R-Pro › Field cases › Refrigeration systems
Ice Blockage of Expansion Device Confirmed (Moisture Freeze)
Likely causes
Residual moisture from insufficient initial evacuation
Check: Recover all refrigerant
What to do: Recover all refrigerant → Replace filter drier (drier with moisture indicator recommended) → Evacuate to ≤500 μm Hg (minimum 1 hour) → Verify vacuum holds on gauge (vacuum loss = suspected leak) → Recharge refrigerant by weight → Check moisture indicator color after charging (green = dry, yellow = moisture present)
Refrigerant charged with moisture
Check: Replace filter drier (drier with moisture indicator recommended)
What to do: Replace filter drier (drier with moisture indicator recommended) → Evacuate to ≤500 μm Hg (minimum 1 hour) → Verify vacuum holds on gauge (vacuum loss = suspected leak) → Recharge refrigerant by weight → Check moisture indicator color after charging (green = dry, yellow = moisture present)
System left open for too long during service
Check: Evacuate to ≤500 μm Hg (minimum 1 hour)
What to do: Evacuate to ≤500 μm Hg (minimum 1 hour) → Verify vacuum holds on gauge (vacuum loss = suspected leak) → Recharge refrigerant by weight → Check moisture indicator color after charging (green = dry, yellow = moisture present)
Moisture freezes at the expansion device orifice causing blockage. Moisture removal and drier replacement required. If the moisture indicator stays yellow, moisture removal is insufficient. Repeat evacuation and drier replacement.
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
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