DANRENS
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Free HVAC Engineering Calculators

Five sizing tools our sales engineers use every day — actuator torque, control valve Cv / Kv, hydronic flow & ΔT, analog signal scaling and sensor range selection. No sign-up, nothing stored.

Sensor Range & Output Selector

Choose the application and the band you need to measure, and get a standard range, the right sensor element, the output signal to specify and where to mount it — for temperature, differential pressure, humidity and CO₂.

Open selector →

How to use these tools

Each calculator recalculates as you type, so you can see immediately how a wider damper, a lower pressure class or a smaller ΔT changes the result. Everything happens in your browser — no data is submitted or stored.

They are preliminary sizing aids. The damper, valve or coil manufacturer's own published data always governs the final selection; our engineering team is happy to check a selection against the actual duty. See the method notes on each page for the formulas and assumptions used.

Need Help With a Selection?

Send us the schedule or the drawing — we will come back with a sized actuator or valve and the part number.