Online PT Chart Calculator

Electrical & HVAC

The ultimate digital PT chart for HVAC technicians. Instantly convert pressure to saturation temperature for R-410A, R-22, R-134a, R-32, and R-454B. High-accuracy, mobile-friendly tool designed for fast field diagnostics and system charging.

How to Use Online PT Chart Calculator

First, select your **Refrigerant Type** from the dropdown menu. Enter the **Low-Side (Suction)** or **High-Side (Discharge)** pressure reading from your gauges. The tool will instantly calculate the corresponding **Saturation Temperature**. You can toggle between **Fahrenheit (°F)** and **Celsius (°C)** or change units between **PSIG** and **Bar** for global standards.

Frequently Asked Questions

What is a PT Chart used for in HVAC?

A PT (Pressure-Temperature) chart is used by technicians to find the saturation temperature of a refrigerant at a specific pressure. This is critical for calculating Superheat and Subcooling to ensure a system is charged correctly.

Does this calculator support the new A2L refrigerants?

Yes! This tool includes data for R-32 and R-454B (Opteon XL41), which are the primary replacements for R-410A in newer high-efficiency HVAC systems.

What is saturation temperature?

Saturation temperature is the point where a refrigerant is changing state (boiling from a liquid to a vapor or condensing from a vapor to a liquid). At this temperature, both liquid and vapor exist simultaneously.

Is this PT chart accurate at high altitudes?

This calculator uses PSIG (gauge pressure) based on standard sea-level atmospheric pressure (14.7 PSIA). If you are at a high altitude, your gauge readings may require slight compensation for atmospheric differences.

What is the difference between Bubble Point and Dew Point?

For refrigerant blends (zeotropes) with "glide," the Bubble Point is used to calculate Subcooling (liquid side), while the Dew Point is used to calculate Superheat (vapor side). This tool provides the saturation data needed for both.