Question 89Refrigeration & AC - QMED

70% to pass

How does a refrigeration solenoid valve differ from a modulating valve?

ABoth valves operate in exactly the same manner, only the manufacturer's terminology is the differentiating factor.

BA solenoid valve can only be installed in liquid lines.

CSolenoid valves are only used in low voltage refrigeration control systems, while modulation valves are used in high voltage applications.

DA liquid line solenoid valve is either completely opened or closed, whereas a modulation valve is infinitely positioned according to the strength of the applied electrical signal.

AI Explanation

The correct answer is D. A liquid line solenoid valve is either completely opened or closed, whereas a modulation valve is infinitely positioned according to the strength of the applied electrical signal. Solenoid valves are binary devices that provide on/off control, while modulation valves can vary the flow rate in proportion to the control input. This makes modulation valves more suitable for fine-tuning and precise temperature control compared to simple on/off solenoid valves. The other options are incorrect. Option A is incorrect because the two valve types operate differently. Option B is incorrect because solenoid valves can be installed in both liquid and gas lines. Option C is incorrect because solenoid valves can be used in both low and high voltage refrigeration systems, not just low voltage applications.

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