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MRCOOL DIY 5th Gen
Which size do you need?
Room size is the main factor. Measure each room you want to heat and cool, then match it to a BTU size below.
One indoor unit, one outdoor unit
| Size | Room size | Voltage | Lines | Systems from |
|---|---|---|---|---|
| 9K BTU | 150–350 sq ft | 115V | Select · EasyPro · 5th Gen | $1,249 |
| 12K BTU | 351–500 sq ft | 115V | Select · EasyPro · 5th Gen | $1,399 |
| 18K BTU | 501–750 sq ft | 230V | Select · EasyPro · 5th Gen | $1,690 |
| 24K BTU | 751–1,000 sq ft | 230V | Select · EasyPro · 5th Gen | $1,899 |
| 36K BTU | 1,001–1,500 sq ft | 230V | 5th Gen only | $3,769 |
One outdoor unit, one indoor unit per room
| Outdoor unit | Rooms | Total area | Outdoor unit only | Lowest full system | Systems from |
|---|---|---|---|---|---|
| 18K BTU | 2–3 | up to 750 sq ft | $1,555 | 9K + 9K | $3,073 |
| 27K BTU | 2–4 | 751–1,125 sq ft | $2,100 | 9K + 18K | $4,029 |
| 36K BTU | 2–5 | 1,126–1,500 sq ft | $2,543 | 12K + 24K | $4,695 |
| 48K BTU | 2–6 | 1,501–2,000 sq ft | $3,228 | 12K + 36K | $5,696 |
| 55K BTU | 2–6 | 2,001–2,300 sq ft | $3,809 | 18K + 36K | $6,531 |
Systems from = outdoor unit + the 2 lowest-priced air handlers that fill its BTU + a 16 ft line set for each. 55K uses 54K, the closest air handler sizes allow.
How BTU limits work
Indoor units share the outdoor unit's capacity. Say your outdoor unit handles 18,000 BTU and you have two 12,000 BTU air handlers: if both run at full power together, they split the 18,000 BTU between them.
If you usually run one room at a time, a smaller outdoor unit can be enough. If you run every room together, pick an outdoor unit that covers the total.
Still not sure?
Let the finder do the math
Pick how many rooms and the total square footage. The finder names the system and the price.