Replacement Oil Cooler For Rotary Screw Air Compressor – Fits Sullair

Replacement Oil Cooler for Rotary Screw Air Compressor – Fits Sullair

How to Choose the Right Replacement
Match OEM part number .
Cooling capacity: kW / HP rating, oil flow, ΔT (inlet ~80–95°C, outlet ~60–75°C).
Connection size & orientation: inlet/outlet port size, flange or NPT, vertical/horizontal.
Material:
Aluminum – air‑cooled, light, low cost.
Copper/Steel – water‑cooled, durable, high pressure.
Pressure rating: oil side ~1.0–1.6 MPa; water side ~0.6–1.0 MPa.

Safety First (Critical)
Stop compressor, press emergency stop, lockout/tagout main power.
Depressurize fully: open drain valves on airend, oil separator, and piping; confirm 0 bar on all gauges.
Cool down: wait 30–60 min to avoid burns (oil temp >90°C).
Isolate fluids:
Oil: close oil supply/return valves; drain oil from cooler and lines into a clean container.
Water: close inlet/outlet valves; drain water (water‑cooled only).
 

Remove Old Oil Cooler
Disconnect oil lines: loosen bolts at oil inlet/outlet; catch residual oil.
Disconnect accessories:
Air‑cooled: disconnect fan motor wires, remove fan shroud.
Water‑cooled: disconnect water hoses, drain plugs.
Remove mounting bolts: take out bolts at base/bracket; lift old cooler out (use hoist for heavy units).
Clean surfaces: remove old gaskets, oil sludge, dirt from flanges and mounting area.

Install New Oil Cooler
Position new cooler: align mounting holes; check inlet/outlet arrow direction (do not reverse).
Tighten base bolts: torque evenly (avoid over‑tightening to prevent core damage).
Install new gaskets: always use new gaskets on all oil connections; apply light sealant if needed.
Reconnect oil lines: attach oil inlet/outlet; torque to specs (typically 25–35 Nm).
Reconnect accessories:
Air‑cooled: reattach fan motor wires, install shroud.
Water‑cooled: reconnect water hoses; open water valves.
Refill oil: add recommended compressor oil to correct level (check sight glass).

Leak Test & Commissioning
Close all drains; open oil valves.
Start in no‑load mode; run 5–10 min.
Check for leaks:
Oil side: all connections, cooler body (no seepage).
Water side (if applicable): no drips at hoses/plugs.
Check temperature:
Normal oil temp: 60–75°C (air‑cooled: ambient +15–25°C).
High temp alarm: >95°C (investigate if triggered).
Full‑load test: run 1–2 hours; monitor temp, pressure, noise.

Common Issues After Replacement
Oil leakage: loose bolts, damaged gaskets, misaligned flanges → retorque or replace gaskets.
High oil temp:
Air‑cooled: dirty fins, fan not running, airflow blocked → clean fins, check fan wiring.
Water‑cooled: low water flow, scaling, wrong water direction → check flow, descale tubes.
Vibration/noise: loose mounting bolts, misaligned cooler → retighten, reposition.