The numbers you need on the roof.
Free HVAC calculators and field reference for techs. Fast on your phone, no login, no app to download.
Calculators
Superheat & Subcooling Calculator
Enter your line temps and saturation temps; get superheat and subcooling instantly.
TSHTarget Superheat Calculator
Target superheat for piston and cap-tube systems from indoor wet bulb and outdoor dry bulb.
DUCTDuct Size Calculator
CFM and friction rate in; round and rectangular duct size, velocity and friction out.
CFMFurnace Airflow from Temperature Rise
Estimate furnace CFM from input BTU, efficiency and the supply/return temperature rise.
µFCapacitor Check Calculator
Measured amps and volts to microfarads, with a pass/fail against the rated value.
AGEHVAC Age by Serial Number
Pick the brand, enter the serial number, get the manufacture date and age.
UNITSHVAC Unit Converter
Tons, BTU/h and kW; °F and °C; psi, kPa and in. w.c.; CFM and L/s; oz, lb and kg.
$/JOBCost per Booked Job Calculator
Compare marketing channels by what a booked job really costs, not cost per lead.
PLANMaintenance Agreement Pricing Calculator
Price a service plan from your real cost per visit, perks and target margin.
FLATFlat-Rate Price Builder
Build a flat-rate task price from time, true labor cost, parts and target margin.
$/HRBreak-Even Labor Rate Calculator
What one billable hour really costs your shop, and what to charge for the profit you want.
TECHSTechnician Capacity Planner
How many techs peak season needs, and what the jobs you can't get to are worth.
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Troubleshoot by symptom
Knowledge base
Cooling
AC and heat pump cooling: diagnosis, refrigerant and charging.
Heating
Gas furnaces, furnace safeties and heat pumps in heat mode.
Mini-Splits
Ductless installs, inverter boards, sensors and error codes.
Airflow & Air Quality
Static pressure, CFM, filters and humidity.
Electrical & Controls
Capacitors, contactors, fuses, boards and thermostat wiring.
Install & Commissioning
Sizing, evacuation and startup done right.
Equipment & Tools
Model and serial numbers, unit age and what to carry.
Codes & Certification
EPA 608, the AIM Act, A2L refrigerant rules.
Running an HVAC Business
Pricing, pay plans, marketing and software for shop owners.