Service & TroubleshootingQuestion 77 of 110
A contactor in an air-conditioning condenser performs what function?
a.Meters refrigerant
b.Switches line-voltage power to the compressor and fan when energized by the control circuit
c.Drains condensate
d.Adjusts blower speed
Explanation
The contactor is an electrically operated switch whose coil is energized by the low-voltage control circuit, closing contacts that supply line voltage to the compressor and condenser fan. Pitted or welded contacts are a common failure. It is tested for coil continuity and contact condition.
Practice all 110 questions free — no signup required.
Related questions on this topic
- What is the primary function of a run capacitor on a single-phase motor?
- A start capacitor differs from a run capacitor in that it is designed to do what?
- A typical low-voltage control (thermostat) circuit in residential HVAC operates at what voltage?
- If a condenser fan motor fails while the compressor keeps running, what symptom is most likely?
- Low airflow across an evaporator coil during cooling most commonly causes what?
- SEER (or SEER2) is a rating that describes what?
Last reviewed: · editorial process
PrepPass Editorial Team · Verified against California CSLB C-20 Warm-Air HVAC Trade Exam · How we review