subject: How To Do the Garbage Bag Airflow Test [print this page] How To Do the Garbage Bag Airflow Test How To Do the Garbage Bag Airflow Test
Nothing beats the coziness of your own home especially during those cold, winter nights. However when you're freezing in it despite having a furnace then there's a problem. One way tocheck if poor air flow is the problem is to use the garbage bag airflow test.
Poor air flow is one of the most common problems with heating and cooling equipment.This problem makes your heating and cooling equipment work like inefficient outdated models and this can waste a lot of your momey.The two most common reasons for poor air flow: inadequate duct sizing and a dirty return air filter.
Inadequate Duct Sizing
Inadequate duct sizing is usuallycaused by a poor installation by a contractor who might possibly not have the qualifications to do proper sizing. It is acommon problem that a home owner may battle for years to come and could cost a lot of money over the life of the equipment. It is veryimportant to get references before selecting a contractor.
A Dirty Return Air Filter
A dirty return air filter is the easiest problem to solve. Simply change your return air conditioning filtermore often or use a filter that does notlimit air flow. This simple change can lead to huge savings.
Perform the Garbage Bag Air flow Test
Garbage bag airflow test is one of the easiest and cheapest methods to determine the air flow of your furnace registers, bathroom exhaust fan or clothes dryer exhaust.It's an important test to run to find out why your furnace isn't supplying enough warm air in your room.This test is also useful if you want to see whether your newly purchased exhaust is working properly. The same goes when you're having major renovations in your home that call for a change in your heating or cooling systems. It's the cheapest way to check your furnace register and exhaust fans performance as it only requires a garbage bag.The garbage bag airflow test could not exactly measure the air flow but doing it is way better than not to conduct any test at all.
Here's how to do the garbage bag airflow test:
1. Secure the mouth of your garbage bag by using a tape into a bent coat hanger or a cardboard to keep it open.
2. Make sure you deflate the bag by crushing it flat.
3. Place the open part of the bag (mouth) over the furnace register or exhaust hood.
4. Using a stopwatch or any gadget track the number of seconds it requires for the bag to completely inflate.
If you're utilizing a small garbage bag that measures 66 x 91 cm, you can usethe data below to determine the airflow:
Inflation time = Airflow
*2 seconds = 35L/s (75 cfm)
*4 seconds = 20 L/s (40 cfm)
*10 seconds = 10 L/s (20 cfm)
However, if you're using a bigger garbage bag that measures 79 x 119 cm, make use of this data:
Inflation time = Airlfow
*2 seconds = 100 L/s (210 cfm)
*4 seconds = 50 L/s (105 cfm)
*6 seconds = 35 L/s (75 cfm)
*10 seconds = 20 L/s (40 cfm)
If you have measured an airflow that isless than 10 L/s, then your furnace is providing you with just a small amount of heat. If this is the case you may need to do further investigation to find out why the heat is not going through.
Another test that is associated with this garbage bag airflow test is the deflation test. This is not as accurate as the inflation test described above but doing it won't cost you anything. Deflation test measures the amount of air going out. This is done by holding the inflated garbage bag over the exhaust grill while counting the number of seconds it takes for the bag to be fully deflated. However, this test isn't a reliable source to determine low airflow. The amount of air that goes out can be determined by simply adding a second on the inflation time. Thus, 35 L/s would take 3 seconds, 20 L/s for 5 seconds, and so on.
