Water cooling is the pinnacle of desktop thermal management. By using liquid to carry heat away from components to large radiators, systems run significantly cooler and quieter than traditional air-cooled builds.
This guide provides a comprehensive breakdown of liquid cooling, covering All-in-One (AIO) installs, custom open loop plumbing, hard-tube bending, and safety leak-testing.
1. AIO (Closed Loop) vs. Custom Loop
Choose the liquid cooling platform that matches your budget, experience level, and aesthetic preferences:
All-in-One (AIO) Coolers
Pre-assembled, sealed systems containing a CPU water block, pump, tubes, and radiator.
- • No maintenance required (sealed from factory)
- • Easy installation (takes 15-20 minutes)
- • Budget friendly ($60 - $250 range)
Custom Open Loops
Builder-assembled loops combining separate pumps, reservoirs, water blocks, fittings, and tubes.
- • Extreme cooling performance (cools CPU and GPU)
- • Highly customizable aesthetics (colored fluid, bent tubing)
- • High maintenance (requires draining & flushing every 12 months)
2. AIO Radiator Positioning Guidelines
Incorrect AIO mounting causes air bubbles to trap in the pump, leading to annoying gurgling noises and accelerated pump wear. Follow these placement rules:
The radiator sits at the top of the case. Air naturally traps at the top of the radiator, keeping the pump block at the bottom 100% saturated.
If mounting in the front, orient the radiator so tubes exit at the bottom. The pump block remains lower than the radiator top tank, preventing bubbles from circulating back.
Never mount the radiator at the bottom of the case. The pump block becomes the highest point in the loop, trapping all air bubbles inside the pump, resulting in loud noises and pump failure.
3. Custom Loops Anatomy (Pump, Block, Res)
Building a custom loop requires selecting five essential building blocks:
- Water Blocks: Metal plates (usually nickel-plated copper) with micro-fins that mount directly onto the CPU and GPU to transfer heat to the fluid.
- Pumps: The heart of the loop. Standard choices are **D5** (large, high flow rate, running cool and quiet) or **DDC** (compact, higher pressure head, ideal for SFF layouts but runs warmer).
- Reservoir: A tank that holds extra coolant, makes filling the loop easy, and lets trapped air escape. Often integrated directly with the pump (Pump-Res Combo).
- Radiators: Transfer heat from the water to the air. Sizes include 120mm, 240mm, 360mm, and 480mm configurations.
- Fittings: Join components together. Compression fittings are mandatory to prevent tubes from sliding off under pressure.
4. Tubing Selection: Soft vs. Hard Tubing
Your tubing selection affects the building difficulty, look, and durability:
Soft Tubing (Beginner Friendly)
Flexible tubes made of EPDM/Norprene or PVC. Extremely easy to route around tight corners.
Hard Tubing (Premium Aesthetics)
Rigid tubes made of PETG, Acrylic, or Metal. Requires manual heating and bending.
5. Planning & Bending Hard Tubing
If you choose hard tubing, bending requires patient execution:
Lubricate and slide a silicone bending insert into the tube. This prevents the tube from collapsing or wrinkling during the bend.
Hold the tube 4-6 inches above a heat gun set to medium-high. Rotate the tube constantly back and forth until the plastic becomes soft and pliable.
Slowly bend the tube over a mandrel or mold. Hold it firmly in position for 30-45 seconds until the plastic cools and hardens.
Use a tube cutter to cut to length. Use a reamer/deburring tool to smooth both the inner and outer edges of the cut to prevent cutting internal fitting O-rings.
6. Pressure Testing & Leak Verification
Water leaks can destroy expensive electronics. Never boot a system immediately after filling. Follow this safety protocol:
🌊 Liquid Cooling Blueprint Finished!
Planning liquid cooling adds visual appeal and unlocks peak hardware potential. By routing radiators correctly, choosing the right tubes, and pressure testing carefully, you ensure your water-cooled system runs safely.
Head back to the builder to configure your CPU cooling blocks, radiator sizes, and cooling setups!
Next Step: Open the Rig Builder to start planning your custom liquid loop!