HVAC Unit 20 FINAL Exam Study Guide 2024.

HVAC Unit 20 FINAL Exam Study Guide 2024. What is the best method to repair a fractional horsepower motor that has a bad bearing? - CORRECT ANSWER Replace the entire motor. A technician needs to check a single-phase compressor. He labels the three terminals "A," "B," and "C" and takes resistance readings of the windings. He reads 10 ohms from "A" to "B," infinity from "B" to "C," and infinity from "C" to "A." Identify the terminals. - CORRECT ANSWER Can not identify terminals: open winding Technician "A" says that a shorted winding will result in in an increased current flow through the winding. Technician "B" says that if a motor is to be replaced, a motor with a lower horsepower rating should always be used. Which of the statements is correct? - CORRECT ANSWER Technician "A" is correct. Technician "B" is incorrect Technician "A" says that while checking the windings of a compressor, a reading of 10 ohms or less from the common terminal to ground indicates that the motor is okay. Technician "B" says that the resistance of the start winding should always be less than the resistance of the start winding. Which of the statements is correct? - CORRECT ANSWER Technician "A" is incorrect. Technician "B" is incorrect. If the motor hums, but does not start, there is a potential problem ___. - CORRECT ANSWER with the starting components (and/or) with an open winding (and/or) with insufficient supply voltage An open winding in an electric motor means that ___. - CORRECT ANSWER a wire in a winding is broken If the resistance of the run winding decreases, the (motor will) ___. - CORRECT ANSWER motor will draw too much current while running