A Closer Look – Pump and Control Unit

Hydor (Seltz) L30 II pump

 

The pump included in the WaterChill Power Kit is a modified Hydor (Seltz) L30 II.  This pump in its stock form is quite popular with many liquid cooling enthusiasts and is known for its excellent performance and value.  The Hydor L30 II is a small centrifugal pump driven by a 115 VAC motor.  Like most pumps used in PC water-cooling systems, the Hydor was originally designed for garden pond and aquarium use.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 39

(click to enlarge)

 

Stock Hydor L30 II with ½’ ID hose barbs and Asetek modified Hydor L30 II with push-on fittings.

 

Asetek has modified the stock pump by hard wiring the AC power cord into the a control module and installing threaded push-on fittings into the suction and discharge ports (in place of ½’ OD hose barbs).  This concerns me a little as the small internal passageways of these fittings appear to be potential flow restrictions — particularly on the suction side of the pump.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 40

 

This picture illustrates the hexagonal opening (approximately ¼’ ID), which greatly restricts the water’s flow path.  These same threaded fittings are also used on the reservoir, VGA cooler and Chipset cooler waterblocks. 

 

To measure how much of an affect these fittings have on flow rate, I plotted a PQ curve for the Asetek modified Hydor L30 II and compared it to the stock Hydor L30 II with ½’ hose barbs.  A calibrated, high accuracy flow meter and a calibrated digital pressure gauge were used to take readings.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 41

(click to enlarge)

 

As you can see in the following chart, the flow curve for the stock pump (red) closely matches the published Hydor specs (blue) but the flow capabilities of the Asetek Hydor L30 II (yellow) are significantly lower.  I have to assume this is a direct result of using the push-on style fittings.  It will be interesting to see how much of an impact this will have on overall system performance.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 42

(click to enlarge)

 

 

Asetek Control Unit

 

Another nice feature of the WaterChill kit is the included SafeStart™ Control Unit, which comes pre-wired to the pump’s AC power cord.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 43

(click to enlarge)

 

The control unit is a relay card that automatically turns On/Off the pump and radiator fans whenever the computer is turned On/Off.  An AC power cord adapter and PCI slot bracket are provided for neatly bringing AC power into the computer for operating the pump.  The power adapter plugs into the computer’s power supply AC receptacle and then the power cord plugs into the adapter.

 

WaterChill CPU/VGA/Chipset Water-Cooling System - Cases and Cooling 44

(click to enlarge)

 

A standard 4-pin FDD power connector supplies 12V to the control unit.  On the left is a 3-pin fan header for attaching the two radiator fans and an optional LED header if you choose to connect an LED for operating status.  The jumper to the left of the power connector allows selecting either 12V or 7V for the radiator fans.

 

 

« PreviousNext »