Oriflow Cobra User manual

© Copyright 2017 ORIFLOW LLC
Operating Instructions for
Cobra and Lynx
Duct Leakage Testers
(Metric)

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
1
Table of Contents
Introduction
Introduction ……………………………………….…….. 2
Safety Precautions
Safety Precautions ………………………………….…. 2
Prior to Testing
Are You Using the Correct Tester? …………………… 3
System Preparation …………………….………………. 3
Power Requirements ………………………………….... 3
Extension Cord Requirements ……………………….... 4
Flex-Duct Length ………………………………………... 4
Determining Maximum Allowable Leakage ….……..... 4
Determining Which Orifice Plate to Use …………….... 5 - 6
Duct Leakage Test Setup and Procedure
Install Orifice Plate and Upper Tube Section ………… 7 - 8
Connect Flexible Duct to Orifice Tube ………………... 9
Connect Flexible Duct to Duct System ……………….. 9
System Test Pressure Connection ……………………. 10
Duct Leakage Test Setup (SUPPLY) …………………. 11
Duct Leakage Test Setup (RETURN/EXHAUST) …… 12
Zeroing Pressure Gauges ……………………………… 13
Avoiding Over-Pressurization ………………………….. 14
Obtaining System Test Pressure ……………………… 15
Determining Leakage Rate……………………………… 15 – 17
Troubleshooting
Can’t obtain system test pressure ……………………… 17
Zero reading on “DUCT SYSTEM” gauge ………….... 18
Zero reading on “ORIFICE TUBE” gauge …………….. 19
“ORIFICE TUBE” gauge reading maxed out………...... 19

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Introduction
These operating instructions are for ORIFLOW models COBRA and LYNX air
leakage testers. Take pride in knowing that you have purchased the best air leakage
tester on the market. It is no secret that Oriflow manufactures the highest quality
testers, and has unparalleled customer service and technical support.
The orifice plates available for your duct leakage tester are constructed from laser-
cut 1.6 mm stainless steel and do not require recalibration for 5 years. Note the
authority having jurisdiction may override this requirement, and if so, Oriflow has
reasonable rates for re-calibrating orifice plates manufactured by Oriflow.
Safety Precautions
Before operating your tester, read the following safety precautions:
DO NOT operate the tester in the rain,
DO NOT operate the tester while it is near or in water,
DO NOT operate the tester with a damaged electrical cord or plug,
DO NOT remove the inlet safety screen,
DO NOT touch the blower wheel when the unit is plugged in,
DO NOT look into the discharge end of the tester when the unit is plugged in,
DO NOT use the tester as a ladder or step stool,
DO NOT allow children near the tester,
DO use an extension cord of the proper gauge (see Table 2),
DO use the proper voltage and line frequency listed on the motor nameplate,
DO lock the caster when the tester is positioned horizontally,
DO use the tester on level ground,
DO secure the tester when transporting it,
DO wear proper hearing protection, safety glasses and work gloves,
DO seek assistance when lifting the tester (e.g., loading onto truck, going up
or down stairs).

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Prior to Testing
Are you Using the Correct Tester?
See Table 1 for the maximum capacity for each duct tester when using the largest
orifice plate.
Table 1 – Duct Leakage Tester Capacities
MaximumLeakageCapacity(L/s)*
Model250Pa500Pa.1000Pa1500Pa2000Pa.2500Pa3000Pa3500Pa4000Pa.
Lynx260L/s255L/s215L/s110L/s—————
Cobra310L/s305L/s285L/s220L/s95L/s————
Panther635L/s625L/s570L/s505L/s415L/s290L/s125L/s——
Rhino770L/s730L/s 670L/s630L/s560L/s490L/s420L/s310L/s225L/s
*–Usingthelargestsizedorificeavailableforthemodellisted.
System Preparation
Cap off all ends of system using clear plastic and duct tape or sheetmetal duct end
caps. Make sure you test the part of the duct system that leakage testing is required.
Usually, this is from the system fan up to, but not including, the VAV boxes (terminal
units). Refer to the engineer's specifications and all applicable codes and test
standards.
Power Requirements
Do you have an adequate power supply for your tester (see Table 2)?
Table 2 – Tester Amp Draw
Tester Model Voltage Flow Control
Option Full Load Amps
Lynx 115 Slide Gate 12.7
Cobra 115 Slide Gate 12.8
Cobra 115 VFD 14.0
Cobra 230 Slide Gate 6.4
Cobra 230 VFD 8.0

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Extension Cord Requirements
If you need an extension cord, is it the proper gauge? See Table 3 below for
extension cord requirements.
Table 3 – Required Extension Cord Wire Gauge
Tester Model Flow Control
Option Voltage Extension Cord
Length (meters) Wire Gauge
Lynx or Cobra Slide Gate 115 3 to 15 14
15 to 30 12
Cobra Slide Gate 230 3 to 50 14
15 to 30 14
Cobra VFD 115 3 to 50 14
15 to 30 12
Cobra VFD 230 3 to 50 14
15 to 30 14
Flex-Duct Length
Make sure you have enough flexible-duct with your tester for the job. Each tester
includes 3.8 m, which is enough for most applications. Extra lengths of flexible-duct
are available at www.oriflow.com/products.
Determining Maximum Allowable Leakage
To determine the maximum allowable leakage for the project, use ORIFLOW’s free
online programs to make these calculations (www.oriflow.com/programs).
In the U.S., calculations are done for either of the two typical specifications:
1. Percentage of system flow, or
2. SMACNA Leakage Class.
In Europe, Australia and other countries outside of the U.S., the following
specification is commonly used:
1. Pressure Classification (Class A, B, C or D)
If the specification uses SMACNA Leakage Class or Pressure Class, you will need to
calculate the total duct system surface area.
Oriflow has FREE Adobe forms available that will calculate duct surface area given
the duct shape, dimensions and length (www.oriflow.com/freeform). These forms
also calculate Leakage Factor, allowable leakage and Pass/Fail criteria among other
calculations.

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Determining Which Orifice Plate to Use
After determining the allowable leakage at the system test pressure, refer to the
following tables for the capacities of each orifice plate available for the Cobra and
Lynx model testers. The proper plate is the one where the specified allowable
leakage falls between the minimum and maximum leakage at the system static
pressure.
For example, if you are testing a system at 1000 Pa pressure and the maximum
allowable leakage is 165 L/s, you will need a 76 mm orifice plate if using the Cobra
tester (see Table 6) or a 102 mm plate if using the Lynx tester (Table 7).
Table 4 – Tester Capacities using the 25 mm Orifice Plate
System Static
Pressure
(Pa)
Minimum
Leakage*
(L/s)
COBRA Tester
Maximum
Leakage
(L/s)
LYNX Tester
Maximum
Leakage (L/s)
250
4.2 18 15
500 4.2 17 30
750 4.2 16 14
1000 4.2 14 13
1250 4.2 12 8
1500 4.2 10 5
2000 4.2 4.2 --
Table 5 – Tester Capacities using the 51 mm Orifice Plate
System Static
Pressure
(Pa)
Minimum
Leakage*
(L/s)
COBRA Tester
Maximum
Leakage
(L/s)
LYNX Tester
Maximum
Leakage (L/s)
250
16 73 61
500 16 71 59
750 16 68 57
1000 16 63 50
1250 16 59 40
1500 16 47 24
2000 16 17 --

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Determining Which Orifice Plate to Use (continued)
Table 6 – Tester Capacities using the 76 mm Orifice Plate
System Static
Pressure
(Pa)
Minimum
Leakage*
(L/s)
COBRA Tester
Maximum
Leakage
(L/s)
LYNX Tester
Maximum
Leakage (L/s)
250
39 196 165
500 39 193 160
750 39 184 151
1000 39 177 135
1250 39 160 109
1500 39 137 66
2000 39 54 --
Table 7 – Tester Capacities using the 102 mm Orifice Plate
System Static
Pressure
(Pa)
Minimum
Leakage*
(L/s)
COBRA Tester
Maximum
Leakage
(L/s)
LYNX Tester
Maximum
Leakage (L/s)
250
83 309 260
500 83 304 255
750 83 297 241
1000 83 283 215
1250 83 257 172
1500 83 219 109
2000 83 94 --

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Install Orifice Plate and Upper Tube Section
The orifice plate that was determined from the previous section should now be
installed with the serial number facing upwards so the corresponding calibration
certificate may be referenced after installation. Refer to Figures 1 through 4.
Figure 1 – Install Orifice Plate and then Rotate Clockwise
Figure 2 – Rotate Orifice Plate Clockwise until it Locks in Place

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Install Orifice Plate and Upper Tube Section (continued)
After the orifice plate is locked in place, place the upper tube section over the
bolt/wing nut set, rotate clockwise, and tighten wing nuts (Figures 3 and 4).
Figure 3 – Install Upper Tube Section and Rotate Clockwise
Figure 4 – Tighten Wing Nuts after Rotation

© Copyright 2018 ORIFLOW LLC Rev: 03/2018
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Connect Flexible Duct to Orifice Tube
See Figure 5 below for securing one end of the flexible duct to the orifice tube. Note
that the worm-gear clamp should be slid over the flex-duct before connecting it to
the orifice tube. Slide the flexible duct so that it overlaps the orifice tube 50 to 75 mm,
and tighten clamp using a 8 mm nut driver.
Figure 5 – Installing Flex-Duct on Tube
Connect Flex-Duct to Duct System
Connect the 152 mm end of the flex-duct to the duct system. Find a convenient
location in the duct system where the tester has easy access. Make sure the
connection is a sturdy, sealed tight connection. You don’t want to create a leaky
connection thereby adding to the system leakage.
Figure 6 – Connection to Duct System