SLS. 11

 

HVAC refrigerant measurement PSI.

 🧊 1. R22 Refrigerant (Common in old systems)

Mode Pressure (psi) Remarks

Suction (Low side) 65 – 75 psi Normal cooling condition

Discharge (High side) 220 – 260 psi Depends on outdoor temp (40–45°C)

Standing Pressure (System off) 130 – 150 psi Equalized both sides

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🌀 2. R410A Refrigerant (Modern systems)

Mode Pressure (psi) Remarks

Suction (Low side) 115 – 130 psi Normal cooling condition

Discharge (High side) 380 – 450 psi Higher because R410A runs at high pressure

Standing Pressure (System off) 220 – 250 psi Equalized both sides

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🌡️ 3. R407C Refrigerant

Mode Pressure (psi) Remarks

Suction (Low side) 65 – 75 psi Similar to R22

Discharge (High side) 230 – 260 psi Ambient 40–45°C

Standing Pressure (System off) 130 – 160 psi Equalized

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❄️ 4. R134a (Used in small chillers / fridges)

Mode Pressure (psi) Remarks

Suction (Low side) 25 – 35 psi Cooling load condition

Discharge (High side) 150 – 180 psi Depends on ambient

Standing Pressure (Sys

tem off) 90 – 110 psi Equalized both sides