Today we are looking at the Koolance RP-452×2 (Rev2.0) which is a a dual D5 pump dual bay reservoir combo.  So what does that mean?
DSC_9636 copyWell the easiest way is to explain this is to unpack the box and show what it is.  First off though one thing we don’t show but is important, is to mention just how good Koolance’s packing is.  Almost everything Koolance does is shipped in large amounts of foam, and this is no exception.
DSC_9632 copySo this unit fits into two 5 1/4″ bays usually used for an optical drive or the like.  In addition it can be used to mount 1-2 D5 pumps.  In addition to that, it can also be used as a reservoir (or two) for these pumps.  You’ll note there are some unusual accessories.  These are necessary to enable the larger array of possible configurations.

DSC_9633 copy

So let’s talk about those possible configurations first:

1. 1 loop with 1 pump with 1 reservoir (default as supplied)
2. 1 loop with 1 pump with 1 shared reservoir (both reservoirs connected)
3. 1 loop with 2 pumps in series with 1 reservoir (only 1/2 reservoirs)
4. 1 loop with 2 pumps in series with 1 full reservoir
5. 1 loop with 2 pumps with 1 shared reservoir (pumps in parallel (need a y connector which is not supplied – but then this is not a good configuration)
6. 2 loops with 2 pumps with 1 shared reservoir
7. 2 loops with 2 pumps with 2 independent reservoirs

The main three options we will address are 2, 4 and 7.  We don’t believe the others are really good choices.  Indeed 2 isn’t even a good choice on it’s own because there are cheaper single pump bay reservoirs.  The only reason to roll with option 2 is if you’re looking to future proof.

As the reservoir arrives, it is setup for a single pump to be fitted.DSC_9634 copy

Indeed the secondary pump has a blank to cover the volute.  The ports are closed with stop fittings and the reservoir chamber is not connected to pump one’s reservoir chamber.

As mentioned the main reason to buy this unit is in order to fit it with dual pumps.  The only choice then is whether to use the pumps for one loop and run the pumps in series, or whether to have two independent loops.  In general one loop in series is a smarter choice as you gain pump redundancy while having an easier life filling the reservoir.   In addition a single loops is easier to hook up, maintain and has better cooling benefits due to shared radiators.

Fitting the pumps is easy – four screws secure each plate.  O-rings for the pumps are included so you can buy the cheaper “bare” versions of the pump without the Laing top. Bear in mind these o-rings are slightly different to the Laing sized ones, so you do not want to reuse any o-ring that came with the D5 pump:
DSC_9614 copyIf running two loops then that is the only step to do.  However for series additional steps must be taken:

– fit the supplied u-bend as in the above picture
– remove the stop fitting from underneath a metal plate on the base of the unit:

DSC_9617 copy– Then the last stage is to seal off the 2nd pump from the reservoir.  After all if both pumps had their inputs tied to the reservoir, then one pump would have it’s input and output connected to the reservoir and would be of little help.  To do this we must remove the faceplate cover and window:
DSC_9621 copyThe left chamber then gets its acrylic bleeding shield removed (same as the right chamber) and replaced with an acrylic piece which seals the reservoir from the inlet of the second pump as shown.

Then the faceplate can then be reattached.  However before that, let’s strip the unit completely down to show the rest of the construction.


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