Using A Two-Column Pressure-Temperature Chart « Digital Zeus™ HVAC Tool & Instruments Journal

Using A Two-Column Pressure-Temperature Chart

January 20, 2008 · 2 Comments

How to Use a Two-Column Pressure-Temperature Chart.

Because the properties of the new zeotropic refrigerant blends are different than traditional refrigerants it’s useful to know how to read a two-column PT chart By Jim Lavelle The pressure-temperature (PT) chart is a valuable tool that service technicians use to check proper system operation. PT charts are most often used for three purposes: to set a coil pressure so that the refrigerant produces the desired temperature, to check the amount of superheat above the saturated vapor condition at the outlet of the evaporator and to check the amount of subcooling below the saturated liquid condition at the end of the condenser.

Read the Rest: http://hvacprotech.forumwise.com/hvacprotech-thread70.html

Categories: Applications · Charts/Diagrams · Diagnostics & Analysis · Guides · HVAC PROTech Forum · HVAC PROTech Technical Archives · Pressure · Temperature

2 responses so far ↓

sam // February 8, 2008 at 5:44 pm

Is there atool can calculate superheat/subcooling and gives the final result?
Digital Zeus™ // February 12, 2008 at 9:47 pm

Not absolutely clear about what you are asking. By final result are you referencing target or actual values?

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