HVAC Sensible/Latent Load Calculator implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t4-084

Effect

Computation or source lookup only

Input and validation requirements

The calculator has an unavoidable undefined-result trap when total load is zero: SHR becomes 0/0 or a nonzero value divided by zero. The specification also leaves the CFM-versus-mass-flow branch selection, humidity-ratio units, and load sign convention insufficiently defined, allowing materially different outputs or sign reversals.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "system": "metric",
    "mass_flow_kg_per_s": 0.5,
    "entering_temperature_C": 30,
    "leaving_temperature_C": 20,
    "entering_humidity_ratio_kg_per_kg_dry_air": 0.018,
    "leaving_humidity_ratio_kg_per_kg_dry_air": 0.01,
    "hfg_kJ_per_kg": 2500
  },
  "expected_outputs": {
    "Qs_kW": 5.03,
    "Ql_kW": 10,
    "Qt_kW": 15.03,
    "SHR": 0.33466467
  },
  "working": "ΔT=30−20=10 K. ΔW=0.018−0.010=0.008 kg/kg. Qs=1.006×0.5×10=5.03 kW. Ql=0.5×2500×0.008=10.00 kW. Qt=5.03+10.00=15.03 kW. SHR=5.03/15.03=0.33466467."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche4/tranche4-results.json