curl --request POST \
  --url https://api.iotools.cloud/v1/tool/hvac-btu-load-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "length": "15",
  "width": "12",
  "ceilingHeight": "8",
  "climateZone": "moderate",
  "insulationQuality": "average",
  "windowCount": "2",
  "sunExposure": "moderate",
  "occupants": "2"
}
'

{
  "tool": "hvac-btu-load-calculator",
  "tool_version": "1.0.2",
  "outputs": {
    "floorArea": "180 sq ft",
    "btuRequired": "6,500 BTU/hr",
    "acTonnage": "0.54 tons (nearest standard: 0.75 ton)",
    "recommendedUnitSize": "8,000 BTU/hr window/portable unit, or a 0.75-ton central/mini-split system",
    "breakdown": [
      {
        "factor": "Floor area",
        "detail": "15 ft × 12 ft",
        "contribution": "180 sq ft"
      },
      {
        "factor": "Base cooling rate",
        "detail": "25 BTU/sq ft (moderate climate)",
        "contribution": "4,500 BTU/hr"
      },
      {
        "factor": "Ceiling height adjustment",
        "detail": "8.0 ft ceiling",
        "contribution": "×1.00"
      },
      {
        "factor": "Insulation adjustment",
        "detail": "Average",
        "contribution": "×1.00"
      },
      {
        "factor": "Window heat gain",
        "detail": "2 window(s), moderate sun, 1,000 BTU/window",
        "contribution": "+2,000 BTU/hr"
      },
      {
        "factor": "Occupant load",
        "detail": "2 occupant(s), +600 BTU per person beyond 2",
        "contribution": "+0 BTU/hr"
      },
      {
        "factor": "Total cooling load",
        "detail": "",
        "contribution": "6,500 BTU/hr"
      }
    ],
    "notes": "This is a rule-of-thumb estimate for a single room or zone, not a substitute for a professional Manual J load calculation — especially for whole-house or multi-room HVAC design. Oversizing an AC unit causes short-cycling and poor humidity control; undersizing leaves it unable to keep up on the hottest days."
  },
  "credits_used": 5,
  "credits_remaining": null
}