Is A Flow Hood Test Right For You?

If you are here then you are probably like most people wondering what a Flow Hood even is. That’s good because knowledge is half the battle. The other half may be that the HVAC contractor you currently use simply doesn’t provide this testing and you never would have known. But after this you will know what one is and why you might consider one so the next time you are speaking with an HVAC contractor you can initiate the conversation if need be.


What is a Flow Hood Test?

Well we should start by speaking the language of the natives (in this instance the HVAC contractors). This test is more commonly known as an air flow test which will calculate the volume of air that is being pushed out of an individual supply or being sucked in through the return grille. The equipment used is known as an Airflow Capture Hood, or a Balometer.  The test is completely non-invasive to your home so you need not worry of damage or added project work from conducting the test. There are a few very cheap DIY alternatives to quickly test your home such as putting a piece of tissue paper over a return grille and if it holds then you likely have strong enough suction (It doesn’t exactly show if you have too much though) or a trash bag method that involves calculating the time it takes to fill a trash bag at the supply (involves a little math and the accuracy is dependent on when you start and stop the clock in relation to when the bag actually begins filling and when it is completely filled up). So both of these will provide a ball park in my opinion and that might be good enough for you but neither will provide a truly accurate number. Accuracy is key to getting the proper balance in your home so you are not only experiencing comfortable air throughout your home, after all, that is why you purchased the system, but you will also be more efficient which saves you money and decreases unnecessary wear and tear on your equipment.


Why Might I Need One?

Well, long story short, it’s a key player in accurately diagnosing if your homes HVAC system suffers from poor airflow. Hint Hint, most homes do especially when the tip of the iceberg shows that the average household duct leakage is 20-30%. Then you throw in all the additional layers of possible kinks or squished flex duct, degradation of mastic and duct tape, disconnections, etc. All of a sudden, the situation just went code 10-56… wait wrong code, that’s a drunk pedestrian. Any who the situation goes from bad to worse over time. This test will allow you to focus on the appropriate trouble areas instead of aimlessly fixing things that may not need fixed.


Common Problems to Alert You

There are many different signs that your air flow is out of balance. Some examples include:

  • The most obvious is when you physically feel low air velocity coming from a supply
  • Your house takes forever to cool off (Maybe the air coming out of certain supplies actually feels warmer than other supply registers)
  • Temperature imbalances from room to room or floor to floor
  • Back drafting of combustible appliances, especially gas water heaters
  • Doors shut by themselves (Maybe it’s a ghost if you believe in that stuff)
  • Unexplained drafts (As though a window is open when it really isn’t)

Now dont get me wrong, the HVAC system is very complex (more so than one might think) so these examples don’t mean you for certain have an imbalanced system. Kind of like noticing your fuel mileage went down recently – it could be your air filter, spark plugs, oil level/age, tire pressure, tire alignment, brakes are dragging, its summer and you started using your A/C, etc. It’s easy to address that there is a problem; it’s difficult to diagnose the underlying factor(s) causing the problem without testing.


Pushing off the problem and allowing your home to be imbalanced adds strain to the compressor which will more than likely lead to premature failure of the compressor. An actual Air Conditioner unit may look large and complex but there really are only a few big components with the compressor being the main one. You could get a new replacement or refurbished compressor but the labor alone will set you back nearly half a grand. Most would recommend getting a new unit at this point and that’s not cheap. An Airflow Capture Hood is just one of the tools used to properly diagnose the severity of your homes imbalance but it is a simple and effective way to remedy the issue. Also at a much, much lower cost compared to a new compressor or unit. Make sure to ask about this test the next time you’re speaking with a local HVAC contractor. A Performance Contracting minded contractor will be able to point you in the right direction. The worst they can do is give you a quote and you decide if its right, maybe they include it with a FREE consultation but you’ll never know if you never ask.