{"uid":"cap_H1jEXjLcQM5lVL5kk3Jdb","slug":"home-energy-calculators-hvac-sizing-room-ac-btu-25b071e0","name":"Home Energy Calculators – HVAC Sizing (Room AC BTU)","description":"Room air-conditioner BTU from floor area (ENERGY STAR chart), tons, and an under- or over-sizing check against a load.","url":"https://home-energy-calc.x402tookit.com/hvac-sizing?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":[],"properties":{"kind":{"type":"string","description":"cooling (default) or heating, for the check window"},"loadBtuH":{"type":"number","description":"A calculated load in BTU/h (see /heat-loss), 1000 to 600000, to check equipment against"},"roomSqFt":{"type":"number","description":"Room floor area in square feet, 100 to 400 (the range the ENERGY STAR chart covers; 8-foot ceilings)"},"equipmentBtuH":{"type":"number","description":"Equipment capacity in BTU/h (with loadBtuH)"},"equipmentTons":{"type":"number","description":"Or equipment capacity in tons of cooling (1 ton = 12,000 BTU/h)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"asOf":{"type":["null","string"]},"source":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"roomSqFt":{"type":["null","number"]},"disclaimer":{"type":["null","string"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"roomAcBtuH":{"type":["null","number"]},"roomAcTons":{"type":["null","number"]},"roomAcWatts":{"type":["null","number"]},"chartRowSqFt":{"type":["array","null"],"items":{"type":"number"}}}}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_eGI90y9YoUqGFobUMjmSc","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the recommended room air-conditioner BTU/h and tons from floor area using the ENERGY STAR chart, and optionally checks whether a given piece of equipment is correctly sized for a calculated load.","exampleAgentPrompt":"What size room air conditioner do I need for a 250 square foot bedroom, and is a 10,000 BTU window unit the right fit if my calculated cooling load is 9,500 BTU/h?","exampleUseCases":[{"title":"Window AC sizing for a small bedroom","prompt":"My guest bedroom is 180 square feet — what BTU rating should I look for when shopping for a window air conditioner?"},{"title":"Checking whether existing AC is oversized","prompt":"I have a 12,000 BTU window unit in my 150 square foot home office. My heat-loss tool says the cooling load is 7,200 BTU/h — is my AC oversized, undersized, or just right?"},{"title":"Converting equipment tons to BTU for a room","prompt":"I'm looking at a 1.5 ton portable AC for a 300 square foot living room — can you tell me how many BTUs that is and whether it's the right size according to ENERGY STAR guidelines?"}],"resultDescription":"Returns the ENERGY STAR-recommended room AC capacity in BTU/h, tons, and approximate watts for the given floor area, along with the chart row data used. If equipment capacity and a load are provided, also returns a sizing verdict (e.g. correctly sized, oversized, undersized), a list of reasons, a human-readable summary, and any factors not checked.","failureModes":["roomSqFt outside 100–400 ft² range returns a validation error (ENERGY STAR chart only covers that range)","loadBtuH outside 1,000–600,000 BTU/h range rejected","Missing required roomSqFt when sizing check is requested","Invalid 'kind' enum value (must be 'cooling' or 'heating')","Providing equipmentTons and equipmentBtuH together may cause ambiguity or conflict","Network or payment failure returns HTTP 402 or 5xx"],"whenToPreferThis":"Use this endpoint when you need a quick, standards-based room AC sizing estimate grounded in the ENERGY STAR BTU-per-square-foot chart, especially for rooms between 100 and 400 sq ft with standard 8-foot ceilings. It is the right choice when you also want to validate whether existing or planned equipment is correctly sized against a calculated load. Prefer the sibling /heat-loss endpoint first to get a calculated load, then pass that result here for a complete sizing check. Not suitable for whole-house or commercial HVAC sizing, or for rooms outside the 100–400 sq ft range.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T13:15:01.321Z","isFirstParty":false,"canonicalSlug":"home-energy-calculators-hvac-sizing-room-ac-btu-25b071e0"}