Furnace Blower Motor Capacitor Sizing

The capacitor will be located close to the blower motor since it is there to help the blower motor run and have wires coming from it.

Furnace blower motor capacitor sizing.

Here is an example of a furnace blower motor on amazon. A bad or faulty capacitor can exhibit many signs and symptoms. To answer this question the panel door to the furnace will need to be removed. You aproximate sizing of the capacitor is in the range of 4 40 mf and at the motors i have 1 1 2 2 kw the run capacitor is sized between 35 70 uf.

Hvac heating ventilation and air conditioning capacitors store electricity and help compressors and blower motors the systems that distribute hot. If the furnace is receiving power turn up the thermostat and see whether the blower motor starts within the next few minutes. The start up energy of the motor is found either in its documentation or written on the motor itself. Example furnace blower motor on amazon a o.

Where is a furnace capacitor located. Before checking the capacitor make sure the fuse controlling the furnace is flipped to the on position. A furnace usually uses a run capacitor to maintain a relatively constant voltage supply to the blower motor. Smith century dl1056 1 2 hp 1075 rpm 3 speed 115 volts6 5 amps 48 frame sleeve bearing direct drive blower motor.

This chart shows the blower details for a 120 000btu furnace. The difference is more than 100 times is there a calculation error. If you re concerned that your furnace capacitor isn t operating properly you can test it by following a few simple steps. Its capacitor works like a battery and stores the energy needed by the blower to work properly.

Assuming a start up energy of 0 00033 joules you obtain 0 33 divided by 66 1 which equals 5 0 times 10 6 farads. The blower motor in your furnace blows hot air through the ducts and into your home. How to read your capacitor voltage and mfd for a replacement capacitors are rated by the. You can see the listing description the specifications are listed for the motor.

It is difficult to find a 40kbtu furnace that can move 1000 cfm at a reasonably high static. You simply measure the current amps of the motor start winding coming off of the capacitor and multiply it times 2652 on 60hz power 3183 on 50hz power and then divide that number by the voltage you measure across the capacitor. If not the capacitor or the blower motor is not functioning properly. This unit has a variable speed motor that operates in an operating range configuration.

But with a bad capacitor your blower cannot function well and may put your family s comfort at risk.