HVAC rectangular-room air-change flow
User-supplied measurements and assumptions; Room volume × supplied air changes per hour; no prescribed ventilation-rate lookup.
HVAC and indoor environmental systems ↗HVAC and indoor environmental systems calculators
25 calculators. Search or choose one below.
Calculators
HVAC occupant outdoor-air worksheet
User-supplied measurements and assumptions; Outdoor airflow = occupant count × rate/person + area × rate/area; user supplies applicable rates.
HVAC and indoor environmental systems ↗HVAC duct section velocity
User-supplied measurements and assumptions; Velocity = volume flow / section area; rectangular hydraulic diameter = 2wh/(w+h).
HVAC and indoor environmental systems ↗HVAC constant-friction round duct size
User-supplied measurements and assumptions; Solve Darcy-Weisbach pressure gradient fρv²/(2D), v=4Q/(πD²), assuming constant supplied f.
HVAC and indoor environmental systems ↗HVAC common-velocity fitting loss
User-supplied measurements and assumptions; Sum K coefficients at one common reference velocity; Δp=ΣKρv²/2.
HVAC and indoor environmental systems ↗HVAC fan-curve pressure interpolation
User-supplied measurements and assumptions; Piecewise-linear interpolation between increasing measured airflow points; extrapolation rejected.
HVAC and indoor environmental systems ↗HVAC fan affinity adjustment
User-supplied measurements and assumptions; Same fan and density: flow ∝ speed, pressure ∝ speed², power ∝ speed³.
HVAC and indoor environmental systems ↗HVAC air balancing deviation
User-supplied measurements and assumptions; Compare each measured airflow with its specified target; report signed percentage deviations.
HVAC and indoor environmental systems ↗HVAC diffuser throw observation
User-supplied measurements and assumptions; Interpolate distance at a user-supplied terminal air speed from a monotonically falling measured profile.
HVAC and indoor environmental systems ↗HVAC grille free-area velocity
User-supplied measurements and assumptions; Free area = nominal area × supplied fraction; velocity = airflow/free area.
HVAC and indoor environmental systems ↗HVAC linear filter pressure trend
User-supplied measurements and assumptions; Least-squares linear pressure trend; project threshold crossing, with no filter-life guarantee.
HVAC and indoor environmental systems ↗HVAC supplied cooling-duty split
User-supplied measurements and assumptions; Latent duty = total − sensible; sensible heat ratio = sensible/total.
HVAC and indoor environmental systems ↗HVAC latent-duty condensate mass
User-supplied measurements and assumptions; Latent duty / supplied vaporization enthalpy gives mass rate; no psychrometric state inference.
HVAC and indoor environmental systems ↗HVAC heat-recovery effectiveness
User-supplied measurements and assumptions; Supply temperature rise divided by maximum inlet temperature difference; equal heat-capacity rates assumed.
HVAC and indoor environmental systems ↗HVAC economizer mixing fraction
User-supplied measurements and assumptions; Dry sensible mixing at equal specific heat; outdoor fraction=(return−mixed)/(return−outside).
HVAC and indoor environmental systems ↗HVAC conductive room heat balance
User-supplied measurements and assumptions; Σ(U×area)×temperature difference minus entered gains; excludes ventilation and thermal storage.
HVAC and indoor environmental systems ↗HVAC linear setback recovery projection
User-supplied measurements and assumptions; Least-squares trend projection from observed recovery temperatures, not a thermal plant simulation.
HVAC and indoor environmental systems ↗HVAC operative-temperature input explorer
Thermal-input explorer through operative temperature; not PMV/PPD, comfort certification or heat-stress assessment.
HVAC and indoor environmental systems ↗HVAC duct leakage test normalization
User-supplied measurements and assumptions; Normalize supplied leak flow by power law Qreference=Qtest(Preference/Ptest)^n.
HVAC and indoor environmental systems ↗HVAC refrigerant tube volume inventory
User-supplied measurements and assumptions; Geometric pipe volume × supplied uniform fluid density; not refrigerant charging instructions.
HVAC and indoor environmental systems ↗HVAC filter bank face area
User-supplied measurements and assumptions; Sum parallel filter face areas; divide airflow by that total area.
HVAC and indoor environmental systems ↗HVAC rectangular service clearance margins
User-supplied measurements and assumptions; Available clearance minus user-entered manufacturer requirement in each dimension; no regulatory clearance lookup.
HVAC and indoor environmental systems ↗HVAC noise level combination
User-supplied measurements and assumptions; Logarithmic energy sum of mutually uncorrelated sound levels with the same weighting and observation point.
HVAC and indoor environmental systems ↗HVAC ventilation schedule energy
User-supplied measurements and assumptions; Integrate piecewise-constant power over supplied schedule durations.
HVAC and indoor environmental systems ↗HVAC commissioning evidence count
User-supplied measurements and assumptions; Accepted/required record count; accepted entries must not exceed requirements.
HVAC and indoor environmental systems ↗No matches. Try a shorter search or another category.