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Mini quiz · Lesson 02
Electrical Diagnostics on HVAC Equipment
Question 01 / 06
An HVAC schematic separates into:
Question 02 / 06
A 45/5 dual capacitor reading 32 µF on the 45 leg means:
Question 03 / 06
Pitted contactor contacts under load cause:
Question 04 / 06
A furnace that lights and shuts off after 5 seconds, retries 3 times, locks out — most likely cause:
Question 05 / 06
Bypassing a rollout switch to keep a furnace running:
Question 06 / 06
CASE: AC unit doesn't start. 240V at disconnect. 24V at the thermostat and condenser. Contactor coil reads 28Ω (spec 25–40Ω). Push the contactor in by hand — compressor and fan start. Release — they stop, contactor doesn't hold. Diagnosis?
0 / 6 answered