.
2.4.Sensor
The Analyzer uses a “Thermal Conductive” Helium sensor to measure He content in gases.
The Sensor is designed for use at atmospheric pressure (0 P.S.I.). The gas mixture to be
analyzed must be regulated to .5-1.0 LPM, and any potential for pressure or vacuum must be
avoided.
2.5.Batteries
The 9627 & 29628 use one 9-volt battery for power. The battery is located inside the Analyzer
and is user-replaceable. These models can be supplied with a 110/230V power supply.
9-volt battery models should have battery removed any time the Analyzer will be stored without
use for extended periods of time.
Screen will blink alternately from “000” to “bAt” at start up when battery is low.
The “He” rechargeable model uses a “110/230V” charger with a Lithium Polymer rechargeable
battery. A fully charged battery should last up to 24 hours. Recharge takes about 4 hours.
DO NOT LEAVE UNIT UNATTENDED WHILE CHARGING and UNPLUG ONCE CHARGED.
Digital
Display
On/Off Button
Low Battery
Indication
Adjust Button
Relay
Output
Program Button
Helium Reading
0 – 100%
In .1 % increments

Pro HeTM Alarm Helium Analyzer
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2.6.Flow Adapter Cap
The Analyzer includes a Flow Adapter Cap with flexible tubing and flow orifice. It attaches to the
Sensor port and is sealed by an o-ring. It can be used to direct the gas sample flow to the
Sensor via one of two methods:
Flow to the sensor needs to be restricted to .5-1liter. Increased flow will create faulty readings.
Nuvair offers flow restrictors to accomplish this task. See appendix.
3.0Calibration
Analyzer calibration must be verified on a weekly basis. Improper calibration may result
in an incorrect reading, exposing the user to dangerous levels of Helium. Exposure to
Helium can lead to unconsciousness and death.
This Analyzer must always be checked against a calibration gas and used with gases
regulated and supplied at atmospheric pressure (0 P.S.I.). Use of gases at higher
pressures may result in incorrect readings and may damage the Analyzer. Incorrect
readings may expose the user to high levels of carbon Dioxide resulting in personal
injury or death.
Checking Calibration or use of the Analyzer with a low battery may result in inaccurate
readings. Inaccurate gas analysis can lead to serious personal injury or death.
If the Analyzer has been subjected to a recent change in ambient temperature, allow it to
stabilize for one hour before checking calibration.
Verify calibration on a weekly basis. Breathing gas applications require the use of a certified He
calibration gas and flow rate of 0.5-1 L/min. The equipment to produce this flow is available
from Nuvair. See Spares and Accessories section. To assure the greatest accuracy for other
applications, use the calibration gas concentration closest to the expected concentration in the
gas being measured.
Should the unit begin to display readings other than the helium percentage of the calibration test
gas, perform a Factory Reset as outlined in Section 7.
Sample Flow Method
Flow is Delivered from
Low Pressure Source
via Flexible Tubing
Direct Flow Method
Flow is Directed to
Flow Orifice on Face
of Flow Adapter Cap
Vent Hole

Pro HeTM Alarm Helium Analyzer
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4.0Operation
Prior to each Analyzer use:
1) Turn unit on (hold on/off for 3 sec) and monitor Display for low battery warning. Replace
battery immediately if warning appears. The display will show “On”, “(version of software)
and then “Att” and then display the current Helevel sensed by the analyzer sensor.
2) Cycle through the current settings of the analyzer.
a. Hold down the “Prog” button for 2 seconds then use the “On/Off” button to cycle
through the two Threshold Alarm Values set, Full Scale Value, Auto shutdown time,
and end.
b. Adjust Alarm values at this time if needed see “4.2”
3) Confirm calibration of Analyzer using “Calibrated Test Gas”
Tip: You can check the battery life and current temperature by holding Adjust button for 3
seconds. The display will alternate from battery life to current temperature (Celsius) twice before
returning the home screen.
Gas, even under moderate pressures, can cause extreme bodily harm. Never allow any
gas stream to be directed at any part of your body.
Never expose the sensor to pressures above atmospheric pressure (0 P.S.I.) or you may
cause damage to the sensor and/or receive false readings. Damaged Sensors will not
provide accurate gas analysis. Inaccurate gas analysis can lead to serious personal
injury or death.
The Pro HeTM can be used to monitor an enclosed space or to analyze a regulated gas sample
flow, the contents of a gas cylinder, or the flow from a regulator:
•If monitoring an enclosed space, simply remove the Flow Adapter Cap to expose the Sensor
face to the atmosphere and allow 15 seconds for the Display reading to stabilize.
•If analyzing a gas flow, the Sample Flow Method is the preferred method. The flow rate
must equal 0.5 to 1 L/min at atmospheric pressure (1 bar). To produce this flow, a Flow
Restrictor and Regulator may be required. Contact Nuvair if you need assistance.
Low Battery
Indication
Ready For
Gas Analyzing

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 10 www.nuvair.com
4.1.Sample Flow Method of Checking Calibration (Preferred)
Nuvair offers He test gas for confirming calibration. See kits in the addendum for
more information.
Testing Gas must contain a known amount of Helium for calibration test to succeed.
Step 1. Attach
Flexible Tubing
to Gas Sample
Flow of 0.5 to 1
L/min
Step 2. Verify
that Gas is
Flowing Out
Holes in Flow
Adapter Cap
Step 3. Allow Display
Reading to Stabilize
Step 4. Record
Reading while Gas is
Flowing
Flow Restrictor/
Regulator
Assembly
1000 PPM He
Calibration Gas
Canister
Nuvair
Calibration Gas
Specs:
CO 10 ppm
He 1000 ppm
Nitrogen Balance

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 11 www.nuvair.com
4.2.Programming Procedures
Keep the “Prog” button pressed for more than two seconds and then release the button.
“Pr” should display for two seconds and then the display will change to AL 1 and alternate
with the 3 digit set value.
It is possible to program:
oAL 1 Low alarm point expressed in ppm of Helium concentration
oAL 2 High alarm point expressed in ppm of Helium concentration
oFSC Value expressed in ppm of Helium concentration corresponding to the current
output full scale value (20mA). 4mA always correspond to 1999 ppm He
concentration.
otOn Time on value- This is the time the analyzer will stay on before auto powering
off.
At the end of the programming procedure the display will show “End” and the instrument
will display the Helium content in the gas mix.
Below are the actual screen views of each of the modes. (*Calib button say as adjust)
Program
Alarm 1
Alarm 2
Full Scale Value
End
Auto Time Off

Pro HeTM Alarm Helium Analyzer
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4.3.Alarm Setting (AL 1 & AL 2)
1.) Press the “Prog” button for more than two seconds and then release the button.
On the display will appear “Pr” for two seconds, then “AL1” will appear and be ready
for changing the value of the alarm percentage. Default is 100% and if either alarm is
set at 100% the alarm will be excluded. After a second the display will show the value
of “AL1” He % current setting.
2.) The blinking digit shows the cursor position.
3.) Press the “Prog” button to increase the value (from 0 to 9)
4.) Press the “Adjust” button to move the cursor to the next digit, the “Adjust” button will
be used to cycle through the rest of the digits.
5.) To complete your entry and save the He % value, press the “On/Off” button. You will
then automatically jump to “AL 2” programming view.
6.) Repeat steps 3 through 5 to modify and save the “AL 2” if desired or leave at 100% to
exclude alarm.
7.) Once programming of “AL 2” is complete you will be in the “FSC” Value Screen and
ready for programming this value. To jump to the end continue to press the “On/Off”
button until the end screen appears.
4.4.Full Scale Value Setting (FSC)
Once the alarms have been set the Pro He Analyzer goes to “FSC” view so that you can
change the analog full scale value. It is not necessary to modify this value which is factory
set at 100. This is the Helium concentration corresponding to 20 mA on the analog output.
4mA is the value at 0% of Helium concentration. This value can be changed in the same
manner as the Alarm settings:
1.) Press the “Prog” button for more than two seconds and then release the button.
On the display will appear “Pr” for two seconds, then “AL 1” will appear. Press the
On/Off button to cycle through the Alarm settings until you reach the “FSC” view. The
“FSC” screen and a 3 digit value will alternate for a few seconds and the Pro He
Analyzer will be ready for adjusting the “FSC” Value.
2.) The blinking digit shows the cursor position.
3.) Press the “Prog” button to increase the value (from 0 to 9) (0-19 on the third value)
4.) Press the “Adjust” button to move the cursor to the next digit, the “Adjust” button will
be used to cycle through the rest of the digits.
5.) To complete your entry and save the FSC value, press the “On/Off” button. You will
then automatically jump to “tOn” programming view.
4.5.Auto Switch Off Delay Time (tOn)
In this setting it is possible to change the auto off delay time of the Analyzer. The display will
show 180 seconds default, We manually change this to 600 seconds before shipping. This
value is changed by the same procedure as the Alarm settings, follow procedure above in
4.3. This setting can be adjusted from 0 to 1999 seconds. To keep the instrument from
turning off the Analyzer time should be set to “000” seconds. To complete your entry and
move to the end screen press the power on/off button when programming is complete.
The analyzer will shut off after the set time value is reached that is programmed into the
analyzer. If you are using the analyzer for continuous blending, set the value to “000” to
prevent the analyzer from shutting off automatically. With the analyzer off inaccurate gas
mixture could take place and lead to a death. Always analyze mixed gas before you dive.

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 13 www.nuvair.com
5.0. Threshold Alarms
The He analyzer will alarm once the gas goes over the alarm set point (AL1 or AL2) .
Once the gas is above the AL1 or AL2 set point the analyzer will go into alarm mode until
the gas value drops below the set point during the gas analyzation. Should the Helium
gas trip the alarms (AL1 or AL2) the instrument will go into alarm mode and will activate
the (optional) relays output (open collector max 100mA) and the internal buzzer. The
display will show the trespassed alarm and the actual measured value. To stop the
audible alarm, press any key. In this event the Pro He Analyzer will remain in alarm mode
until the analyzed value reads below the AL1 and AL2 set points.
The relay output typically is used to shut down the compressor. Nuvair can supply the
necessary components to adapt your compressor to the relay or provide them at the time
of install on a new compressor.
6.0. Powering Off
At the home or gas reading screen, hold down the On/Off button for a couple of seconds.
The Analyzer will display “OFF” and then go blank.
7.0. Factory Reset
In case it is necessary to reset the Pro He Analyzer to the factory settings, or the
displayed Helium Percentage does not correlate with the content of your calibration test
gas, follow this procedure to reset the unit:
1. Power on the unit by holding down the On/Off button until the display turns on.
2. Wait until the display has stabilized and the unit is ready to analyze.
3. Record any alarm levels or Auto Off time that are programmed and retain for later use.
Cycle back to the home screen.
4. Press the On/Off and Adjust buttons at the same time and hold until the display
changes.
5. Release the buttons. The unit should now be reset.
6. Test the Analyzer with calibrated test gas to ensure accuracy. If the analyzer still does
not display an accurate reading, contact Nuvair for repair or replacement of the unit.
7. If the analyzer is now accurate, you may now re-program any alarms and Auto Off
time.
In case of reset, the instrument will delete all the alarms settings and the Auto Off time
value. Before using the instrument after a reset, it may be necessary to program again
the alarm values and the Auto Off value. You should confirm your calibration with a
certified testing gas immediately after a reset before using.

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 14 www.nuvair.com
8.0. Maintenance
8.1. Analyzer Care
Analyzers immersed in liquid or stored in wet environments may not operate properly.
This may result in incorrect readings. Incorrect gas analysis may result in personal
injury or death. The Lithium Polymer battery may present a fire hazard if the battery gets
wet.
Protect the analyzer from excessive shock and impact. Excessive shock and impact may
result in incorrect readings. Incorrect gas analysis may result in personal injury or
death.
Protect the analyzer from exposure to hyperbaric environments. Exposure to hyperbaric
environments may result in incorrect readings. Incorrect gas analysis may result in
personal injury or death.
8.1. Analyzer Care
•Do not clean Analyzer with anything other than a damp soft cloth.
•Do not immerse in liquid, leave unprotected outside, or store in a wet environment.
•Protect Analyzer from excessive shock and impact.
•Protect Analyzer from excessive exposure to sunlight and extreme temperatures.
•Do not use the Analyzer in a hyperbaric environment.

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 15 www.nuvair.com
8.2. Battery Replacement
Be sure to dispose of spent or damaged Battery properly, according to local regulations.
The following pictures illustrate the steps required to replace the batteries in the Analyzer.
“He” Model: Remove four nuts and pull out aluminum plate. Under this plate is the Lithium
Polymer battery. Contact Nuvair for a replacement battery.
Step 1. Remove
Screws
Step 2. Remove
Back Cover
Step 3.
Remove &
Replace Old
Battery
Step 5.
Reinstall
Screws
Step 4. Replace
Back Cover -
Do Not Pinch
Wires
Step 6. Turn
Analyzer On
Step 7.
Perform
Calibration
4 - Nuts must be
removed to
access battery
Battery

Pro HeTM Alarm Helium Analyzer
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8.3.Sensor Replacement
Should the sensor become faulty, contact Nuvair for repair or replacement.
Replace sensor when the Helium analyzer is unable to correctly analyze Helium gas. The
use of an exhausted sensor may cause dangerous analysis and lead to death. Wrong
Helium analysis may lead to death. Always contact “NUVAIR” for sensor replacement. Do
not use any other helium sensor brands for replacement.
9.0Spares
9.1.Calibration Equipment
Calibration check requires certified He calibration gas to
be delivered at a specific flow rate and pressure.
A variety of calibration gas canisters are available from
Nuvair, with compatible Flow Restrictor/ Regulator
assemblies to regulate the gas.
9.2.110V/230V Charger for Lithium Battery powered Pro He Analyzer
VERY IMPORTANT YOU ONLY USE NUVAIR SUPPLIED MODEL: H00740003-XX-W1 USING
ANY OTHER CHARGER COULD CAUSE A FIRE.
Flow Restrictor/
Regulator
Assembly
Nuvair
Calibration Gas
Specs:
CO 10 ppm
He 1000 ppm
Nitrogen Balance

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 17 www.nuvair.com
10.0 Troubleshooting
SYMPTOM REASON SOLUTION
Battery symbol Low Battery Change the battery
No display
Switched off
Bad connection
Low Battery
Switch on
Check display/ battery connection
Change the battery
Reading erratic
Pressure on sensor
Radio transmission
Sensor old or faulty
Condensation on sensor.
Check flow
Move unit away
Return to Dealer
Dry in air
Display segments missing Display faulty Return to dealer
Reading drifts Rapid temperature change Stabilize temperature & recalibrate

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 18 www.nuvair.com
12.0 Relay Output Schematics
4-20mA Connections: The relay output uses a special “Mini Jack” plug that can be
purchased separately from Nuvair. Insert the plug into the output jack. Connections diagram
below for additional wiring.
The plug should be connected or disconnected when the instrument is switched off, or
the instrument will automatically switch off.
Open Collector Connections:

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 19 www.nuvair.com
Appendix
Analyzer Specifications
Resolution: 0 – 100% Helium in air or nitrogen or oxygen
Alarm Set Point: What ever % desired of He
Display Accuracy: +/- 2%
Sensor Type: Thermal Conductive Technology
Expected Sensor Life, Room Air: 2 Years
Power: 9 Volt Alk/7.4V Li, or optional 110/230v electric
Battery Life: 3 hrs alkaline battery, 6 hrs+ with Lithium battery
Response Time: Less than 10 Seconds to 90% of Final Value
Stabilization Time: 10 Minutes Max Accuracy
Operating Temperature: 41 to 104°F (5 to 40°C)- Will work outside this range
with decreased accuracy.
Storage Temperature: 5 to 122°F (-15 to 50°C)
Operating Pressure: Not to Exceed 1 Atmosphere Absolute (0 P.S.I.)
Humidity: 0-90% Non Condensing.
Don’t allow moisture to build up on the sensing surface.
Note: All specifications are at ambient / sea level, 77°F / 25°C and subject to change without notice
Charger Specifications for Lithium Polymer rechargeable battery Models
Features:
•110V-240V AC input for worldwide power support
•Constant charging current for faster charging
•Stabilized output, low ripple
•Safety Protection:
•Over Voltage Protection
•Short Circuit Protection
•Output reverse input protection
•The charger will cut off automatically if battery is
fully charged (1/10C) and indicated by LED
In charging mode RED LED
Battery Full GREEN LED
Spercifications:
Input: AC 100-240V 50-60Hz
Output: DC 8.1V
Charging Current: 300mA
WARNING:
•Charge only Nuvair 7.4V Li-ion rechargeable battery pack with this charger
•Don’t expose the product to rain or humidity to prevent from electric shock
•It is normal for the product to get slightly warm when in use
•Keep out of reach of children
•Don’t touch any part of the product during charging to prevent electric shock.

Pro HeTM Alarm Helium Analyzer
NUVAIR Page 20 www.nuvair.com
NUVAIR Pro HeTM Warranty
NUVAIR extends a limited warranty, which warrants the Pro HeTM to be free from defects in materials
and workmanship under normal use and service for a limited period. The Pro He is warranted according
to the pro-rated terms as set forth below. This warranty is not transferable.
NUVAIR will, at it’s discretion and according to the terms as set forth within, replace or repair any
materials which fail under normal use and service and do not exhibit any signs of improper maintenance,
misuse, accident, alteration, weather damage, tampering, or use for any other than the intended purpose.
Determination of failure is the responsibility of NUVAIR, which will work together with the customer to
adequately address warranty issues. When any materials are repaired or replaced during the warranty
period, they are warranted only for the remainder of the original warranty period. This warranty shall be
void and NUVAIR shall have no responsibility to repair or replace damaged materials resulting directly or
indirectly from the use of repair or replacement parts not approved by NUVAIR.
Terms:
NUVAIR warrants the Pro He to be free from defects in material and workmanship for a period of twelve
(12) months from date of purchase. The warranty covers parts and labor.
A warranty registration card, supplied with system documentation, must be filled out and submitted to
NUVAIR for the warranty to be registered. If the warranty registration card is not received within ten (10)
days of purchase, the warranty will begin with the date of manufacture by NUVAIR.
Maintenance Items:
Any materials which are consumed, or otherwise rendered not warrantable due to processes applied to
them, are considered expendable and are not covered under the terms of this policy. This includes
batteries.
Return Policy:
Application for warranty service can be made by contacting NUVAIR during regular business hours and
requesting a Return Material Authorization number. Materials that are found to be defective must be
shipped, freight pre-paid, to the NUVAIR office in Oxnard, California. Upon inspection and determination
of failure, NUVAIR shall exercise its options under the terms of this policy. Warranty serviced materials
will be returned to the customer via NUVAIR’s preferred shipping method, at NUVAIR’s expense. Any
expedited return shipping arrangements to be made at customer’s expense must be specified in
advance.
Limitation of Warranty and Liability:
Repair, replacement or refund in the manner and within the time provided shall constitute NUVAIR’S sole
liability and the Purchaser’s exclusive remedy resulting from any nonconformity or defect. NUVAIR shall
not in any event be liable for any damages, whether based on contract, warranty, negligence, strict
liability or otherwise, including without limitation any consequential, incidental or special damages, arising
with respect to the equipment or its failure to operate, even if NUVAIR has been advised of the possibility
thereof. NUVAIR makes no other warranty or representation of any kind, except that of title, and all other
warranties, express or implied, including warranties of merchantability and fitness for a particular purpose,
are hereby expressly disclaimed. No salesman or other representative of NUVAIR has authority to make
any warranties.