MRCOOL DIY Mini Split Sizing Guide

Which air handler is best for your room size?

The size of your room is the main factor in choosing the right unit. MRCOOL DIY 4th Gen comes in various sizes, each designed to cool and heat specific square footage ranges.

Here's a quick reference for choosing the right BTU based on your room size:

  • 9,000 BTU covers up to 375 square feet.
  • 12,000 BTU covers up to 550 square feet.
  • 18,000 BTU covers up to 800 square feet.
  • 24,000 BTU covers up to 1,050 square feet.
  • 36,000 BTU covers up to 1,550 square feet.

How BTU Limits Work in Your Mini-Split System

You can opt for high BTU air handlers for strong heating and cooling. But, if you plan to run multiple air handlers at the same time, consider the main unit's (condenser) maximum power.

Here’s the deal: Suppose your condenser can handle 18,000 BTU, and you have two indoor air handlers, each at 12,000 BTU. If both run simultaneously, they’ll automatically adjust to 9,000 BTU each to match the condenser's limit. This ensures the system runs safely.

If you usually run one air handler at a time, a lower BTU condenser might be sufficient. But if you plan to use all air handlers together, a higher BTU condenser is the way to go. This lets you enjoy the full power of each air handler without overloading the system.

By considering these factors, you can ensure your MRCOOL DIY 4th Gen unit is perfectly sized for your needs, keeping you comfortable year-round.

For personalized assistance or further clarification, please feel free to contact our customer support via chat or call. Our team is ready to help you make the best choice for your cooling needs.

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What countries do you ship to?

We currently ship to the United States, Canada, Australia and the UK. To enquire about shipping to a different destination, please contact us.

How long will it take to receive my order?

Standard shipping normally takes 3-5 days. Next day shipping is available on all domestic orders (for an additional charge). International shipping times depend on the products and destination (estimated at checkout).

Returns and Refunds

How do I return a product?

Items must be returned within 30 days after receiving your order. Items must be returned in the same condition in which they were received, be unworn/unused, have any tags still attached, and include all the original packaging.

How long will it take to receive my refund?

Refunds are processed within 7 days from when we receive the item(s).