If you have a 2 stage furnace (hi fire & lo fire) then the blower will run on lo speed in lo fire & hi speed in hi fire and in AC mode. If it`s a single stage furnace lo speed for heat and hi speed for cooling.
It could be due to a faulty resistor in the blower motor circuit. The resistor regulates the speed of the blower motor, and if it malfunctions, the high speed setting may not work properly. It would be best to have a mechanic inspect and replace the resistor if necessary.
The blower motor resistor module is ruined and need replacement. It can be found from below and behind the glove box. Tt may be hard to see, follow the wires to connection that is mounted to the blower unit by two small hex-head screws. I removed the glove box so I could access it easier than trying to go from the bottom in a confined position.
An ignitor on a furnace works by generating a high voltage electrical current that creates a spark or a hot surface to ignite the gas or oil in the furnace. This ignition process is essential for starting the combustion process that produces heat for the furnace to operate and warm up the space. If the ignitor malfunctions, it can prevent the furnace from starting properly.
If you are being compensated, you are supposed to.
It would all depend on the size of the compressor. If it's a small one(like for an airbrush gun) it might just work, but if it's a compressor to power impact wrenches or similar it'd probably not work.
The blower motor speed resistor is burned out. The high speed function bypasses the resistor. The speed resistor is generally located near to the blower motor.
You may be able to turn up the blower speed but you will probably still not get the appropriate cfm. You may be able to swap out the blower but you may run into problems with fitting the new one in place or the proper sizing of the return and supply duct work.
Blower motor speed resistor is partially burned out.
either the blower control switch or the blower motoer needs replacing
To properly wire the furnace blower motor for safe and efficient operation, follow these steps: Turn off the power to the furnace before starting any work. Identify the wires for the motor, typically labeled as high speed, medium speed, and low speed. Connect the corresponding wires from the motor to the appropriate terminals on the furnace control board. Make sure all connections are secure and properly insulated to prevent any electrical hazards. Test the motor to ensure it is running smoothly and efficiently before closing up the furnace. If you are unsure about the wiring process, it is recommended to consult a professional HVAC technician for assistance.
If the blower works on slower speeds only I would suspect the high speed blower motor relay (under the hood in the power distribution box) or the switch itself. The blower speed resistor is working if all the slower speeds work.
If the one speed it works on is high speed, it is the blower motor speed resisitor that is bad.
If you are saying the blower motor will not work, then check the fuse. If the fuse is not blown, then it is possibly a defective Blower Motor Resistor Pack, blower motor, or blower motor speed control switch, in that order.If you are saying the blower motor will not work, then check the fuse. If the fuse is not blown, then it is possibly a defective Blower Motor Resistor Pack, blower motor, or blower motor speed control switch, in that order.
I would suspect the blower motor speed resister is shot.
If you only have high speed I would blame the blower speed resister. If you have no speeds and the fuse is good, I would blame the blower motor or the switch.
The blower motor speed resistor is burned out.
bad blower resistor