{"uid":"cap_XpgqopBDL1UOi1dwrwlMP","slug":"hvac-psychrometrics-calculator-40a4a688","name":"HVAC Psychrometrics Calculator","description":"SEC filings and web data for AI agents: read any section of a US public company's 10-K or 10-Q (risk factors, MD&A, …) since 2001, see what changed in it since last year, its latest 8-K events and press releases, and a free index of its filings; turn any web page into clean Markdown; profile a domain's email setup; HVAC engineering calculations (psychrometrics, coil loads, duct sizing) with every step shown. No accounts or API keys: pay per call in USDC with x402. Discovery endpoints are free; paid endpoints use the x402 v2 protocol with USDC on Base. Call a paid endpoint, receive 402 with a PAYMENT-REQUIRED header, sign the payment, and retry with PAYMENT-SIGNATURE. Libraries such as @x402/fetch do this transparently. Which tool: What filings does a company have? Which year's report or which 8-K do I want? → sec_list_filings (free). What are a company's risk factors? What did management say in the MD&A? What was in an earlier year's report? → sec_filing_section ($0.01). What changed in a company's risk factors (or MD&A, business, legal proceedings) since last year? Which new risks were added? → sec_section_changes ($0.04). I need several sections of the same report (e.g. risk factors and MD&A). → sec_filing_sections ($0.015). What are a company's revenue, profit, EPS, cash, debt and free cash flow over the last years or quarters? → sec_financials ($0.005). Are a company's insiders (CEO, CFO, directors) buying or selling its stock? → sec_insider_trades ($0.005). What happened at a company lately: earnings, CEO/CFO changes, acquisitions, cybersecurity incidents? → sec_recent_events ($0.01). Which companies' SEC filings mention a phrase (\"material weakness\", \"tariff\", a product or a person)? → sec_full_text_search ($0.01). Who is this company (from a domain, name or ticker): what it does, HQ, founders, CEO, employees, ticker? → company_profile ($0.01). Is this person, company or crypto wallet on a US sanctions (OFAC) list? → sanctions_screen ($0.005). Where are US interest rates, inflation and unemployment right now? → economic_indicators ($0.003). What does this web page, article, PDF, feed or documentation say? → scrape_markdown ($0.002). Read several pages at once, or find a site's pages (pricing, docs, blog) first? → site_map ($0.002). Is this email address real and safe to send to? → email_verify ($0.002). Who hosts a company's email, is SPF/DMARC set up, which SaaS does it use? → domain_enrich ($0.004). HVAC: what are the dew point, enthalpy, RH and humidity ratio of air (from any two properties, at any elevation)? → hvac_psychrometrics ($0.002). HVAC: what is the cooling or heating coil load (sensible, latent, tons), or the mixed air with outdoor air? → hvac_coil_load ($0.002). HVAC: what size duct for this airflow (equal friction or velocity), or what friction and velocity in this duct? → hvac_duct_size ($0.002). Inputs are forgiving: name a company by ticker, CIK or name; sections as \"Risk Factors\", \"MD&A\" or \"Item 1A\"; 8-K events as codes (5.02) or words (earnings, executive changes); unknown fields are ignored. Invalid input returns a valid example, and failed calls are never charged. Every paid result ends with `next_calls`: the natural follow-up questions as ready-to-send calls with their price. Live reliability (answers, failures and latency per tool) is published at /status.","url":"https://x402-agent-api.onrender.com/api/v1/hvac-psychrometrics?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"units":{"enum":["IP","SI"],"type":"string","default":"IP","description":"\"IP\" (°F, CFM, in, BTU) or \"SI\" (°C, L/s, mm, kW). Default IP. Applies to inputs and results."},"grains":{"type":"number","minimum":0,"description":"Moisture in grains per lb dry air (gr/lb), in either unit system (7,000 gr = 1 lb)."},"dry_bulb":{"type":"number","description":"Dry-bulb temperature, °F (IP) or °C (SI)."},"enthalpy":{"type":"number","description":"Enthalpy: BTU per lb dry air (IP) or kJ/kg dry air (SI)."},"wet_bulb":{"type":"number","description":"Wet-bulb temperature, °F or °C."},"dew_point":{"type":"number","description":"Dew-point temperature, °F or °C."},"elevation":{"type":"number","default":0,"maximum":30000,"minimum":-1500,"description":"Site elevation, ft (IP) or m (SI); sets the atmospheric pressure. Default 0 (sea level)."},"humidity_ratio":{"type":"number","minimum":0,"description":"Humidity ratio: lb water per lb dry air (IP, e.g. 0.0100) or g/kg (SI, e.g. 10.0)."},"relative_humidity":{"type":"number","maximum":100,"minimum":0,"description":"Relative humidity, % (0-100)."}}},"responseSchema":{"type":"json","example":{"notes":[],"state":{"grains":98.46,"density":0.07092,"dry_bulb":95,"enthalpy":38.316,"wet_bulb":75,"dew_point":66.76,"humidity_ratio":0.014065,"vapor_pressure":0.325,"specific_volume":14.2995,"relative_humidity":39.82},"steps":[{"step":"Atmospheric pressure","reference":"ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics, Eq. 3","calculation":"p = 14.696 × (1 − 6.8754×10⁻⁶ × Z)^5.2559 = 14.696 × (1 − 6.8754×10⁻⁶ × 0)^5.2559 = 14.6960 psia"},{"step":"Humidity ratio","reference":"ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics","calculation":"pws(75.00 °F wet bulb) = 0.43007 psia (ASHRAE Ch. 1 Eq. 6)"},{"step":"Humidity ratio","reference":"ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics","calculation":"Ws* = 0.621945 × pws / (p − pws) = 0.018750 lb/lb (saturated at the wet bulb)"}],"units":"IP","pressure":14.696,"elevation":0,"next_calls":[{"why":"What load does a coil carry cooling this air to 55/54 °F at 1000 CFM?","tool":"hvac_coil_load","price":"$0.002","arguments":{"units":"IP","airflow":1000,"leaving":{"dry_bulb":55,"wet_bulb":54},"entering":{"dry_bulb":95,"wet_bulb":75}}}],"references":["ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics"],"inputs_used":{"dry_bulb":95,"wet_bulb":75},"unit_labels":{"area":"ft²","load":"MBH (1,000 BTU/h)","grains":"gr / lb dry air","length":"in","airflow":"CFM","density":"lb / ft³","enthalpy":"BTU / lb dry air","pressure":"psia","velocity":"FPM","elevation":"ft","condensate":"gal / h","temperature":"°F","friction_rate":"in. w.g. / 100 ft","humidity_ratio":"lb water / lb dry air","specific_volume":"ft³ / lb dry air","relative_humidity":"%","velocity_pressure":"in. w.g."}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_MPZYOd_DDsqpQcne-WjI-","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the full psychrometric state of moist air (dry-bulb, wet-bulb, dew point, enthalpy, humidity ratio, density, etc.) from any two known properties, with every ASHRAE-referenced calculation step shown","exampleAgentPrompt":"Calculate the full psychrometric state of air at 95°F dry-bulb and 75°F wet-bulb at sea level in IP units — I need the enthalpy, dew point, humidity ratio, relative humidity, and density, plus every ASHRAE calculation step.","exampleUseCases":[{"title":"Data center cooling air analysis","prompt":"What are the full psychrometric properties of air at 68°F dry-bulb and 50% relative humidity at sea level in IP units? I need enthalpy, humidity ratio, dew point, and specific volume with all the calculation steps shown."},{"title":"High-altitude HVAC design in SI","prompt":"Calculate the psychrometric state of outside air at 30°C dry-bulb and 22°C wet-bulb for a site at 1500 meters elevation — give me all properties in SI units including density and enthalpy."},{"title":"Verify dew point for condensation risk","prompt":"I have air at 78°F dry-bulb with a humidity ratio of 0.0120 lb/lb at sea level in IP units — what is the dew point temperature and relative humidity? Show me the ASHRAE equations used."}],"resultDescription":"Returns the complete psychrometric state of moist air including dry-bulb, wet-bulb, dew-point, relative humidity, enthalpy, humidity ratio, grains per pound, specific volume, vapor pressure, and density — along with atmospheric pressure for the given elevation, step-by-step ASHRAE-referenced calculations, unit labels, and suggested next API calls (e.g. coil load calculation).","failureModes":["Underdetermined system: fewer than two independent psychrometric properties provided — returns error asking for additional input","Overdetermined or contradictory inputs (e.g. wet-bulb higher than dry-bulb) — returns validation error","Elevation out of range (below -1500 ft or above 30000 ft) — schema validation error","Relative humidity out of 0–100 range — schema validation error","Payment not included — returns HTTP 402 with PAYMENT-REQUIRED header requiring USDC payment on Base via x402 protocol"],"whenToPreferThis":"Choose this endpoint when you need accurate ASHRAE-compliant psychrometric calculations with full step-by-step derivations shown, especially for HVAC design, load calculations, or engineering documentation. It supports both IP and SI unit systems and handles elevation-adjusted atmospheric pressure. Use it before calling the coil load or duct sizing endpoints when you need to establish the entering/leaving air state. Prefer this over generic calculators when ASHRAE Handbook references and intermediate calculation steps are required for engineering compliance.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-10T06:46:18.823Z","isFirstParty":false,"canonicalSlug":"hvac-psychrometrics-calculator-40a4a688"}