Delta T Calculator

Calculate temperature split (Delta T) between return air and supply air for quick HVAC diagnostic checks.

This calculator is part of the HVACTools.pro free calculator collection, built for working HVAC technicians. The interactive widget loads when the page hydrates; the content below previews related tools while it loads.

Frequently asked questions

What is Delta T in HVAC?

Delta T is the temperature difference between return air and supply air in an HVAC system.

What is a normal Delta T?

Many cooling systems operate around 16–22°F Delta T, but actual values depend on airflow, humidity, and equipment design.

What does low Delta T mean?

Low Delta T may indicate high airflow, low refrigerant charge, or system inefficiency.

What does high Delta T mean?

High Delta T may indicate low airflow, dirty components, or restricted system performance.

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