A faulty condenser fan motor on an air conditioning system will cause these symptoms...

• A. Low suction pressure and low discharge pressure
• B. High suction pressure and low discharge pressure
• C. High suction pressure and high discharge pressure
• D. Low suction pressure and high discharge pressure

Answer: (C)

When a condenser fan isn’t working, heat can’t be rejected from the high‑pressure side efficiently. The condenser runs hotter and at a higher pressure because the refrigerant isn’t condensing properly. To push this hotter, higher‑pressure refrigerant through the condenser, the compressor has to work harder, which raises the discharge (high‑side) pressure. Because the entire cycle shifts to a higher operating pressure, the evaporator side also ends up at a higher pressure, so the suction (low‑side) pressure increases as well. In short, a cooling deficiency on the condenser side pushes both sides of the system to higher pressures, so you’ll see high suction and high discharge pressures.