Frequently Asked Questions
All products except for testers and blowers are shipped via ground. Leak testers must be shipped by truck/freight. Air freight is substantially higher and can easily be 3 to 5 times the cost of ground or truck freight.
Not really but we calibrate the plates with the serial number facing upwards (away from blower outlet). ORIFLOW has determined that orientation is not significant as the differences well within usual variability experienced due to user and equipment tolerances.
|Duct Leakage Testing – RETURN SYSTEM
pressure ductwork”. Even so, you will see specifications that may require return air or exhaust
systems to be leak tested under a vacuum (negative pressure). To perform a proper duct leakage test
under negative pressure using an ORIFLOW duct leakage tester, perform the following steps:
- Use the orifice plate with the recommended leakage range for your job. Use our online
program to help determine which plate(s) you can use with our testers.
- Make sure you have adequate electrical power for the fan. DO NOT OVERLOAD extension
cords. Make sure you use one with the proper gauge.
- Cover all outlets with plastic bags and seal with duct tape.
- Allow all joints and seams that were sealed with duct sealer to cure for at least 24 hours or the
required cure time by the manufacturer, whichever is greater.
- If possible, position the ORIFLOW duct leakage tester in a location where there will be a
straight path from the orifice tube outlet to the location where you will feed air into the system.
- Drill a 3/8″ diameter hole no closer than two or three feet away from the flexible duct to system
- Place the pressure tubing into the previously drilled hole; extend 6 to 12 inches into the duct.
- Seal the tubing penetration joint with putty or tape.
- On the gauge marked “Duct System”, relocate the pressure tubing from the “Supply System”
pressure port to the “Return System” port. Refer to the note on the figure at the bottom of this
- Zero both gauges. Locate adjusting screw on center front of gauge. Use a small slotted
screwdriver. Turning clockwise increases the pressure reading, counter-clockwise decreases
- Close the fan’s inlet damper so the duct system does not get overpressurized by the tester.
- Turn on the tester blower.
- Adjust inlet damper until the reading on the gauge marked “Duct System” is at the system
pressure required for performing the leakage test.
- Once the duct system pressure has been reached and stabilized, note the reading on the
gauge marked “Orifice Tube”. This pressure drop reading will correspond to the amount of air
you’re feeding into the duct system, which is the amount of air that is leaking out.
- Refer to the calibration table that came with your test rig. Find the pressure reading and note
the corresponding leakage rate.
All air leakage testers are shipped by freight(truck) and will be based on location. Requesting a quote will include the freight charge based on the ship-to location.
They do not have a direction or specific orientation. The tubes are flange tap type and are symmetrical. The other tubes you are used to are venturi type tubes and must be installed in specific manner.