Hvac Coil Load

{
  "airflow": 10000,
  "condensate": 13.69,
  "elevation": 0,
  "entering": {
    "density": 0.07301,
    "dew_point": 60.32,
    "dry_bulb": 80,
    "enthalpy": 31.447,
    "grains": 78.18,
    "humidity_ratio": 0.011169,
    "relative_humidity": 51.1,
    "specific_volume": 13.8494,
    "vapor_pressure": 0.25926,
    "wet_bulb": 67
  },
  "leaving": {
    "density": 0.07667,
    "dew_point": 53.29,
    "dry_bulb": 55,
    "enthalpy": 22.569,
    "grains": 60.42,
    "humidity_ratio": 0.008631,
    "relative_humidity": 93.95,
    "specific_volume": 13.1549,
    "vapor_pressure": 0.20116,
    "wet_bulb": 54
  },
  "loads": {
    "latent": 122.833,
    "sensible": 270,
    "sensible_heat_ratio": 0.687,
    "tons": 32.736,
    "total": 392.833,
    "total_from_enthalpy": 399.538
  },
  "mixing": null,
  "mode": "cooling",
  "next_calls": [
    {
      "arguments": {
        "airflow": 10000,
        "friction_rate": 0.08,
        "units": "IP"
      },
      "price": "$0.002",
      "tool": "hvac_duct_size",
      "why": "What duct size carries 10000 CFM at 0.08 in. w.g. / 100 ft?"
    }
  ],
  "notes": [],
  "pressure": 14.696,
  "references": [
    "ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics",
    "Standard-air load equations: Qs = 1.08·CFM·ΔT, Ql = 4840·CFM·ΔW, Qt = 4.5·CFM·Δh"
  ],
  "solved_for": "loads",
  "steps": [
    {
      "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",
      "reference": "ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics, Eq. 3",
      "step": "Atmospheric pressure"
    },
    {
      "calculation": "pws(67.00 °F wet bulb) = 0.32772 psia (ASHRAE Ch. 1 Eq. 6)",
      "reference": "ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics",
      "step": "Entering air state"
    },
    {
      "calculation": "Ws* = 0.621945 × pws / (p − pws) = 0.014185 lb/lb (saturated at the wet bulb)",
      "reference": "ASHRAE Handbook—Fundamentals (2021), Ch. 1 Psychrometrics",
      "step": "Entering air state"
    }
  ],
  "unit_labels": {
    "airflow": "CFM",
    "area": "ft²",
    "condensate": "gal / h",
    "density": "lb / ft³",
    "elevation": "ft",
    "enthalpy": "BTU / lb dry air",
    "friction_rate": "in. w.g. / 100 ft",
    "grains": "gr / lb dry air",
    "humidity_ratio": "lb water / lb dry air",
    "length": "in",
    "load": "MBH (1,000 BTU/h)",
    "pressure": "psia",
    "relative_humidity": "%",
    "specific_volume": "ft³ / lb dry air",
    "temperature": "°F",
    "velocity": "FPM",
    "velocity_pressure": "in. w.g."
  },
  "units": "IP"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://x402-agent-api.onrender.com/api/v1/hvac-coil-load' \
  -H 'content-type: application/json' \
  --data-raw '{"airflow":10000,"entering":{"dry_bulb":80,"wet_bulb":67},"leaving":{"dry_bulb":55,"wet_bulb":54}}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://x402-agent-api.onrender.com/api/v1/hvac-coil-load' \
  -H 'content-type: application/json' \
  --data-raw '{"airflow":10000,"entering":{"dry_bulb":80,"wet_bulb":67},"leaving":{"dry_bulb":55,"wet_bulb":54}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.002 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.002" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.002 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fx402-agent-api.onrender.com%2Fapi%2Fv1%2Fhvac-coil-load&method=POST
const res = await pay("https://x402-agent-api.onrender.com/api/v1/hvac-coil-load", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "airflow": 10000,
    "entering": {
      "dry_bulb": 80,
      "wet_bulb": 67
    },
    "leaving": {
      "dry_bulb": 55,
      "wet_bulb": 54
    }
  }),
});
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.002 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.002"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://x402-agent-api.onrender.com/api/v1/hvac-coil-load",
        json={
            "airflow": 10000,
            "entering": {
                "dry_bulb": 80,
                "wet_bulb": 67,
            },
            "leaving": {
                "dry_bulb": 55,
                "wet_bulb": 54,
            },
        },
    )
    print(res.status_code, res.text)