1. Confirm that 18,000 really is Cooling Capacity
Retail pages often show several numbers together. Copy the actual Cooling Capacity / BTU/h from the model specification or label—not electrical input power and not just the marketing class name.
2. Copy Input Power and compressor type
Two units rated at 18,000 BTU can differ in Input Power, inverter operating range and energy-label values. AC Fit Check therefore asks for the unit’s own specifications and does not treat every “18k” AC as the same product.
3. Compare the model with this room
Enter room dimensions, sun, insulation, windows, city and occupancy. The tool builds an approximate load range, places this specific model inside or outside that range and returns PASS, BORDERLINE or FAIL.
Three rooms, the same 18,000 BTU model: why does the result change?
These are reproducible examples, not purchase recommendations. The ranges come from the published AC Fit Check method and each row’s inputs; open any case to change an assumption.
| Case | Key inputs | Approx. load range | 18,000 BTU verdict |
|---|---|---|---|
| Medium room in Jeddah | 4 × 5 × 2.8 m, two people, standard conditions | 15,574–19,034 BTU/h | Open case: initially inside the range |
| Top-floor room in Riyadh | 4 × 4.5 × 3 m, strong sun, poor insulation, many windows, top floor | 21,728–26,556 BTU/h | Open case: undersized for the load |
| Small mild room in Taif | 3.5 × 4 × 2.8 m, low sun, good insulation, few windows | 8,704–10,638 BTU/h | Open case: clearly oversized |
Quick decision checklist before you pay
- Match the model number between the retailer page and the unit label.
- Confirm that 18,000 is Cooling Capacity in BTU/h, not only a marketing name.
- Record Input Power and annual energy use exactly as the official label shows them.
- Run your real room scenario and save the result URL.
- For BORDERLINE results or unusual rooms, get an HVAC load calculation instead of simply jumping to a larger size.
When should you stop using this checker?
Large spaces, extensive glazing, very high ceilings, kitchens, open plans or sensitive projects need a professional HVAC load calculation.