Exin Exam CDCS Topic 2 Question 17 Discussion

Actual exam question for Exin's CDCS exam

Question #: 17
Topic #: 2

[All CDCS Questions]

A computer room with a raised floor has been designed with racks in a hot/cold aisle setup.

What should you recommend for the placement of down-flow air conditioners?

AAir conditioners perpendicular to (at the end of the row of) the Cold-Aisle

BAir conditioners perpendicular to (at the end of the row of) the Hot-Aisle

CAir conditioners should always be placed at both sides of each row of racks

DAir conditioner placement has no influence on cooling effectiveness and efficiency. Hence, they can be placed at any convenient location.

Show Suggested Answer

Suggested Answer: A

In a hot/cold aisle configuration, placing down-flow air conditioners perpendicular to the cold aisle ensures that cool air is directed efficiently into the cold aisles where server intakes are located. This layout allows for optimal cooling performance by aligning the airflow directly with the equipment intakes, minimizing hot spots and enhancing cooling efficiency.

Detailed Explanation:

With a raised floor design, cold air from the air conditioners is supplied into the cold aisle, where server intakes are located. Positioning the air conditioning units perpendicular to the cold aisles ensures that cool air is delivered directly into these aisles, preventing air mixing and optimizing cooling. This setup takes full advantage of the airflow management strategy inherent to the hot/cold aisle configuration.

EPI Data Center Specialist References:

EPI guidelines on cooling emphasize that down-flow air conditioners should be positioned to maximize the effectiveness of cold aisle delivery, which improves cooling efficiency and helps maintain consistent temperatures across server racks.

by Louis at Jul 06, 2025, 05:38 AM

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Charlene

40 minutes ago

I vaguely recall something about needing air conditioners on both sides of the racks, but I can't remember if that was for all setups or just specific ones.

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Chery

6 days ago

I think we practiced a question that mentioned placing air conditioners at the end of the cold aisle to help with cooling efficiency. That feels right.

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Terrilyn

11 days ago

I remember discussing how air conditioners should be placed to optimize airflow, but I'm not sure if it's better to have them at the end of the cold aisle or hot aisle.

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Mendy

17 days ago

I'm a little confused by this question. Isn't the air conditioner placement kind of irrelevant as long as the overall cooling capacity is sufficient? I'm not sure if there's a clear "best" answer here, but I'll give it my best shot.

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Ciara

22 days ago

Okay, I've got this. The key is to place the air conditioners in a way that maximizes the airflow and temperature differential between the hot and cold aisles. Based on that, I believe option B, placing the air conditioners perpendicular to the hot aisle, is the correct answer.

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Raina

28 days ago

Hmm, I'm a bit unsure about this one. The hot/cold aisle setup is something I've learned about, but I'm not entirely confident in my ability to apply that knowledge to recommend the best air conditioner placement. I'll need to think this through carefully.

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Aliza

1 month ago

This seems like a straightforward question about the optimal placement of air conditioners in a hot/cold aisle data center setup. I think I have a good understanding of the principles involved, so I'll carefully consider each option.

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Pamella

3 months ago

I think having them at the end of the Cold-Aisle helps in directing the cool air where it's needed most.

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Selma

3 months ago

Haha, D is clearly the best answer. Why waste time and money on proper placement when you can just put them wherever it's convenient? That's the true IT way!

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Hana

1 month ago

B) Air conditioners perpendicular to (at the end of the row of) the Hot-Aisle

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Alana

2 months ago

A) Air conditioners perpendicular to (at the end of the row of) the Cold-Aisle

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Valentin

3 months ago

But wouldn't that disrupt the airflow and cause inefficient cooling?

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Tatum

3 months ago

I believe the air conditioners should be perpendicular to the Hot-Aisle instead.

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Dorcas

3 months ago

I think C is the way to go. Covering both sides of each row ensures even air distribution and redundancy in case one unit fails.

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Ashton

1 month ago

C) Air conditioners should always be placed at both sides of each row of racks

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Leigha

2 months ago

B) Air conditioners perpendicular to (at the end of the row of) the Hot-Aisle

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Bulah

2 months ago

A) Air conditioners perpendicular to (at the end of the row of) the Cold-Aisle

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Pamella

4 months ago

I agree with Valentin, placing them at the end of the Cold-Aisle makes sense for efficient cooling.

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Valentin

4 months ago

I think the air conditioners should be perpendicular to the Cold-Aisle.

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Jenelle

4 months ago

Definitely B. Placing the air conditioners at the end of the hot aisle ensures that the cold air is directed straight into the racks, maximizing cooling efficiency.

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Alline

3 months ago

It makes sense to have the air conditioners perpendicular to the hot aisle for optimal cooling.

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Wynell

3 months ago

I think option B is the most efficient choice for cooling the racks.

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Evangelina

4 months ago

I agree, placing the air conditioners at the end of the hot aisle is the best option.

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