Hailea HC-500A: How it Works
Instead of using one of the afforementioned
undesirable TEC-based methods of cooling water to a sub-ambient temperature, the HC-500A is based around a phase-change cooling unit.
Phase-change cooling is more usually found cooling a single component, typically a CPU, by pumping a sub-0°C liquid refrigerant over the CPU, with the heat of the CPU transferring to the liquid, phase-changing (boiling) it to its gaseous state. This gas is then pumped into a compressor which, with the help of a heat exchanger, phase-changes (condenses) it back to its liquid state to be pumped back to the cooling block to start the whole process again.
This is actually the same cooling system as used in fridges and freezers, but instead of cooling the inside of an appliance by a few degrees, the cooling power of the system is focused on cooling a single PC component, often to sub-0°C temperatures. However, these traditional phase-change coolers are very fussy to use, as you cannot switch on your PC until they reach a preset temperature; they also tend to be extremely noisy.
We didn't want to blow up our HC500A, so here's an exploded diagram instead. Click to enlarge.
The Hailea HC-500A utilises the immense cooling potential of a phase-change cooler to cool liquid passing through it. This liquid can then be pumped around standard PC water-cooling components - this is in contrast to a traditional phase-change cooling system, which requires special temperature-shielded tubing and a special cooling block.
This makes the Hailea HC-500A very easy to integrate into an existing water cooling loop, as it simply replaces your radiator(s). It also means that, unlike traditional phase-change cooling, the Hailea can be used to cool multiple components - just add as many waterblocks to your loop as you need.
Up Close with the HC-500A
As the Hailea HC-500A was originally designed to cool tropical aquariams, it's far too big to install inside any off-the-shelf PC case. The reason it's so large is so that the evaporator can cool a sufficient water per second to keep a 1,000 litre aquariam at the correct temperature. Unlike most PC radiators, which are made of copper, the evaporator in the HC-500A is made from titanium so that it can cope with sea water without rusting.
The evaporator is cooled by a Huayi AE1370YZ compressor that's filled with R134a refrigerant. This compressor is rated at 350W, but due to the huge evaporator, the HC-500A itself is rated by Hailea at 790W (enough to cool 1,000 litres of water to 23°C or 500 litres to 18°C). Given that most PC water cooling loops hold no more than a few litres of coolant, the HC-500A can cool a PC far better than these numbers suggest: as low as 4°C. While our HC-500A can cool monster PC (or perhaps two more modest systems), Hailea
also makes four lower-rated models, plus a monster 1.65kW model.
Most of the inside of the HC-500A is taken up by the evaporator and compressor. Click to enlarge.
Unlike a traditional phase-change cooling system which is always switched on, a processor inside the HC-500A continuously monitors the coolant temperature, switching the compressor on and off as required, so that it's not on the whole time. This is exactly how your fridge works (assuming you're not Ray Mears, that is). The sensor not only saves power, but also means that for lot of the time the HC-500A makes no noise at all. For example, when we set the coolant temperature to 11°C, the compressor only turned on for about 30 seconds every three minutes.
Unfortunately, the compressor itself generates a lot of waste heat, so it in turn has to be cooled. In the HC-500A this job is performed by a huge fan and radiator at the rear of the unit. As a result, it's imperative that you leave plenty of room around the air intakes and exhausts dotted around the outside of the chiller unit.
As the HC-500A was originally designed for use with 1in aquariam tubing, it's not compatible with standard (if there is such a thing) PC water-cooling fittings by default. However, Aquatuning - the European retailer of the HC-500A - does sell suitable 1in to G1/4 adaptors
- Model: HC-500A
- Cooling power: 790W
- Refrigerant: R134a
- Dimensions: 475 x 360 x 490mm
- Weight: 22kg
- Power source: 110-240V AC