2011 Duct Leakage Testing in Homes

[@colingenge9999]

I agree with Corey and even though we sell grille mask (duct mask) we also recommend your Vent Caps and even give samples away with each system to encourage testers to get them. Open Range should never be used on a Duct Blaster, which is attached to a flex. The manual doesn't say this specifically but it can be ascertained in another way since you must not run over 100 Pa back pressure (pressure in the flex) and if you run the Duct Blaster near maximum speed the back pressure will be well over 100 Pa. This results in the Duct Blaster reading high by as much as 25%. To get an accurate reading simply use Ring 1 or smaller which will create the same test pressure as Open Range any way. It IS ok to use Open range when the Duct Blaster is connected to the equipment cabinet but even then, you must monitor the pressure in the cabinet to ensure it doesn't go above 100 Pa. Overall we strongly recommend you depressurize the ducts to save time in sealing registers. Results will be the same. When depressurizing, ensure you use the flow conditioner with that piece of foam with 1.5-inch holes in it, and then attach a second tube from this flow conditioner to the other port on Channel B. Never use Open range while depressurizing which doesn't matter much because as mentioned in the previous paragraph, you shouldn't test on Open range anyway. If you don't believe how back pressure can affect your results, pressurize a flex duct that has a flange on the end that has been sealed off with tape. You'll measure a pressure of about 400 Pa and flow rate of 800 CFM even though clearly the flow is zero because the flex is sealed off. This shows the extreme case for sure but does demonstrate the principle of how excessive backpressure will affect your results. None of these issues are a problem when using the Retrotec duct tester. You never need to remember what tubes to hook up or to watch for excessive backpressure. All these functions are automated in the design so you cannot really make a mistake. And, it will give your results in CFM/100 sq ft or any other Code required results.

[@firstreviewer8966]

Great Video! FR

[@coreybreed879]

I'm disappointed to see the omission of the many alternatives to duct mask (disposable plastic tape). I'm obviously partial to VentCapSystems.com, but there's also Duc-Bloc, and even MavCaps. Rigid, reusable, and non-adhesive alternatives produce consistent and professional results that are easily replicated by QA providers. It just makes sense all the way around. The price of tape and it's shipping just went up again at the beginning of 2015 making it an even bigger waste of time, money and resources. If we're really to be the tip of the environmental spear, should we be throwing away wads of plastic after each inspection? Especially when it's not only possible but easier, cheaper and safer to do so?