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Page 34 of 72 
©Retrotec Inc. 2012 
 

1.

 

Be 15 feet from the building 

2.

 

Terminate in a T 

3.

 

Have 2 pickup points at least 20 feet apart attached to either side of the T 

4.

 

Each point should be covered with a flat plate or box 

These steps will reduce the magnitude and variation of the Baseline pressures your gauge will see.  
After that, time averaging or long Baseline recordings will reduce the impact of these wind pressures.  
Detailed instructions for dealing with fluctuating wind can be found in Troubleshooting 

Error! 

eference source not found.

Summary of Contents for DM-2

Page 1: ...Retrotec Inc Operation Manual Pressure Gauges DM 2 rev 2013 12 02 ...

Page 2: ... This document contains materials protected under International and Federal Copyright Laws This book contains material protected under International and Federal Copyright Laws and Treaties Any unauthorized reprint or use of this material is prohibited No part of this book may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying recording or by an...

Page 3: ...e 18 3 Set the Gauge up with only the Devices and results you use regularly 19 3 1 Setup Menu 19 3 1 1 Full Screen Timeout 20 To change the Full Screen Timeout time period 20 3 1 2 Restore Settings 20 To restore the factory settings 20 3 1 3 Language 21 To change the language 21 3 1 4 Battery Type 21 To select a battery type 21 3 1 5 Display Version Info 21 To view version information 21 3 1 6 n s...

Page 4: ...Check your gauge to see if it needs to be sent to factory for re calibration 36 7 1 Verify your gauge calibration between factory calibrations 36 To perform a tubing check 36 To perform a cross port check 37 To perform a T connection Fan Pressure check 38 To perform a syringe check not as good as the cross channel check 38 8 Use the Gauge with a calibrated fan for air leakage testing 40 8 1 Making...

Page 5: ...ng the Set Pressure key 51 9 10 Keep the Keep Rechargeable Batteries in top shape 52 To charge the batteries 52 9 11 If the Serial Number and Calibration Date are not valid 53 9 12 If the keys on the DM 2 Keypad are not working 53 To fix the keypad if the keypad cable has come loose and keys are not working 53 9 13 Updating Firmware 54 9 13 1 Firmware Changes 54 Table 10 Firmware changes from vers...

Page 6: ...l and updates the information displayed on the screen every second 1 1 Gauge Overview The Retrotec DM 2 mark II gauge has a connections panel a display screen and a keypad The connections panel on the back of the gauge is where all external devices are connected to the DM 2 The display provides information on the current test mode and or setup as well as the device status and measurement values Th...

Page 7: ...nactive as indicated by and Hold which will hold the display and control functions until Hold is turned off Jog will be possible when using Set Speed or Set Pressure 19 n Displays the current value of the slope of the line along which Pressure estimates are extrapolated Can be set between 0 50 and 1 00 A value of 0 65 is suggested for houses 0 60 for ducts and 0 55 for leaky buildings with large h...

Page 8: ...1 1 3 The Keypad The DM 2 keypad provides access to all DM 2 settings and controls Some keys have multiple functions Keys labeled with an arrow and can be used to navigate around the menus to change the current selection and are active as arrows when using the Setup menus or when Jog is being used Pressing and holding a key automatically repeats the keystroke and this feature can be used to scroll...

Page 9: ...rn on the DM 2 first and then plug in the AC power supply to charge the batteries 1 2 3 Operating on Rechargeable batteries It is recommended that the gauge be used on battery power when possible When battery power is insufficient to power the gauge the warning message Battery Too Low will appear on the screen To prolong battery life recharge the batteries only when they reach power displayed on t...

Page 10: ...or Not Rechargeable as needed 3 Press Exit 1 2 6 View the remaining battery power The DM 2 features a battery health indicator displaying the current status of the battery on the main screen The indicator is located in the upper left corner of the display 1 Turn the gauge on by pressing On Off 2 The splash screen is displayed 3 Press Exit to view the main screen The battery power indicator is in t...

Page 11: ...4 Screen Contrast Older model DM 2 gauges include the ability to change the screen contrast in order to improve visibility in different light conditions Newer models have the voltage to the screen regulated so the contrast adjustment is not necessary To change the screen contrast 1 If required insert a small Phillips head screwdriver into the hole on the back marked LCD Contrast 2 Adjust the dial ...

Page 12: ...functions Press Enter to select menu items or to save input values Depending on the Mode in use a volume or area value may be required Volume for Air Changes per hour Area for any of the per Area results Press Enter while the volume or area result is selected to activate data entry for volume or area Enter the appropriate value and press Enter again to save 2 1 4 Device Device refers to the fan or...

Page 13: ...ow across a hole to be used to measure flow through a known hole size like exhaust fan or register CFM L s m3 s m3 h Velocity Air velocity requires pitot tube m s km h ft s ft min mph Velocity Flow Flow from velocity and area of duct CFM L s m3 s m3 h Press Mode to scroll through the results that have been activated in the Setup menu If all modes are activated then pressing Mode will cycle through...

Page 14: ...ume European Separator specify whether to use a comma in place of a period in the numbers displayed Sig Figs Select one of 2 5 3 0 or 3 5 significant figures e g 1134 is displayed as 1135 for 3 5 1130 for 3 0 and 1150 for 2 5 Device Setup enable or disable the use of compatible devices and their associated Range Configurations Mode Setup enable or disable result Modes displayed and specify the uni...

Page 15: ...making any other changes wait for twice the time averaging period to elapse before taking a reading Taking a reading too quickly can lead to recording incorrect results Notice that the Time Avg key is located in the middle of all the arrow keys on the keypad As a user friendly feature while in the Setup Menu the Time Avg key can be used to select menu items just as you would using the Enter key Wh...

Page 16: ...ut the desired speed using the DM 2 keypad Speed is input as a percentage and can be any value from 1 100 3 Press Enter to start the fan The fan will accelerate until the desired speed is achieved 4 Press Exit to stop the fan and cancel the Set Speed or press Set Speed 0 Enter to stop the fan When numerical input is required the Set Speed key functions to input the number eight 8 2 1 13 Jog Hold T...

Page 17: ...ut is required the Jog Hold key functions to input the number nine 9 2 1 14 Pressure The Pressure key asks the DM 2 to calculate a result that would be achieved if the desired test pressure were measured The measured pressure will almost always be at least slightly over or under the exact test pressure making it difficult to report results that are standardised for a specific pressure The Pressure...

Page 18: ...de active when in the appropriate situation do not leave it on for all tests as this may lead to inaccuracies Try the examples below to familiarize yourself with the versatility of this function Example 1 Inaccuracy A 50 Pa building pressure is desired but only 20 Pa can be reached due to severe leakiness In this instance the extrapolated results for flow 50 Pa do not represent the reality of the ...

Page 19: ...o charge the batteries If you change to non rechargeable batteries be sure to set this to Not Rechargeable to avoid damage Display Version Selecting this item shows the Version of the firmware the chipset and the date of last calibration press Exit to get back to the Setup menu n 0 65 Set to 0 65 for house testing 0 60 for ducts and 0 50 for air handler flow measurements Extrapolation factor used ...

Page 20: ...by the Full Screen Timeout setting To change the Full Screen Timeout time period 1 Press Setup to access the Setup menu 2 Press or to select Full Screen Timeout in the list Press Enter 3 Input a time in seconds between 0 120 Press Enter Press Exit The gauge will not display the large format screen if a time period of 0 is entered in the Setup 3 1 2 Restore Settings At any time the factory settings...

Page 21: ...argeable type be sure to go into the Setup menu and choose non rechargeable to prevent the gauge from recharging the batteries and causing damage To select a battery type 1 Press Setup to access the Setup menu 2 Press or to select Battery Type in the list 3 Select the correct battery type for the installed batteries Rechargeable batteries will not be charged when connected to a power supply if Non...

Page 22: ... rather would go through the holes as laminar flow This means that when pressure is quadrupled the flow will also be quadrupled 𝑓𝑙𝑜𝑤 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒1 𝑓𝑙𝑜𝑤 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 4 𝑓𝑙𝑜𝑤 4 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 Houses and ducts have many holes that will have both turbulent and laminar flow going through them Duct holes tend to be slightly larger whereas houses have more prevalent long tiny cracks and therefore tend to have lower n v...

Page 23: ...own that n was 0 7 the flow at 25 should have been 𝐹𝑙𝑜𝑤 25 𝑃𝑎 250 7 100 200 7 𝐹𝑙𝑜𝑤 25 𝑃𝑎 117 𝐶𝐹𝑀 This value is less than 3 off from what it should be If the test pressure was within 1 or 2 Pa of the reference pressure of 25 Pa the Pressure reading would be exact To change the n value 1 Press Setup to access the Setup menu 2 Press or to select n in the list Press Enter 3 Input the new value between...

Page 24: ...nit To calculate Air Change per hour results volume measurements are required The units used for volume can be configured The volume units may be set to cubic feet cu ft or cubic meters m3 To change the Volume units 1 Press Setup to access the Setup menu 2 Press or to select Building Volume Unit in the list 3 Press or to select the desired units 3 1 10 European Separator The European decimal conve...

Page 25: ...gure rounded to either 0 or 5 Table 4 Example values displayed using each of the three significant figure options Significant Figures Base Number 2 5 3 0 3 5 1 034 1 05 1 03 1 035 20 353 20 0 20 4 20 35 147 626 150 148 147 5 4326 72 4350 4330 4325 To change the number of Significant Figures 1 Press Setup to access the Setup menu 2 Press or to select Sig Figs in the list 3 Press or to select 2 5 3 ...

Page 26: ... wheel rim style fan TEC Mn Model 3 240V TEC Mn Model 4 240V TEC Exhaust Fan Flow Meter Exhaust Fan Flow Meter measures air flow through residential exhaust fans between 10 and 124 CFM This Device does not currently work on many DM 2s since the minimum pressure is set to 10 Pa and typical pressures inside the Exhaust fan box are typically 1 to 8 Pa The pressure in Pascals and table from the mfr mu...

Page 27: ...ndividually To enable disable Devices 1 From the main gauge screen press Setup to access the Setup menu 2 Press or to select Device Setup in the list Press Enter 3 Press or to select a device Press or to toggle between Yes or No next to each device Selecting Yes for a device enables that device to be selected on the Main Screen 4 Press Exit to return to the Setup Menu press Exit again to return to...

Page 28: ...apolis True Flow 14 22 Infiltec E3 Open 7 Holes 4 Holes 3 Holes 2 Holes 1 Hole White squares are the most commonly used Ranges and are set as defaults on your gauge Grey settings are turned off or inactive Your gauge may be set up differently by a Vendor of yourself To enable disable Flow Range configurations in Device Setup 1 Enter the Device Setup menu by pressing Enter on Device Setup 2 Select ...

Page 29: ...ic testing needs Use Mode Setup to customize the gauge to enable display of only the specific results that will be used regularly The configuration is permanently saved but can be changed at any time and the new configuration will be permanently saved Once configured pressing the Mode key on the gauge will cycle through only those Modes that are enabled in the Mode Setup menu To configure Modes 1 ...

Page 30: ...ater column in WC and pounds per square foot psf are also available Inches of water column is the easiest to visualize because one inch water column 1 in WC is the amount of pressure required to suck water up a straw to a height of one inch One inch of water column in WC 249 Pa 5 2 psf To measure a pressure 5 Connect a pressure tube to the blue port of the DM 2 6 Press On 7 Place the end of the tu...

Page 31: ...essure 251 5 Pa 4 3 Analog Magnehelic Gauges Retrotec no longer manufactures or sells analog gauges It is recommended that Blower Door systems using analog gauges be upgraded with a digital gauge Retrotec manufactured three types of analog gauges A 60 Pa gauge which displays two ranges 0 Pa to 60 Pa and 20 Pa to 40 Pa A 250 Pa gauge A 500 Pa gauge The E43 Door Fan system included an analog gauge c...

Page 32: ... the analog gauge by tapping the front panel before use as readings will be incorrect if the gauge does not read zero before any tubes are attached Figure 5 Digital and analog gauges display a pressure of 50 2 Pa RetrotecDigital DM 2 left Retrotec s magnehelic gauge system right ...

Page 33: ...ets hotter Reduce fluctuating pressures created by wind There are two types of pressure that wind creates stagnation pressure and velocity pressure Stagnation pressure is felt over a large area in the windward side and for several feet from the building and is a result of the air stacking up due to the wind velocity The wind s velocity is converted to a pressure Stagnation pressures are reduced by...

Page 34: ... point should be covered with a flat plate or box These steps will reduce the magnitude and variation of the Baseline pressures your gauge will see After that time averaging or long Baseline recordings will reduce the impact of these wind pressures Detailed instructions for dealing with fluctuating wind can be found in Troubleshooting Error eference source not found ...

Page 35: ... same fan reduces the uncertainty by 5 in each case Typical uncertainties would be less than half of the values shown however the table exaggerates the uncertainty trend assuming there are errors while testing with different fans gauges and test conditions Table 8 Test result uncertainties vary by changing the number of baseline points the baseline time and Time Averaging for induced pressures Gau...

Page 36: ...cking gauge calibration should be done weekly It only takes a few seconds Connect one tube between Channel A and B If the pressure readings displayed on PrA and PrB match within 2 both that tube and the gauge ports used are OK To perform a tubing check 1 Press Mode until Mode displays PrB to display pressure on both channels 2 Turn Auto Zero Off 3 Press Exit to ensure that there is no Baseline pre...

Page 37: ...f now that you know the tubes are in working order To verify the calibration of a gauge the easiest method is the cross port check shown in Figure 7 which compares the readings of one channel with respect to the other channel If the pressures are equal then it is likely the gauge is accurate because the chance of both channels being out of calibration by the same amount is very small Figure 7 Gaug...

Page 38: ...ing a syringe to create a Fan Pressure This can be done with either one or multiple gauges Although the procedure with a syringe is fairly widely used it is not recommended by Retrotec for the following reasons Requires equipment that most people don t have an analog magnehelic gauge Requires specific syringes 50 and 500 cc It s an awkward procedure Some part of the testing system of tubes and syr...

Page 39: ...Page 39 of 72 Retrotec Inc 2012 Figure 10 Syringe check setup ...

Page 40: ...ded The pressure and hardware connection ports are also clearly labeled on the top of the gauge 8 1 1 Pressure port connections Retrotec has a specially designed connection port that makes a perfect seal and grips the tube well but releases without tearing the tubing after multiple uses This exclusive connector was designed by Retrotec to make contact with the both tube internally and externally w...

Page 41: ...ut will reduce battery life Power Connects the gauge to an external power source using either the AC power adapter or power available from the fan if available To connect the gauge to a Retrotec fan or variable speed fan drive 1 Locate the end of the Umbilical cable this is the bundle of pressure tubing and Control Cable with the shortest length of exposed pressure tubes and Control Cable Plug the...

Page 42: ...The power and Control Cables included in a Retrotec Umbilical cannot be used when using a 3rd party fan Make sure the batteries are fully charged prior to beginning testing 8 2 Control a fan with the gauge to measure pressure and flow After making the necessary connections between the gauge and the fan follow these steps to begin a test To conduct a basic pressure test and ensure your gauge is wor...

Page 43: ...the box are above 8 Pa To create an Exhaust Fan Flow Meter 1 Cut a hole in one side of a medium sized cardboard box where it is only one layer thick and leaving about one inch of cardboard around the edge for stiffness 2 Cut a 2 x 2 square hole in the center of the other side of the box again where the cardboard is only one layer thick This is the flow measuring hole For accuracy the small hole sh...

Page 44: ... less is recommended because higher pressures will decrease the exhaust fan flow rate Box pressures below 3 Pa are less accurate because small fluctuations in pressure will affect the flow a lot Try the same fan with different holes to see the different results ...

Page 45: ...tion pressure set incorrectly 10 25 If the gauge shows a different extrapolation pressure Pressure then the results will be extrapolated to the wrong pressure Improper use of reference tube for pressurization 5 25 Pressurization is seldom used but if the technician is improperly trained they may not set the equipment up properly for this test Time averaging set too high or too low 25 5 to 10 If th...

Page 46: ...ue port of the gauge 2 Set Time Averaging to one second 3 Wave the end of the tube through the air Notice the fluctuations 4 Hold the end of the tube still and swing the middle of the tube Notice the fluctuations Figure 13 The effect of a moving tube on pressure readings 9 2 Check if wind is causing fluctuating pressure Wind blowing across the tip of a tube can cause significant error even if the ...

Page 47: ...tant This will reduce remove the bias caused by constant wind from the measurements but will not help with the fluctuating nature of wind which is the biggest issue Baseline exercise to practice minimizing the effects of wind 1 Use a fan to create an air stream that causes between 2 and 5 Pa pressure 2 Set Time Averaging to one second 3 Place a tube connected to the positive port in the path of th...

Page 48: ...tdoor end connected to two equal length tubes that are placed as far away from the building as possible Place the outdoor pickup tube at least ten feet away from the building s wall and at ground level This will eliminate the stagnation pressure developed when the wind hits the wall If pressure is still too high place a T on the end of the tube and tape it to the middle of a plastic dinner plate o...

Page 49: ...eadings to jump around Figure 15 Errors in pressure reading from a pinched tube It is possible to complete a Blower Door test with a pinched tube It will appear as if the fan is creating a pressure in the building but in fact the results are way off If the gauge begins to display an unusually high or unexplained pressure check the tubing to ensure that it has not been compressed in any way Be care...

Page 50: ...r heats up due to the Sun shining on it and if the tube end is above or below the point where it leaves the enclosure a stack pressure will build up inside the tube that will create a steady pressure that may increase as the tube gets hotter 9 7 Results will be wrong if the Range and Device being used are different than those selected on the gauge If the results just don t make sense check to make...

Page 51: ... pressure before calculating other results 9 9 Pressure can overshoot when using the Set Pressure key When Set Pressure is used to establish 60 Pa for example the fan will overshoot and reach 90 Pa for a few seconds before it settles back to the desired 60 Pa If this is a concern start the fan on Set Speed or set to a lower pressure and then use the Jog key to increase the set point in smaller ste...

Page 52: ...ulate different results depending on which Device is selected 9 10 Keep the Keep Rechargeable Batteries in top shape The DM 2 is designed to recharge NiMH batteries in the gauge eliminating the need to purchase a stand alone battery charger The charging cycle is designed to fully discharge batteries before recharging them This can cause problems if the DM 2 is connected to a power plug for only br...

Page 53: ...ries by interrupting a charge in progress Replace batteries with new AA NiMH batteries after 2 years 9 11 If the Serial Number and Calibration Date are not valid It s recommended to check the serial number and calibration date on the DM 2 regularly If the screen does not display a valid serial number and calibration date please contact Retrotec technical support since your gauge may have switched ...

Page 54: ...depressed 9 13 Updating Firmware The latest firmware is Version 3 01b The gauge must be returned to Retrotec to have the firmware updated 9 13 1 Firmware Changes Table 10 Firmware changes from versions prior to 2 29 to the current version 3 01b Mode Setup units FIRMWARE Version 2 29 Version 2 31 Version 3 01b Pressure Pa in WC psf m3 h Flow CFM L s m3 s m3 h EqLA sq in sq ft cm2 EfLA sq in sq ft c...

Page 55: ...012 Battery Type Not rechargeable Rechargable Display Version Info 0 5 1 00 n 0 5 1 00 Power Down Hour 0 255 Surface Area Unit sq ft m2 Building Volume Unit cu ft m3 European Separator Yes No Sig Figs 3 5 3 0 2 5 Large Display YES ...

Page 56: ...h respect to the green Input B port of the gauge Case 1 Flow Away from Operator If the flow of the fan is away from the operator holding the gauge then the gauge and the operator are on the inlet side of the fan Readings on Channel A in this case will always be negative measuring the induced pressure in the room Since both the fan pressure pickup and the reference for the fan pressure yellow port ...

Page 57: ... the gauge to 3000SR or DU200 tells the gauge not to subtract the room pressure from the PrB value before calculating flow 𝐹𝑙𝑜𝑤 𝑆𝑒𝑙𝑓 𝑅𝑒𝑓𝑒𝑟𝑒𝑛𝑐𝑒𝑑 𝐶𝐹𝑀 𝐹𝑃 𝑅𝑃 𝐾1 𝑁 𝐾 𝐹𝑃 𝐾3 𝐾4 Where FP is the fan pressure from Channel B displayed as PrB RP is the room pressure from Channel A displayed as PrA In all cases The absolute value of FP must be greater than the minimum fan pressure MF shown in Table 11 and grea...

Page 58: ...0 15 E 0 5267 2 7260 0 000 1 0 0 0 1 0 15 Mn Model 3 230 V Open 0 4918 498 9000 0 000 1 0 0 1 0 25 A 0 4889 190 1000 0 000 1 0 0 1 0 25 B 0 4958 60 3500 0 000 1 0 0 1 0 25 C 0 5178 20 4700 0 000 1 0 0 1 0 25 D 0 5022 6 8700 0 000 1 0 0 1 0 15 E 0 5139 2 8170 0 000 1 0 0 1 0 15 Mn Model 4 230 V Open 0 4848 438 7000 0 000 1 0 0 1 0 25 A 0 4952 160 8000 0 000 1 0 0 1 0 25 B 0 4968 48 0800 0 000 1 0 0...

Page 59: ... 0 0000 1 0 10 6 0 5000 24 1250 0 000 1 0 0 0000 1 0 10 2 0 5000 8 2400 0 000 1 0 0 0000 1 0 10 1 0 5000 4 0700 0 000 1 0 0 0000 1 0 10 Retrotec 800 900 18F 0 4690 311 5000 0 000 1 0 0 0000 1 0670 10 18R 0 4800 366 8000 0 000 1 0 0 0000 1 0230 10 9 0 4920 144 5500 0 000 1 0 0 0000 1 0640 10 5 0 4510 97 4100 0 000 1 0 0 0000 1 0480 10 3 0 4700 51 5800 0 000 1 0 0 0000 1 0530 10 1 4 0 4670 30 4200 0...

Page 60: ...sure function based on the values set for n and the Pressure target value in the gauge By using the Pressure function the gauge performs the extrapolation for you if you are in the situation where you need a flow at a test pressure that cannot quite be reached The Pressure values should only be used if the pressure achieved is within 10 Pa of the required test pressure unless you have measured the...

Page 61: ...25 Pa Factors Rather than using the equation in the situation where the 25 Pa test pressure cannot be achieved you can use tables with the factors already calculated and the following procedure Take a flow CFM reading at the pressure achieved and multiply by the Cannot reach 25 Pa factor from Table 14 to get an estimate of the flow that would result at 25 Pa For example if you read 600 CFM at a bu...

Page 62: ...uilding pressure of 25 Pa cannot be reached n value of 0 6 Pressure achieved Cannot reach 25 factor 25 1 00 24 1 02 23 1 05 22 1 08 21 1 11 20 1 14 19 1 18 18 1 22 17 1 26 16 1 31 15 1 36 14 1 42 13 1 48 12 1 55 11 1 64 10 1 73 9 1 85 8 1 98 7 2 15 6 2 35 5 2 63 ...

Page 63: ...ual Flow Exponent n of Enclosure 0 50 0 55 0 60 0 65 0 70 0 75 Achieved Pressure Pa 10 21 4 14 9 7 7 0 0 8 4 17 5 15 16 5 11 3 5 8 0 0 6 2 12 8 20 12 8 8 8 4 5 0 0 4 7 9 6 25 9 9 6 7 3 4 0 0 3 5 7 2 30 7 4 5 0 2 5 0 0 2 6 5 2 35 5 2 3 5 1 8 0 0 1 8 3 6 40 3 3 2 2 1 1 0 0 1 1 2 3 45 1 6 1 0 0 5 0 0 0 5 1 1 50 0 0 0 0 0 0 0 0 0 0 0 0 55 1 4 1 0 0 5 0 0 0 5 0 9 60 2 8 1 8 0 9 0 0 0 9 1 8 65 4 0 2 7 1...

Page 64: ...losure during the test 𝐸𝑟𝑟𝑜𝑟 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝑜𝑓 𝐼𝑛𝑡𝑒𝑟𝑒𝑠𝑡 𝐴𝑐ℎ𝑖𝑒𝑣𝑒𝑑 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 𝐴𝑐𝑡𝑢𝑎𝑙 𝑛 𝐴𝑠𝑠𝑢𝑚𝑒𝑑 𝑛 In the tables the Pressure of Interest is 50Pa and Assumed n is 0 65 or 0 60 The actual flow exponent n for an enclosure can be calculated by measuring building leakage at multiple pressure differences from 10 to 50 Pa and determining the slope of the line Flow C 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒𝑛 The graph of pressure versus flow will ...

Page 65: ... 0 856 0 852 0 848 0 844 0 0 886 0 882 0 878 0 874 0 869 0 865 0 861 0 857 0 854 5 0 896 0 892 0 887 0 883 0 879 0 875 0 871 0 867 0 863 10 0 906 0 901 0 897 0 893 0 888 0 884 0 880 0 876 0 872 15 0 915 0 911 0 906 0 902 0 898 0 894 0 890 0 885 0 881 20 0 925 0 920 0 916 0 912 0 907 0 903 0 899 0 895 0 891 25 0 935 0 930 0 926 0 921 0 917 0 912 0 908 0 904 0 900 30 0 944 0 940 0 935 0 931 0 926 0 ...

Page 66: ... 0 998 1 007 1 017 1 027 1 037 1 047 1 056 1 066 1 076 40 0 993 1 002 1 012 1 022 1 032 1 041 1 051 1 061 1 070 45 0 988 0 997 1 007 1 017 1 026 1 036 1 046 1 055 1 065 50 0 983 0 992 1 002 1 012 1 021 1 031 1 041 1 050 1 060 55 0 978 0 988 0 997 1 007 1 016 1 026 1 036 1 045 1 055 60 0 973 0 983 0 992 1 002 1 011 1 021 1 031 1 040 1 050 65 0 969 0 978 0 988 0 997 1 007 1 016 1 026 1 035 1 045 70 ...

Page 67: ...result would have been if you have put the gauge on the correct Range Use the Flow Conversion Chart for your fan to locate the correct results as follows In this example you were testing with a DU200 DucTester with Range Config on the gauge set to Mid Later you remembered your DucTester actually had the Low Range Ring attached You recorded 33 CFM Find the 33 CFM you recorded under the Mid column f...

Page 68: ...of 72 Retrotec Inc 2012 Watch this quick video on choosing the wrong range and how to recognize it Video image http www youtube com watch v JP1RsL3pm8E list UUr qgIDfAh9wq88Pye4vE8w index 48 feature plpp_video ...

Page 69: ...ll other results in the Mode Setup menu and use or to scroll until Off is displayed to disable all other results 13 Press Exit once to return to the Setup submenu 14 Press to select n 15 Press Enter 16 Use the keypad to set this value to 0 65 17 Press Enter to accept this value 18 Press to select Power Down Hour 19 Leave at 2 hours or set to 0 to turn auto power down off 20 Press to select Surface...

Page 70: ...g air out of it Air is drawn in from outside to replace it showing up as geysers when checked with an air current tester digital gauge A gauge with an electronic pressure sensor and digital display that is capable of reading in tenths of a Pascal Door Fan A test instrument that fits into an open doorway in order to pressurize or depressurize an enclosure It is a calibrated fan capable of measuring...

Page 71: ...he size of an effective leakage area that describes the same air flow rate See ASTM E779 10 eq 5 Fan Pressure The pressure difference between inside the door fan and the surrounding air This pressure can be read as PrB from Channel B on the gauge It is used by the computer to calculate the air flow rate through the Door Fan Fan Top Part on the fan where the fan s tubing Control Cable and power con...

Page 72: ...rol port Output Control port on the gauge to control fan speed labeled Speed Control time averaging Refers to the digital gauge display that must have an adjustable averaging from 1 second to 1 minute for the purpose of averaging fluctuating pressure signals Averaging can be block averages that will update for the length of the average or rolling moving averages that will update continuously by di...

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