Tools

TOOL :: SIGNAL SCALING LIVE

Signal Scaling Calculator

mA / V signal ↔ engineering units, with % of span and a 2-point → slope/offset tab ready to paste into Niagara's ProxyExt.

Analog I/O4-20 mA0-10 VSlope / Offset

TOOL :: THERMISTOR LIVE

Thermistor / RTD Calculator

Temperature ↔ resistance for the common HVAC sensors — 10K Type II / III, Johnson 8.7K, Schneider Type 5, 20K, 3K, 1K Balco, Pt100, Pt1000 — looked up both ways, or identify an unknown sensor from measured readings.

SensorsNTC / RTDT ↔ RID Unknown

TOOL :: MODBUS REGISTERS LIVE

Modbus Register Viewer

A 16-bit register laid out as a clickable bit grid, two-way bound to decimal / hex, with dec / hex / binary readouts.

Modbus16-bitDec / Hex / Bin

TOOL :: MODBUS FC LIVE

Modbus Function Codes & CRC

Function codes and exception codes looked up by name or number, plus an RTU CRC-16 calculator that builds or checks a frame's checksum.

ModbusFunction CodesExceptionsCRC-16

TOOL :: BACNET/IP HEX LIVE

BACnet/IP Hex Converter

The hex address strings EBO shows for BACnet/IP devices ↔ dotted-decimal IP and UDP port, both directions.

BACnet/IPUDP 47808Hex ↔ Dec

TOOL :: BACNET OBJECTS LIVE

BACnet Object Reference

Object types, property identifiers, and the engineering-units enumeration, filterable by name or number — decode object type 1 and property 85 without opening the standard.

BACnetObject TypesProperty IDsEng. Units

TOOL :: BACNET VENDOR IDS LIVE

BACnet Vendor ID Lookup

The full ASHRAE-assigned vendor ID registry as one searchable table — decode the Vendor_Identifier a device reports in its I-Am, or filter 1,600+ manufacturers by name.

BACnetVendor_IdentifierProperty 120Registry

TOOL :: BACNET UNITS LIVE

BACnet Engineering Units Decoder

The full BACnet Units enumeration (property 117) as one filterable table — paste the number a point reports for its units and get the name, or filter all 255 standard values by number, name, or symbol.

BACnetProperty 117Units EnumDecode

TOOL :: BACNET ERRORS LIVE

BACnet Error Code Decoder

Decode the class + code a device returns when it refuses a request, plus reject and abort reasons — what unknown-property, write-access-denied, or an APDU-too-long abort actually means, all searchable.

BACnetError / Reject / AbortClass + CodeDecode

TOOL :: BACNET PRIORITY LIVE

BACnet Priority Array

Set a value or NULL in any of the 16 command slots and watch Present_Value resolve to the lowest non-null slot — the priority stack, Relinquish_Default, and why writing NULL releases an override.

BACnetPriority_ArrayPresent_ValueOverride

TOOL :: PSYCH CHART LIVE

Psychrometric Chart

Walk an AHU through its processes — mix outdoor + return air, then cool, heat, and humidify — on an interactive ASHRAE psychrometric chart that follows the header's US / Metric toggle. Drag OA and RA, or type leaving conditions; coil capacities appear when you set the airflow.

HVACPsychrometricsASHRAEUS / Metric

TOOL :: ECONOMIZER RATIO LIVE

Economizer Ratio Helper

Required %OA to mix outdoor and return air down to a mixed-air dry-bulb setpoint, with a feasibility verdict and an OA-vs-RA enthalpy-changeover sanity check for high-end economizer logic.

HVAC% Outdoor AirMix SetpointEnthalpy Check

TOOL :: MIXED AIR LIVE

Mixed Air Temperature Calculator

Blend three air streams by mass flow (CFMs at the panel) or mass fraction (percentages off a schematic) and read out the full mixed-air state — dry-bulb, humidity, enthalpy, dew point.

HVAC3-Stream MixCFM or %Mixed-Air State

TOOL :: COIL SIZING LIVE

Coil-Sizing Calculator

Total, sensible, and latent capacity for a cooling or heating coil from its entering and leaving air — or run it backwards to solve the leaving-air state from a known load.

HVACCool / HeatSensible / LatentForward & Reverse

TOOL :: COIL FREEZE RISK LIVE

Coil Freeze Risk Checker

Freezestat-season triage: place the mixed air, set it against what is in the tubes — water, glycol, or steam condensate — and get a margin plus a protection verdict.

HVACMAT MarginGlycol / SteamVerdicts

TOOL :: DEW POINT LIVE

Dew Point Calculator

Dry-bulb + RH or wet-bulb to dew point at a glance — wet-bulb, grains, and enthalpy alongside — plus a coil check that flags whether supply air is dropping below the return dew point.

HVACDew PointCoil CheckUS / Metric

TOOL :: REFRIG P-T LIVE

Refrigerant P-T & Superheat Calculator

Saturation pressure ↔ temperature for R-410A, R-22, R-134a, R-407C, R-404A and R-454B — bubble and dew both, so blend glide is in plain sight — plus a superheat / subcooling check off a measured line temperature.

HVAC6 RefrigerantsBubble / DewSuperheat / Subcool

TOOL :: POWER & ENERGY LIVE

Power & Energy Converter

Convert any power or energy unit to all the others — W, kW, BTU/hr, MBH, tons, hp, boiler hp, joules, kWh, therms, MMBtu — bridge power and energy through time, and check a boiler input against its burner turndown.

HVACBTU / kW / hpPower × TimeBoiler Turndown

TOOL :: AIRFLOW LIVE

Airflow & Velocity Pressure

The field airflow square-root, both halves — a VAV box's CFM = K × √VP solved forward or back-solved for K against a hood reading, and pitot velocity V = 4005 × √VP with duct area to CFM.

AirflowK-FactorV = 4005·√VPDuct CFM

TOOL :: AIRSIDE LOAD LIVE

Airside Load Calculator

The airside workhorse trio solved in any direction — sensible q = 1.08 × CFM × ΔT, latent 0.68 × CFM × Δgrains, total 4.5 × CFM × Δh with tons — following the US / Metric toggle.

Airflow1.08 / 0.68 / 4.5Sensible / Latent / TotalUS / Metric

TOOL :: DUCT TRAVERSE LIVE

Duct Traverse Calculator

Average a full pitot traverse the way the math demands — root each reading, then average, V̄ = 4005 × mean(√VP) — with duct area to CFM, plus diffuser Ak-factor flow solved forward or back against a hood.

Airflowmean(√VP)Pitot / TABAk Factor

TOOL :: AIRFLOW CHECK LIVE

Equipment Airflow Check

Judge a measured airflow against equipment limits — CFM per active ton of DX cooling with staging-aware icing / carryover verdicts, and the gas-furnace rise window turned into an allowable CFM band.

AirflowCFM / Active TonRise WindowVerdicts

TOOL :: MINIMUM OA LIVE

Minimum Outdoor Air Calculator

ASHRAE 62.1 breathing-zone math — Rp × Pz + Ra × Az through zone effectiveness to a % OA damper floor, split into the DCV-resettable share and the permanent per-area floor.

AirflowRp·Pz + Ra·AzEzDCV Split

TOOL :: DUCT SIZER LIVE

Duct Sizer

The ductulator solved four ways — friction rate and velocity from CFM and diameter, or size to a target friction or velocity — plus Huebscher rect ↔ round, where equal friction is deliberately not equal velocity.

Airflowin. w.c. / 100 ftAltshul-TsalRect ↔ Round

TOOL :: VALVE CV LIVE

Control Valve Cv Calculator

Size a control valve from its flow coefficient — Cv = Q√(SG/ΔP) solved any direction — plus a valve-authority check and a Kv equivalent for metric work.

HydronicsCv / KvAuthorityFlow / ΔP

TOOL :: VALVE AUTHORITY LIVE

Valve Authority Calculator

Authority β from the wide-open valve drop and the rest of the branch, with a good / marginal / poor verdict and a live plot of how the installed characteristic distorts as β falls.

HydronicsAuthority βInstalled CurveVerdict

TOOL :: AFFINITY LAWS LIVE

Pump & Fan Affinity Law Calculator

Scale a known operating point to a new speed or trimmed impeller — flow with the ratio, head with its square, power with its cube. The energy case for VFDs.

Pumps & FansAffinity LawsVFD SpeedImpeller Trim

TOOL :: TRANSFORMER VA LIVE

Control Transformer Sizing Calculator

List what hangs on the 24 VAC secondary, pick the transformer, read the percent loaded and headroom — plus a secondary fuse suggestion sized off the transformer rating.

Electrical24 VACVA BudgetFuse Sizing

TOOL :: VOLTAGE DROP LIVE

Wire Run & Voltage Drop

Copper resistance for the run, then a verdict in the signal's own language — loop supply margin for 4-20 mA, real-vs-imagined error on 0-10 V, degrees of lie on a temperature sensor.

ElectricalAWG4-20 mA LoopLead Error

TOOL :: ELECTRICAL CALC LIVE

Field Electrical Quick Calc

Four field calcs in one: the Ohm's-law wheel (any two of V/I/R/P), single- and three-phase AC power (kW, kVA, kVAR, PF), a motor HP↔kW and full-load-amp estimate, and the NEMA voltage-imbalance check.

ElectricalOhm's Law3φ PowerMotor FLA

TOOL :: WATERSIDE LOAD LIVE

Waterside Load Calculator

The hydronic workhorse q = 500 × GPM × ΔT, solved in any direction — the load a measured flow and ΔT imply, the flow a load needs, or the ΔT a healthy loop should show. Tons ride along.

Hydronicsq = 500·GPM·ΔTMBH / TonsUS / Metric