Professional HVAC Tools & Resources
Free calculators and references for HVAC technicians
Calculators
View All →Tonnage Converter
Convert between BTU, kW, RT, and kcal/h
Refrigerant Charge
Calculate charge based on pipe length and tonnage
Electrical Load
Calculate startup current, breaker, and wire size
Pipe Size Selector
Recommend pipe diameter by refrigerant and capacity
Subcool & Superheat
Calculate and diagnose system performance
Why HVAC Toolkit?
Fast & Accurate
Instant calculations with industry-standard formulas
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Use on any device in the field or office
100% Free
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