The part(s) or condition(s) listed below for the symptom Air handler is not blowing enough are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.
A furnace or air handler air filter should be replaced at least twice a year to ensure good quality air flow throughout the home. An air filter that is clogged with dust and debris will interfere with that air flow and give the impression that the furnace or air handler is not blowing enough.
The run capacitor provides voltage to the blower motor. If the capacitor is defective, the blower motor may not run resulting in the furnace or air handler not blowing enough. To determine if the capacitor has failed, test the capacitor with a multimeter. If the run capacitor is unable to hold and release a charge or is bulging or leaking, replace it.
The capacitor provides voltage to the blower motor. If the capacitor is defective, the blower motor may not run resulting in the furnace or air handler not blowing enough. To determine if the capacitor has failed, test the capacitor with a multimeter. If the capacitor is unable to hold and release a charge or is bulging or leaking, replace it.
Over time, the blower wheel and housing can become clogged with dust and debris. This will restrict the air flow, preventing the furnace or air handler from blowing enough. You can try cleaning the blower wheel with compressed air or with a soft bristle brush. Use caution when trying to clean the blower wheel as the fins are sharp and can be easily damaged. If the blower is damaged it will need to be replaced.
Since the furnace or air handler blower motor is the component that circulates the heated air throughout the home, a defective blower motor will result in the furnace or air handler not blowing enough. You can use a multimeter to test the blower motor for electrical continuity, a continuous electrical path present in the motor, as well as determine if power is reaching the motor. You can also try turning the blower wheel by hand. If the wheel does not turn freely, it's likely the motor bearings have seized and the blower motor will need to be replaced.
Some heat registers have adjustable louvers that allow the air flow to be restricted or shut off entirely. This would be used to cut off the air flow to a room that isn't being used, or to restrict air flow to one room so more air will flow to the other rooms. If there is low air flow, check that the louvers are fully open.
Over time, the blower wheel can become clogged with dust and debris. This will greatly affect the air flow circulating throughout the home. You can try cleaning the blower wheel with compressed air or with a soft bristle brush. Use caution when trying to clean the blower wheel as the fins are sharp and can be easily damaged. A damgaged blower wheel will need to be replaced.
