EK Dual D5 Top

We tested a lot of D5’s recently including the EK Single D5 Top. This version of the EK Dual top is the series version which means that the first pump outlet connects to the inlet of the second pump. This is the version we would recommend because series pumps are better than parallel pumps (according to martin’s testing here).

As usual the pump arrived in Ek’s pristine packaging:

As usual the top compartment includes the smaller parts and accessories:

Taking everything out we can see a packet of screws, stop fittings and a tool. Two o-rings (this is great if you’ve bought a “bare” version of the D5) are also included, and then the top itself, the clamp and a metal stand:

The metal stand is optional. The volute area is nicely detailed and looks very similar to the single EK D5 top that did well in our previous testing:

The “CSQ” style still only has minimal circles which is a nice balance. There are two ports for both input and output to give you flexibility in hooking it up. The resultant look is simple but classy:

So it looks good but how does it perform?

Testing

For testing we measure the pump pressure gain vs restriction. I.E. We measure pressure across the pump while turning a faucet to simulate loop restriction. We then measure the flow and plot a line charting the relationship between pressure and flow. If you still don’t know what this all means, check out the noob’s guide to reading these plots. So this is what the setup looks like:

Except that the top shown is the Bitspower dual top which we used as a reference. We also used two Laing tops connected with tube as another reference:

The last point of reference is a mathematical construct of what two EK single tops would be like when put in series assuming no efficiency losses. If we plot all of these together then we see this:

It tell us a few things:

– The EK dual top is almost identical in performance to the mathematical construct of two EK single tops. This means that this dual top is about as perfect a performance as you could get.

– The Bitspower dual top performs terribly, far worse than just using the two default Laing tops

– The flow rates are just simply huge because we are using two D5 strongs. Unless you have a ridiculous loop there is no need to run two D5 strongs and you’d be far better off with two D5 Varios at setting 3-4 which would put out numbers much more like the D5 strong at minimum i.e. 1.6GPM on a “medium” loop but without very much noise at all!

Summary

Initially I assumed there would be some compromise for choosing a compact dual top, and there is if you choose the Bitspower top. However the EK is amazing and there are no compromises at all. It has all the performance and features you could want and there is absolutely nothing I can criticize it for.

Gold Award – 10/10

Where to buy: PPCS – $90