Chiller & HVAC Field Calculators

Free chiller and HVAC calculators for pressure, temperature, vacuum, compression ratio, wet-bulb estimates, and common field service math.

💧 PSI ↔ Feet of Water

Convert between pressure and feet of water column.
Result: —

🌡️ Temperature Conversion

Convert temperature between Fahrenheit and Celsius.
Result: —

🌡️ Delta T Calculator

Find the temperature split between two field readings.
Delta T: —

🏢 Water Hydrostatic Pressure

Estimate static pressure from vertical water column height.
Static Pressure: —

💧 Pump Head Calculator

Calculate pump differential pressure and head from suction and discharge pressure.
Pump Head: —

🧰 Pressure Drop / Head Loss

Calculate pressure drop and head loss across a component such as a strainer, coil, heat exchanger, or chiller barrel.
Pressure Drop: —

⚙️ PSIG ↔ PSIA

Convert gauge pressure and absolute pressure using 14.7 psia as standard atmospheric pressure.
Result: —

🧭 Vacuum Pressure Conversions

Enter one value only. Use this for PSIA below atmosphere, negative PSIG, or inches Hg vacuum.
Result: —

📈 Compression Ratio

Calculate compression ratio using either PSIG or PSIA readings.
Compression Ratio: —

🌡️ Wet-Bulb Estimate

Estimate outdoor wet-bulb temperature from dry-bulb temperature and relative humidity.
Wet-Bulb Estimate: —

Field Notes

PSI / feet of water: This is commonly used for pump head, pressure drop, flow checks, and hydronic troubleshooting.

Temperature conversion: Use this when readings, manuals, or setpoints are given in a different temperature scale.

Delta T: This value is often used for chilled-water load, condenser-water load, coil checks, tower range, and heat-transfer review.

Hydrostatic pressure: Use vertical height from the pressure point to the top of the water column. This is static pressure only and does not include pump pressure, flow loss, or pressure drop through piping.

Pump head: Use suction and discharge pressures taken at comparable elevations when possible. Elevation difference affects the pressure reading.

Pressure drop: Use this for strainers, coils, heat exchangers, chiller barrels, and other components. Higher pressure drop can indicate restriction, fouling, closed valves, incorrect flow, or a measurement issue.

PSIA / PSIG: These tools use 14.7 psia as standard atmospheric pressure. Actual atmospheric pressure changes with elevation and weather.

Vacuum: Inches Hg vacuum is based on pressure below standard atmospheric pressure. Use PSIG-to-inches-Hg-vacuum only for readings below 0 PSIG. Positive PSIG is pressure above atmosphere, not vacuum.

Wet-bulb: The wet-bulb tool is an estimate from dry-bulb temperature and relative humidity. For tower control, commissioning, or performance verification, use a measured wet-bulb reading when accuracy matters.

Need more than quick field math? Chiller Trend turns readings into structured logs, calculated outputs, trends, and defensible findings.

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