How to Find the Correct AC Capacitor Size – Dallas TX

Air conditioner capacitors help start the compressor and fan motor in your outdoor AC unit. When a capacitor fails, the air conditioner may stop cooling, make a clicking noise, or the fan may stop spinning.

Homeowners in Dallas often search for how to identify the correct capacitor before replacing the part. This guide explains how to read the capacitor label and determine the correct size.

What Does an AC Capacitor Do?

• The capacitor provides the electrical boost needed to start the compressor and condenser fan motor.
  
  If the capacitor fails, your air conditioner may:
  
  • Make a clicking sound
  • Fail to start
  • Run but not cool properly
  • Have a fan that will not spin

Every capacitor has a label showing the microfarad rating and voltage.

Example label:

45/5 µF 440V

This means:

• 45 microfarads for the compressor

• 5 microfarads for the fan motor

When replacing a capacitor, the microfarad rating must match exactly.

The voltage rating can be the same or higher.

AC System Size      Common Capacitor Size
2 Ton                        35/5 µF
3 Ton                        40/5 µF
4 Ton                        45/5 µF
5 Ton                        55/5 µF

This helps homeowners quickly estimate what capacitor their system may use.

• Common symptoms of a bad capacitor include:
  
  • Air conditioner will not start
  • Outdoor unit makes a clicking sound
  • Fan will not spin
  • System starts then shuts off

Dallas HVAC Parts in Garland carries a large selection of air conditioner capacitors for residential systems.

Bring your old capacitor to the store and our team will help match the correct replacement quickly.

We stock common sizes such as:

• 35/5
• 40/5
• 45/5
• 50/5
• 55/5