DENOVA — Fan Selector v2.2

Project Info

Name, location & altitude

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Fan Duty Point

Flow, pressure, density & type

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Calculate & Review

All results resolved instantly

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Chart & Report

→ View Curve → Report

Project Information

Project Name Client project identifier

Reference Drawing or document reference

Engineer Responsible engineer

Location Site or city

Project Altitude (m) Actual installed altitude — overrides density. ISO 2533 P_atm correction.

P_atm (kPa) Calculated from altitude

101.325

Fan Tag / Reference Equipment tag on drawing

Date Calculation date

Fan Configuration

Fan TypeAerodynamic classification

ApplicationSystem use classification

AHU Fan Position Draw-through vs blow-through arrangement

Drive Type

Motor Enclosure

InstallationAffects System Effect Factor — AMCA 201

SEF — AMCA 201 — In-duct installation. Lowest System Effect — ensure ≥3 duct diameters of straight duct at inlet and outlet. SEF not calculated in this tool. Add to design FSP before final fan selection. Ref: AMCA Publication 201-02.

SEF Quantification — AMCA 201

Inlet ConnectionFan inlet duct arrangement — AMCA 201 Fig. 1

Outlet ConnectionFan outlet duct arrangement — AMCA 201 Table 8

SEF Addition (AMCA 201)Add to FSP — based on connection velocity pressure

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Corrected FSP + SEFUse this value for final fan catalogue selection

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Airfoil (AF)

Best efficiency centrifugal fan. Ideal for AHU and duct systems at 300–1200 Pa. Widest stable operating range. Not suitable for contaminated or sticky airstreams.

Fan Motor Assembly

Live Assembly Preview — updates with selection

Duty Point

Volume Flow RateL/s

Fan Static Pressure (FSP)Pa — system resistance at design flow (AMCA 210 / ISO 5801)

Air Temperature°C

Site Altitudem

Safety FactorApplied to flow & pressure

Air Densitykg/m³ — ISO 2533

1.190

Density-Corrected Design Duty

Design Flow w/ SF

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Fan Static Pressure w/ SF

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Density-Corrected FSPFSP × (1.2 / ρ) — use for fan catalogue

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Velocity Pressure Pv½ρv² at ~5 m/s duct velocity

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Fan Total Pressure (FTP)FSP + Pv — AMCA 210

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Atmospheric PressureISO 2533 altitude correction

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Air Mass Flowṁ = Q × ρ (kg/s)

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Fan P-Q Curve & System Characteristic

Hover over chart to inspect values

Operating Point

Run calculation on Fan Duty tab first.

System Characteristic

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Duct System Resistance Builder Darcy-Weisbach · ε=0.09mm galv. sheet metal · ASHRAE HVAC Handbook

CRITICAL PATH — Add the highest-resistance path only. Include supply and return duct if a draw-through AHU fan. Total ΔP should match your FSP input above.

Type	Description	Parameters	Velocity	Pv (Pa)	ΔP (Pa)

No components added — use the buttons above to build your system resistance.

Advanced System Curve Options static lift · multi-branch index circuit — SMACNA / CIBSE Guide B2

STATIC LIFT / PRESSURISATION (ΔP_static)

WHAT IS THIS — Use when the system has a non-zero pressure at zero flow: kitchen exhaust stack buoyancy, building pressurisation, height difference, or fire stairwell pressurisation. System curve: ΔP = ΔP_static + k·Q²

Static Lift ΔP_static (Pa)

Adjusted ΔP at design Q

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Static fraction of total

—

Effective system k

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MULTI-BRANCH INDEX CIRCUIT

INDEX CIRCUIT — The highest-resistance branch. Fan must meet index ΔP. Other branches need balancing dampers to absorb excess pressure.

0 branches

Add branches to calculate index circuit.

System Curve Data Table

% Flow	Flow (L/s)	System ΔP (Pa)	Fan ΔP (Pa)	Power (kW)	Efficiency (%)

Fan Affinity Laws — Speed Change

Speed Change Calculator

N₁ — Original Speed (%)Reference speed (100% = design)

N₂ — New Speed (%)Target speed to calculate

Q₁ (L/s)

P₁ (Pa)

W₁ — Shaft Power (kW)

New Duty at N₂

Q₂ = Q₁ × (N₂/N₁)

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P₂ = P₁ × (N₂/N₁)²

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W₂ = W₁ × (N₂/N₁)³

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Power Ratio (N₂/N₁)³

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Power Saving (%)

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Density Change Calculator

ρ₁ — Original Density (kg/m³)From duty point (auto-filled)

ρ₂ — New Density (kg/m³)Target operating density

Or enter new conditions:

New Altitude (m)

New Temperature (°C)

Density-Corrected Duty

NOTE — Flow is unchanged for density variation. Only pressure and power scale.

P₂ = P₁ × (ρ₂/ρ₁)

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W₂ = W₁ × (ρ₂/ρ₁)

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Density Ratio (ρ₂/ρ₁)

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P-Q CURVE SUPERPOSITION — parametric (indicative)

─ Single fan ─ Combined ─ System curve ● Op. point

Combined Speed & Density Change Q₂=Q₁·(N₂/N₁) · P₂=P₁·(N₂/N₁)²·(ρ₂/ρ₁) · W₂=W₁·(N₂/N₁)³·(ρ₂/ρ₁) — AMCA 201

ORIGINAL CONDITION (auto-filled from Fan Duty)

N₁ Speed (%)

ρ₁ (kg/m³)

Q₁ (L/s)

P₁ (Pa)

W₁ (kW)

NEW CONDITION

N₂ Speed (%)

ρ₂ (kg/m³)

Or compute ρ₂ from:

Alt (m)

Temp (°C)

COMBINED RESULT

Q₂ (L/s)

—

P₂ (Pa)

—

W₂ (kW)

—

Speed ratio N₂/N₁

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Density ratio ρ₂/ρ₁

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Power change

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Parallel & Series Fan Arrangement

Arrangement

Single Fan Flow (L/s)

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Single Fan Pressure (Pa)

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Combined Flow (L/s)

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Combined Pressure (Pa)

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VFD Speed vs Power Table

Speed (%)	Est. RPM	Flow (L/s)	Pressure (Pa)	Power (kW)	Power Saving (%)	Ann. Energy (kWh)

CUBE LAW — Power saving at 80% speed = 49% | at 70% speed = 66% | at 60% speed = 78%. VFD control delivers exceptional part-load savings.

Fan Schedule

Add fans from the Fan Duty tab — compare, export, manage your project schedule

No fans scheduled

Set up a fan on the Fan Duty tab, run a calculation,
then click ＋ Add to Schedule

ESTIMATED DATA All performance values are calculated from generic fan type models — not manufacturer-measured data. Obtain AMCA 210-certified P-Q curves and AMCA 300-certified sound power data from the manufacturer before procurement. SEF and acoustic values are indicative only.

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Design Flow

L/s

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Total SP

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Shaft Power

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Fan Efficiency

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SFP W/[L/s]

Fan Performance Rating AMCA 205 efficiency class · FEI estimate · operating confidence

FAN EFFICIENCY

Efficiency RangeTypical for type

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AMCA 205 ClassFan Energy Grade

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FEI (indicative)AMCA 208 estimate

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Motor IE ClassIEC 60034-30-1

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OPERATING CONFIDENCE

PARAMETRIC MODEL — Efficiency values are indicative (±10–15%). Obtain AMCA 210-certified manufacturer data before final equipment specification.

Power uncertainty

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Acoustic uncertainty

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COMPLIANCE SUMMARY

ASHRAE 90.1 FEG

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NCC 2022 SFP

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AS 1668.2 flow

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Motor Sizing

Shaft Power

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Recommended Motor

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Drive Loss

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Motor Loading

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Motor Input Power

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Motor Efficiency est.

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IE Efficiency ClassIEC 60034-30-1 — minimum IE3 required

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Motor Frame (IEC)

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Service Factor

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Enclosure / IP Rating

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Supply Frequency

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Motor Speed est. (RPM)

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Motor Heat GainIf motor is in airstream — see note below

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Electrical Indicative — verify per AS/NZS 3000:2018 & AS/NZS 3008.1

Supply Voltage

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Phase

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Estimated FLC (A)Full Load Current — IEC 60947-2

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Locked Rotor Current (A)LRC ≈ 6–7× FLC — for switchboard sizing

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Starting Method

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Circuit Breaker / MCCBAS/NZS 3000 Cl. 2.5

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Cable Size est.AS/NZS 3008.1 — verify derating factors

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Recommended Isolator

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Power Factor est.

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Motor Starting Analysis Indicative — verify with motor supplier · AS/NZS 3000 Cl. 2.5

Starting Method All curves drawn on chart · selected method highlighted

Starting Current Peak inrush at t=0

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Inrush Multiple × FLC — switchboard sizing

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Starting kVA Peak apparent power

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Accel. Time To full speed (N² fan load)

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Running Current FLC at rated speed

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Starting current vs time — all methods shown, selected method highlighted · fan load curve (torque ∝ N²)

Specific Fan Power (SFP)

SFPW/(L/s) — NCC 2022 / CIBSE benchmark

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SFP RatingNCC 2022 / CIBSE benchmark

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Annual Energy est.At 70% hrs factor

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Variable Load Energy Profile NCC 2022 Section J · bin method · VFD cube law

OCCUPANCY PROFILE

Building Type

Drive Type

Electricity Tariff $/kWh (AUS avg $0.28)

CO₂ Factor kgCO₂e/kWh (AUS grid avg)

ANNUAL ENERGY BREAKDOWN

Speed	Hours/yr	Power (kW)	Energy (kWh)	Cost ($)	CO₂ (kg)
TOTAL	—	—	—	—	—

VS DOL FIXED SPEED

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kWh/yr (DOL comparison)

VFD SAVING

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kWh/yr & $/yr saved vs DOL

Noise — Octave Band Analysis

Overall Lw (A-weighted)dB(A) re 1pW — AMCA 300 / ASHRAE HoF method

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Blade Pass FrequencyBPF = (RPM/60) × blade count — dominant tonal

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Dominant Octave BandHighest A-weighted band — target for attenuation

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Fan Heat Rise (impeller)ΔT through fan wheel — motor-in-stream adds more

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Octave band Lw — indicative per ASHRAE HoF Ch.49 / AMCA 300. Obtain AMCA-certified data from manufacturer.

Vibration Isolation

Isolation Type

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Static Deflection

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Balance GradeISO 14694:2003 — fan balance quality

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Vibration LimitISO 20816-3 — velocity RMS at bearing housing

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Wheel Diameter est.Indicative — confirm with manufacturer

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Bearing Life & Vibration Isolation ISO 281 · ISO 20816-3 · ASHRAE HoF Ch.48

BEARING LIFE — ISO 281

Estimated Speed

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Bearing Dyn. Load C

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Shaft Load P

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C/P Ratio

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L10 Life (hrs)

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L10 (years)

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Maintenance Interval

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VIBRATION ISOLATION DESIGN

Mount Type

Operating Freq (Hz)

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Isolator fn (Hz)

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Static Deflection δ

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Freq Ratio r = f/fn

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Transmissibility Tr

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Isolation Efficiency

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TRANSMISSIBILITY CURVE

─ Transmissibility vs r=f/fn ● Operating point

Inertia Base Rec.

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Flexible Conn. Req.

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Duct Acoustic Attenuation Path ASHRAE HoF Ch.48 — fan Lw through ductwork to grille

HOW TO USE — Build the duct path from fan outlet to grille. Add components in order: straight sections, elbows, branches, lined sections, end reflection. The resulting Lw at grille feeds directly into Room Acoustic Analysis below.

0 components

No path components added — room acoustics uses raw fan Lw.

Room Acoustic Analysis Lw → Lp · ASHRAE HoF Ch.48 · NC curve evaluation

NOTE — This analysis treats fan Lw as if radiated from the supply diffuser(s). In practice, apply duct insertion loss before this step. Obtain AMCA-certified octave-band data for final acoustic design.

Room Dimensions

Length (m)

Width (m)

Height (m)

Volume / Surface

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Acoustic Properties

Room Type

Noise Standard

Avg absorption ᾱ

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Room constant RS·ᾱ/(1−ᾱ) — Sabine, m²

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RT60Reverberation time — Sabine eq.

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Source / Receiver

Directivity Q

Distance to receiver (m)

Target space

Critical distanceWhere direct = reverberant field

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Band	63 Hz	125 Hz	250 Hz	500 Hz	1 kHz	2 kHz	4 kHz	8 kHz	Total

Lp at receiverA-weighted sound pressure level

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Estimated NC ratingLowest NC curve not exceeded

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Compliance

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Direct field levelQ/(4πr²) component

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Reverberant field level4/R component

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Field type

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Octave band Lw vs Lp at receiver vs NC target — ASHRAE HoF Ch.48

Commissioning Checklist Site engineer reference — ISO 14694 · AS/NZS 3000 · manufacturer data takes precedence

Pre-Start Checks

Run calculation first.

Motor & Starter Settings

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Acceptance Criteria

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Drive Settings

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Checks & Warnings

PRO Need a built-in fan manufacturer database, multi-fan schedule, or branded PDF submittals? — Upgrade to DENOVA Fan Selector Pro

Status: ✓ Acceptable

DENOVA

Fan Selector

LITE v2.1

Project: —

Number: —

Fan Tag: —

By: —

Date: —

✓ Acceptable

1. Fan Selection Summary

Duty Inputs
Fan Type	—
Application	—
Drive Type	—
Motor Enclosure	—
AHU Fan Position	—
Design Flow	—
Total Static Pressure	—
Air Temperature	—
Altitude	—
Air Density	—
Safety Factor	—

Calculated Results
Design Flow w/ SF	—
Design Pressure w/ SF	—
Shaft Power	—
Fan Efficiency	—
Motor Input Power	—
Recommended Motor	—
Motor Loading	—
Estimated FLC	—
SFP	—
SFP Rating	—
ASHRAE 90.1 FPL	—
EU ErP MEI	—
EN 13779 SFP Cat.	—
Region / Frequency	—

2. System Curve

% Flow	Flow (L/s)	Flow (m³/s)	System ΔP (Pa)	Fan ΔP (Pa)	Power (kW)	Efficiency (%)

3. Motor & Electrical

Motor Sizing
Shaft Power	—
Drive Loss	—
Motor Input Power	—
Motor Efficiency est.	—
Recommended Motor (kW)	—
IE Efficiency Class	—
Motor Frame (IEC)	—
Motor Loading	—

Electrical — Ref: AS/NZS 3000:2018
Supply Voltage	—
Phase	—
Estimated FLC	—
Locked Rotor Current	—
Starting Method	—
Circuit Breaker	—
Cable Size est.	—

4. SFP, SEF, Pressure, Noise & Vibration

Energy & Pressure
Fan Static Pressure (FSP)	—
Velocity Pressure Pv	—
Fan Total Pressure (FTP)	—
SFP	—
SFP Rating	—
Annual Energy est.	—
Fan Heat Rise (impeller)	—

SEF — System Effect (AMCA 201)
Inlet Connection	—
Outlet Connection	—
SEF Addition	—
Corrected FSP + SEF	—
Use corrected FSP for final fan catalogue selection

Noise & Vibration
Sound Power Lw (A-weighted)	—
Blade Pass Frequency	—
Dominant Octave Band	—
Test Method Ref	AMCA 300-14 / ASHRAE HoF Ch.49
Isolation Type	—
Static Deflection	—
Balance Grade	—
Vibration Limit	—
Wheel Diameter est.	—

AHU Pressure Drop Breakdown
Filter Bank ΔP	—
Cooling Coil ΔP	—
Duct System ΔP	—
Terminals / Diffusers ΔP	—
Other Components ΔP	—
Total Component FSP	—

Octave Band Sound Power — Lw (dB re 1pW) — ASHRAE HoF Ch.49 / AMCA 300 indicative
Lw (dB)	—	—	—	—	—	—	—	—
Lw(A) (dB)	—	—	—	—	—	—	—	—

5. Checks & Warnings

Coil Duty
Total Cooling Load	—
Sensible Load	—
Latent Load	—
Sensible Heat Ratio	—
Coil ΔT	—
Supply Air Temperature	—
OA Fraction	—

Room & Source
Room Dimensions	—
Room Type	—
Room Constant R	—
RT60	—
Directivity Q / Distance	—

Acoustic Results
Lp at Receiver (A-wtd)	—
Estimated NC Rating	—
Target Space / NC	—
Compliance	—
Critical Distance	—

DENOVA Fan Selector v2.2 | Generated: —

Standards reference list below

ASHRAE HoF Ch.48 — Room acoustics, NC/RC curves, Lw→Lp

ASHRAE HoF Ch.49 — HVAC fan noise prediction methods

AMCA 210-16 — Fan aerodynamic performance testing

AMCA 300-14 — Fan sound power testing (reverberant room)

AMCA 301-14 — Fan sound rating calculation method

AMCA Publication 201-02 — Fans & Systems (SEF, affinity laws)

ISO 5801:2017 — Fan performance testing (metric)

ISO 2533:1975 — Standard atmosphere / air density

ISO 14694:2003 — Fan balance quality & vibration levels

ISO 20816-3 — Machine vibration evaluation

IEC 60034-30-1:2014 — Motor efficiency classes IE1–IE4

AS/NZS 3000:2018 — Wiring Rules

AS/NZS 3008.1 — Cable current ratings

AS 1668.1 — Smoke exhaust systems

AS 1668.2 — Mechanical ventilation

AS/NZS 1269.1 — Occupational noise management

NCC 2022 Section J — Energy efficiency (SFP benchmarks)

ASHRAE 90.1 — Energy standard for buildings

CIBSE TM54 — SFP evaluation methodology

Terms, Disclaimer & Intellectual Property

DISCLAIMER

All outputs are advisory estimates suitable for concept-stage and tender-stage design only. Fan selections, duty points, sound levels, vibration analysis, motor sizing, and cable sizes must be verified by a qualified engineer using manufacturer-certified performance data before procurement, fabrication, or installation. DENOVA Systems makes no warranty as to the accuracy, completeness, or fitness-for-purpose of any output. Use is at the user's discretion and risk.

CALCULATION BASIS

Public-domain engineering equations only — affinity laws (Stepanoff 1948), Euler turbomachinery equations, ISA atmosphere model, AMCA 201 system effect methodology, ISO 5801 fan performance test conventions. Octave-band acoustics use ASHRAE Ch.48 simplified attenuation formulas with ANSI S12.2 NC curves. Magnus formula for psychrometrics. Vibration limits per ISO 14694 + ISO 20816-3. Cable sizing per AS/NZS 3008.1, IEC 60364, NEC 310.16 tables.

STANDARDS REFERENCE

References cited (AMCA, ASHRAE, ISO, IEC, AS/NZS, NCC, CIBSE, ERP, NEMA) are publications by their respective copyright holders. DENOVA Fan Selector cites these by name only as reference publications; it does not reproduce copyrighted text, figures, proprietary tables, or licensed datasets from any cited standard.

DATA HANDLING

No telemetry. No analytics. No external API calls at runtime. Project data does not leave the user's browser. CDN scripts (jsPDF) and Google Fonts are fetched at first load only; both are licensed under permissive open-source terms (MIT / SIL OFL).

TRADEMARKS

DENOVA and the DENOVA wordmark are trademarks of DENOVA Systems. AMCA, ASHRAE, ISO, IEC, NEMA and other organisation names are trademarks of their respective bodies. All other trademarks are acknowledged as the property of their respective owners.

DENOVA·denova.systems·Practical Engineering Software·Confidential where applicable

DENOVA LITE — NOT FOR CONSTRUCTION

1. Fan Type Guide ▾

Type	Typical η	Flow Range	Pressure Range	Best Application	Avoid When
Centrifugal AF	78–85%	Any	300–1500 Pa	AHU, clean duct systems	Contaminated/sticky air
Centrifugal BC	70–80%	Any	100–1200 Pa	General ventilation, AHU	Very high pressure (>1200Pa)
Centrifugal FC	55–65%	High flow	50–750 Pa	Low static, high volume	High pressure duties
Axial Vaneaxial	70–82%	High flow	150–600 Pa	In-duct, car parks	Very low/high flow (stall risk)
Axial Tubeaxial	60–72%	High flow	50–400 Pa	General duct exhaust	High pressure, dirty air
Axial Propeller	45–55%	Very high	0–200 Pa	Roof exhaust, free air	Ducted systems >200 Pa
Plug Fan / EC	75–85%	Any	200–1200 Pa	AHU plenum, data centres	Contaminated air, high temp
Mixed Flow	68–78%	High flow	100–600 Pa	Inline duct, car parks	Very high pressure

2. Fan Laws (Affinity Laws) ▾

The fan affinity laws describe how flow, pressure, and power scale with speed at the same system resistance. They are valid for a given fan operating on the same system curve.

Q₂/Q₁ = N₂/N₁            (flow ∝ speed)
P₂/P₁ = (N₂/N₁)²       (pressure ∝ speed²)
W₂/W₁ = (N₂/N₁)³       (power ∝ speed³)

Density Correction:
P₂/P₁ = ρ₂/ρ₁ (flow unchanged)
W₂/W₁ = ρ₂/ρ₁ (power ∝ density)

VFD CUBE LAW — Reducing fan speed by just 20% (to 80%) cuts power consumption by 49%. Reducing to 60% speed cuts power by 78%. This is why VFDs are standard on variable-flow systems.

LIMITATION — Affinity laws are valid only on the same system curve. For different system resistances, use the full P-Q curve intersection method.

DENSITY — For altitude or temperature changes, flow is unchanged. Only pressure and power scale with density ratio. Fan speed and physical geometry are unchanged.

4. AMCA & Standards Reference ▾

Standard	Title	Application in This Tool
AMCA 210-16	Laboratory Methods of Testing Fans for Aerodynamic Performance Rating	Primary certification for fan P-Q curves. Specify AMCA 210 certified fans.
AMCA 300-14	Reverberant Room Method for Sound Testing of Fans	Basis for fan sound power (Lw) data. Noise estimates in tool are indicative only.
AMCA 301-14	Methods for Calculating Fan Sound Ratings from Laboratory Test Data	Calculation method for manufacturer-published acoustic data.
AMCA Pub 201-02	Fans and Systems — Application Guide	Affinity laws, System Effect Factors (SEF), duct connection guidelines. SEF not calculated in this tool — must be added to system resistance manually.
AMCA 99-16	Standards Handbook — Fan Terminology & Definitions	Fan type definitions, pressure terminology (FSP, FTP, FVP).
ISO 5801:2017	Industrial Fans — Performance Testing (metric equivalent of AMCA 210)	International metric standard for fan P-Q curve testing.
ISO 2533:1975	Standard Atmosphere	Air density calculation from altitude and temperature. Used throughout this tool.
ISO 14694:2003	Industrial Fans — Balance Quality & Vibration Levels	Balance grade G2.5 (precision) / G6.3 (normal). Vibration limit basis for this tool.
ISO 20816-3	Mechanical Vibration — Evaluation of Machine Vibration	Bearing housing vibration velocity limits. Zone A/B/C/D classification.
IEC 60034-30-1:2014	Rotating Electrical Machines — Motor Efficiency Classes	IE1 / IE2 / IE3 / IE4 efficiency classes. IE3 is minimum in most jurisdictions.
AS/NZS 3000:2018	Wiring Rules	Governs cable sizing, circuit protection, isolation. All electrical outputs in this tool are indicative — verify with licensed electrician.
AS/NZS 3008.1	Electrical Installations — Selection of Cables	Cable current rating tables with derating for ambient temperature, grouping and installation method.
AS 1668.1	The Use of Ventilation and Air Conditioning — Smoke Control	Smoke exhaust fan requirements including high-temperature motor ratings (300°C/2hr or 400°C/2hr).
AS 1668.2	The Use of Ventilation and Air Conditioning — Mechanical Ventilation	General mechanical ventilation requirements for buildings in Australia.
AS/NZS 1269.1	Occupational Noise Management — Measurement and Assessment	Noise assessment methodology. Note: fan Lw (sound power) ≠ Lp (sound pressure at receiver).
NCC 2022 Sect. J	National Construction Code — Energy Efficiency	SFP limits for HVAC fan systems. Benchmarks A+ through E used in this tool.
ASHRAE 90.1	Energy Standard for Buildings	US energy benchmark reference. SFP limits comparable to NCC Section J.
CIBSE TM54	Evaluating Operational Energy Performance	SFP methodology and A/B/C/D rating scale used in this tool.

CRITICAL — SYSTEM EFFECT (AMCA 201) — Fan performance curves (AMCA 210) are tested under ideal laboratory conditions. In real installations, non-ideal connections at the fan inlet or outlet create additional pressure losses called System Effect Factors (SEF). Common causes: elbow directly at fan inlet, duct area change immediately at discharge, insufficient straight duct length. SEF can range from 15–100+ Pa depending on installation. Always add SEF to system resistance before selecting the fan. Refer to AMCA Publication 201-02 Table 8 for SEF values by installation type.

FSP vs FTP vs FVP (AMCA 99) — Fan Static Pressure (FSP) = pressure rise available to overcome system resistance. Fan Total Pressure (FTP) = FSP + outlet velocity pressure. Fan Velocity Pressure (FVP) = ½ρv² at fan outlet. This tool uses FSP as the primary duty input, consistent with HVAC duct system design practice. Ensure manufacturer data is also stated as FSP when comparing.

IE3 MOTOR REQUIREMENT — IEC 60034-30-1:2014 defines IE efficiency classes. Most Australian jurisdictions (GEMS Determination) mandate IE3 minimum for motors 0.75–375 kW on continuous duty. Specify IE3 or IE4 on all fan motor schedules. Plug fans with EC motors typically achieve IE4+ equivalent.

Rating	SFP W/(L/s)	Description	Standard Reference
A+	≤ 0.5	Excellent — high efficiency selection	CIBSE TM54 / Beyond NCC
A	≤ 0.8	Good — efficient selection	CIBSE TM54
B	≤ 1.25	Acceptable — meets best practice	NCC 2022 Section J / ASHRAE 90.1
C	≤ 1.8	Below average — review selection	NCC 2022 minimum
D	≤ 2.5	Poor — redesign recommended	Fails NCC 2022
E	> 2.5	Unacceptable — non-compliant	Fails NCC 2022 & ASHRAE 90.1

NCC 2022 — Section J Part J6 sets maximum SFP for HVAC fan systems. Values shown are for supply fans in comfort systems. Different limits apply to exhaust, kitchen and industrial systems. Always verify with the applicable edition of NCC for your jurisdiction.

5. Fan Type Comparison — Current Duty ▾

HOW TO USE — Run a fan calculation first, then this table compares all fan types at the same duty. Useful for selecting the best type for your application.

Fan Type	η BEP	η Range	Shaft (kW)	Motor	SFP	Lw(A)	AMCA	Overload	Stall Q
Run a calculation to populate this comparison

6. VFD Power Quality — AS 61000-3-12 Reference ▾

HARMONIC LIMITS — AS/NZS 61000-3-12:2015

Harmonic Order	Max Current THD (%)	Risk Level
VFD input <15kW	≤16% Ithd	Low
VFD input 15-75kW	≤12% Ithd	Moderate
VFD input >75kW	≤8% Ithd	High — harmonic filter required

Mitigation: Line reactor (5% impedance), passive LC filter, active front end (AFE) drive, or 12/18-pulse transformer for large drives >75kW.

CURRENT SYSTEM — VFD ASSESSMENT

Run a calculation with VFD drive type to see harmonic assessment.

Input Power Factor (fundamental): Typical 6-pulse VFD PF ≈ 0.85-0.95 at full load, degrades at part-load. With AFE: PF ≈ 0.99.

AS 61000-3-12 Scope: Applies to equipment with input current per phase >16A. For <16A see AS 61000-3-2.

7. Heat Recovery Ventilation (HRV/ERV) Calculator ▾

HRV INPUTS

Sensible Effectiveness % (typical 70-85%)

OA Supply Temp (°C)

Exhaust/RA Temp (°C)

Air Flow (L/s)

Operating hours/yr

COP of HVAC plant

HRV RESULTS

Pre-heated/cooled supply T

—

Sensible heat recovered

—

Annual energy saved

—

Annual kWh saved (plant)

—

Annual CO₂ avoided

—

Annual $ saved

—

ABOUT HRV EFFECTIVENESS

Sensible effectiveness = (T_supply_actual − T_OA) / (T_exhaust − T_OA) × 100%

Typical values:
Plate heat exchanger: 65–80%
Rotary wheel: 70–85%
Run-around coil: 45–65%
Heat pipe: 55–70%

AS 1668.6 requires HRV where supply >1000 L/s and ΔT >8°C in climate zones 1–5.

Starting Method	—
Starting Current (peak)	—
Inrush Multiple	—
Starting kVA Demand	—
Acceleration Time est.	—