How does a blower door test work? Essentially, picture a nylon tarp housing a powerful fan that fits true to form in any doorway. To perform the test, we close all windows and doors (excepting where the blower is attached) and turn off HVAC systems. A blower door test is simple. They install the fan, spin it up to 50 pascals differential pressure (you use cfm for this unit, which is a volume, not a pressure). 50 pascals will be at a certain RPM. Their fan is calibrated to have a lookup between RPM and CFM. 50 pascals might be like 1200 RPM which in your case is apparently 6000 CFM, which Blower door technology has been around since 1977. Now some states have started to adopt the blower door test as a way to measure the efficiency of a home. This test serves to show just how much air is able to make its way into a home, therefore showing how efficient or inefficient your home is at preventing heating and cooling loss. A blower door is a calibrated fan set up in an exterior doorway with a computer attached to it. It sucks the air out of the house until the house is depressurized to 50 pascals of pressure. A pascal is a unit of air pressure. 50 pascals is a standard unit of air pressure we test and compare the total air leakage in every home to. A blend door actuator may have a few different symptoms. The first one is that the heater will blow cold air, even when you have it set to hot. Another symptom is that your A/C will also blow cold air instead of the warm or hot air which is what it’s supposed to do. If a blend door actuator goes bad, there won’t be enough vacuum going to The blower door allows us to find out how much air is moving through the building’s envelope when the house is either pressurization or depressurization. Opening, closing, or sealing the “planned opening” such as doors, windows, ducts and vents in the air control layer will have an effect on the blower door test results. The blower door allows us to find out how much air is moving through the building’s envelope when a house is either pressurized or depressurized. Opening, closing, or sealing the “planned openings” such as doors, windows, ducts, and vents in the air control layer will have an effect on the blower door test results. If the door is left off during the test, the fan will move more air than it would if it had to pull all its air through the return air duct. Therefore, the fan will work harder and the amp draw will be higher than it would be under normal operating conditions. 6. Read the amp draw of the blower motor. Record the reading and compare it to the jzodN.