Koolance HX-CU1020V 360mm Radiator Review

1. Introduction2. Technical Specifications3. Flow Rate Testing4. Thermal Testing5. Data Analysis6. Summary7. View All

Introduction

Koolance HX-CU1020V 360mm Radiator Review

The intention of this write up is to provide information and performance data about Koolance’s Slim HX-CU1020V 360mm Radiator. We will be including the test results in the Extreme Rigs Radiator Round Up 2015, however in this review rather than comparing it to all the radiators we made a decision to start a Round-Up just for the slim 360mm rads. Expect our Slims Round-Up to be published in the coming weeks.

I’ll be keeping the review section short and factual, focusing on presenting the performance data compiled through the numerous tests carried out. Firstly a big thanks to Koolance for providing the review sample of the HX-CU1020V 360mm!

What’s in the Box?

The HX-CU1020V (mostly called CUV from here on in the review) sample from Koolance did not have an outer retail sleeve, and I do not think that any of their rads do as this was the same packaging as its bigger brother, the Koolance HX-360XC which we reviewed earlier in the year. They are shipped in what might normally be considered the inner protective box.

Opening the box we see the same layout as the thicker HX version did, which also happens to be the same layout as all HWLabs inner boxing we have seen recently. This is no coincidence, as HWLabs is the OEM for these Koolance rads.

There is no extra protection inside the box, which is unusual as Koolance normally protects everything with large amounts of foam. At one end a flap lifts up revealing a bag with mounting screws for attaching the fans.

Extent of delivery:

• 1 x HX-CU1020V Radiator
• 12 x 30mm (1.18”) mounting screws are included for 25mm thick fans.

Now as my picture clearly shows the screws are in fact shorter than 30mm in length. A custom length 28mm screw set is included.

I have never included photos or info about internal cleanliness previously (although I do include it in my build quality scoring) because cleaning a new rad is just one of those chores which must be done.
I am making an exception with the CUV because I believe it is the dirtiest rinse I have had to date. After 30 or so minutes with a hot water flush, the following pic shows what came out in the first shake and rinse and it took 6 more vigorous shake and rinses to get the thing satisfactorily clean. I even checked that paint had not come from the fittings from the photos taken before hand, but that was not the case – this debris was all from inside, and this is just the first rinse only stuff.

We’re not exactly off to a flying start with this one!!!

Onwards to technical specifications!

Technical Specifications

Technical Data: as listed by Koolance

• Weight: 1.90 lb. (0.86 kg)
• Max Pressure @ 25°C: 2kgf/cm2 (28.5psi)
• Max Temperature: 150°C (302°F)
• Wetted Materials: Brass/Copper
• Fan Capacity: 3 x 120mm
• Fins Per Inch (FPI) 30

Wait – hold up there 30 FPI, that can’t be correct surely?

Dimensions are not listed, but Koolance do provide the following tech drawing.

Dimensions Measured on the Radiator Tested:

The (+2) is the measurement that the ports sit up proud of the casing.

Radiator Core Dimensions:

The core is made up of a single layer of 12 x 1.5mm tubes arranged in a standard U-Flow configuration. The fin arrangement is made of split, non-louvered fins with a 28 FPI count. Yes that is correct – 28 FPI.
This very high fin count shouldn’t be an issue for air-flow as the core is quite thin at just 20mm – but we don’t expect amazing performance with low fan speeds, especially in Push Only.

This picture is a reference which shows a typical U-Flow coolant flow path, where the coolant travels up all the tubes on one side (left in pic) of the rad and then returns down the other side. U-Flow is most easily recognized when the port end has 2 separate tanks, just like the CUV.

The split, non-louvered fins are spaced quite unevenly between the tubes, but with such a high fin count this is to be expected. In the following pics we can see fin counts of 28, 28 and 31, with the majority of my measurements taken being 28 FPI.

Finish and Features

The CUV has a matte black finish which to me seems a bit more like a primer coat than a proper finish.  However I have been assured that this is not the case. Whatever it is the finish gets marked very easily and the sample arrived slightly scuffed straight from the box – with noticeable scuff lines from the cardboard now a permanent feature on the finish.

All visible joints look good, the side panels are solid and overall this rad feels and looks very solid.

Along one of the side panels is the seemingly mandatory branding we find on more and more of our gear. The logo on this sample has been applied slightly crookedly.

The fan mount spacing is the standard 15mm. The scuffing on the side panels I mentioned previously are more easily seen is this photo.

The mounting holes are all located directly above tubes, so thankfully Koolance have chosen to have protection plates fitted on the CUV.

There are just 2 ports in total, 1 inlet and 1 outlet, and these ports are ~2mm proud of the casing.

Extra ports offer potential for dedicated fill or drain ports depending on the installation orientation, so it’s a shame that Koolance chose not to include any.

Unfortunately there is no dedicated fill/bleeder port on the return end either.

So we have a slim radiator with a very high FPI count that has tube protection plates but it has no additional ports. The finish is below average but the overall build is very good.

Let’s see how it performs…

Flow Rate Testing

The Data

As all the testing in this round-up was performed with the exact same equipment, using the exact same methods I have decided to keep each radiators page uncluttered by posting our testing methodology, test set-ups and equipment used in a single location. To see exactly how the tests were carried out, details of the test set ups and equipment used, please head back to the RRU Test Setup page.

Restriction Test

It’s generally agreed that radiators are one of, if not the least restrictive components in the water cooling loop. There are some exceptions however, so this must still be verified through testing:

The above photo is for referencing the restriction test bench The Koolance HX-CU1020V is not loaded so please disregard the data in the picture as it does not relate to it’s test results.

Here is the raw data at the tested flow rates, displaying the measured Differential Pressure across the radiator as flow rate was increased.

Only once before has the Iwaki RD-30 at 24 Volt not managed to achieve the 3.5 gpm maximum flow rate reading on the King Flow Meter. This is a powerful pump and demonstrates immediately that this rad has a very high restriction level.
However numbers in isolation can only tell half the story. By plotting against other components it more easily shows the whole story.

We use a HeatKiller 3.0 CPU block as the reference in these plots for two reasons. Firstly there is no chance of the plot being cluttered by curves overlapping and secondly it gives a reference point against a fairly common loop component of average restriction.

As with all the radiator restriction plots the maximum flow rate displayed has been limited to 2.0 GPM as we suspect there are very few systems that operate above 2.0 GPM. For more information on how to read a restriction plot check out our guide.

This is a first !!!!
Never have we seen a radiator start off and stay above the restriction curve of the reference block. Let’s do some more comparisons before making a conclusion.

The next three plots show the CUV’s restriction level relative to other slim radiators in the test group at 3 different flow rates – what we consider to be low, medium and high system flow rates.

From these tables it would be fair assessment to call the HX-CU1020V a high (or even very high) restriction radiator when compared to the other slims, but before we make that conclusion let’s take a quick look at the restriction levels all our 360 rads at 1.0 gpm.

Previously we had criticized the Nemesis GTS as being unnecessarily high in restriction.  The CUV however gives us a new standard bearer in high restriction radiators.  I think I will have to classify this rad as extremely restrictive, and as such I advise extra planning if intending to use more than one of these rads in a loop as overall system flow rate will be compromised.

Onwards to Thermal Performance!

Thermal Testing

The Thermal Data

Moving on from the restriction test bench the Koolance HX-CU1020V was loaded into the thermal test chamber for a series of tests – consisting of 3 flow rates, each having 3 different fan rpm rates tested. I felt the thermal test data was most important and which you as the reader would be most interested in.

Below is the final data results gathered from at least 2 data logging runs at each flow rate and fan rpm combination. The most stable 15 minute period from each logging run was used and then averaged with the other runs to obtain the data for the table below. A total of 16 temperature sensors were used in the thermal test chamber (8 air in, 2 air out, 3 water in, 3 water out) each take a reading every second and logged via a CrystalFontz unit. The data in the table below is the averaged results of the logging runs which has then been used to create all the plots and tables there-after.

The performance metric of critical importance is the delta between the warm coolant temperature in and the cold ambient air temperature in to the radiator. Given that the system is well insulated and in equilibrium and we know the heat input to the system then we can also calculate a very important number – that is the amount of power required to raise the coolant temperature 1C (or 10C which is more useful reference point).

Let’s take a look at the Delta T results from the tests.

We’re not too concerned about the actual delta numbers here, more so if a trend pattern between fan speeds is occurring. It’s interesting to see the Push Only which is 1.0 gpm draw closer to the 0.5 gpm Push/Pull as the fan speeds increase. Also, what is noticeable is the lack of variance between the 1.0 and 1.5 GPM tests.

Delta T results (as above) are not always helpful when thinking about how many radiators you would need to cool your system. Instead it’s more useful to know the delta/W, or more usefully, the inverse metric of W/delta C.

The metric plotted below tells us how many watts are dissipated by the radiator when the coolant rises 10C above ambient temperatures. (W/10 Delta T):

As expected increasing airflow through the radiator is the primary determinant in changing the radiators performance. This looks like a nice even spread.

This data can now be plotted as a pretty curve so that an end user can interpolate their own fan speed. Note that the extrapolation of the curve is much more sensitive to error than in between the tested range. Let’s exclude the push data for now and come back to it:

The tightly bunched lines is evidence that increasing flow rate is yielding little benefit in performance, particularly at 1.0 gpm and above.

If we now come back to the Push Only data it’s good to compare only the push to push/pull data in an “apples to apples” fashion by only looking at the 1GPM data:

Push only gives around 82% (averaged) of the performance of the Push/Pull 1.0 gpm test results on this radiator. The very straight nature of both the plot lines indicate that the HX-CU1020V has plenty more performance left in the tank, which can only really be unlocked with higher speed/higher pressure (and louder) fans.

In this next plots all three results at 1.0 GPM Push Only are used to produce one curve and we compared the results against all of the slim rads we have tested so far.

Push Only first up:

In Push Only, which we believe is the most likely installation scenario for a slim rad, the performance of the HX-CU1020V is rather weak with low speed fans, but moves into the average range with medium speed fans.

Now let’s compare Push vs Push/Pull:For the Push/Pull comparison chart we have averaged the 3 fan speed test results at each flow rate to produce the curves. Averaging reduces test error of course so this helps further to be sure of our data and is more useful therefore for comparing to other radiators.

The HX-CU1020V is clearly the best performing rad of the group in both the Push Only and Push/Pull with high speed fan assemblies.

 

Now let’s analyze that data some more…

Data Analysis

This first table shows the HX-CU1020V’s Watts/10 Delta Temp numbers in a quick glance chart format.

Using the data compiled from the thermal testing I have compiled the following tables in an attempt to show other ways of how the CUV’s performance varies against itself at the flow rates and fan speeds tested. Effectively these show percentage gains relative to a reference point. It’s an interesting way to show gains/losses while changing a variable.

First let’s focus on 1300 RPM as our reference and see how much gain or loss in performance we get by changing fan speed.

Very large differences here indicate this rad is tuned for best performance with high speed fans.

In the next plot we focus on changing the flow rate with 1.0 GPM as the base line.

With only slight percentage variations when changing the flow rate we conclude that flow rate is not a determining factor for performance on the HX-CU1020V.

Let’s combine both flow rate and fan speed as reference points and have a look at 0.5 GPM & 750 RPM as the reference point.

This confirms what we speculated above, as here we see a big boost from 750rpm to 1300rpm at 0.5 gpm showing weak low fan speed performance and we also see very small gains in the 750rpm column with increased flow rate.

Lastly, we change the reference and choose our center 1300 RPM and 1.0 GPM as our reference point to show both effects concurrently:

So from the data above we can get a very good idea of how the CUV radiator performs relative to itself. But there is a large selection of 360mm radiator models to choose from, released from numerous manufacturers. So, we need to start comparing performance between them.

Push Only Data vs Competition

Let’s focus on the Push Only results for now and come back to the Push/Pull data later. While for Push/Pull we tested three flow rates, the Push Only testing was conducted only at 1GPM in order to save time. For a comparison vs thicker radiators make sure to check out the 2015 Rad Round Up which compares 28+ radiators including the CUV.

Let’s start with 750 RPM and see how it compares to the competition:

The CUV places last in the low speed Push Only rankings with performance a whopping 24% behind the winner. Not a surprising result given the core design, but still, that is quite some margin.

Now let’s look at 1300 rpm:

The CUV does quite well now – 3rd place (just) and only ~6% behind the leader.

At 1850 Push Only the CUV’s dense core structure has gained the performance advantage and taken 1st place.

So as expected the CUV was a poor performer in Push Only with low fan speeds, but really came into its performance zone as we increased the fan speed. We expect the same trend to continue with the Push/Pull results.

Push/Pull Data vs. Competition

Let’s now look at the Push/Pull results and see how the CUV 360 compares. For Push/Pull we have averaged the results from the 3 flow rates at which we tested.

The CUV placed 4th in the low speed Push/Pull. Here we can see a clear winner and a clear loser with the 4 others tightly grouped in the middle.

Let’s move to 1300 rpm:

At 1300 the CUV takes a clear lead over the rest and has ~5% performance advantage of the second place rad.

Now 1850RPM:

At 1850 Push/Pull the CUV 360 is just getting wound up and is the clear winner of this data point. Unfortunately we can go no higher with fan speeds in this test.

So the CUV 360 placed 1st in all 3 of the 6 categories. It has excellent high speed fan performance while has rather weak slow fan speed results. This is of course expected and is due to the dense fin structure.

Now let’s also combine the Push Only and Push/Pull results at the 1.0 GPM flow rate into one plot for each fan speed tested.  This gets confusing quickly so the results are color coded for easier viewing.

Again let’s start with the 750 rpm first:

We are of course just repeating data here in a combined plot format, but it can sometimes be useful in helping to decide if Push Only or Push/Pull fan assemblies may be of more benefit for certain installations, and which rad to choose over another.

From all of test results we created “Average Performance Factor” charts for both Push and Push/Pull and then a combined plot called the “Master Performance Factor”. The radiator with the best cooling ability (W/10ΔT) at each gpm/rpm combo was awarded a score of 100, and each other radiators W/10ΔT result was scored as percentage of the top performer.

This way of looking at the comparison takes away any advantages that a radiator may have at higher or lower fan speeds and looks at an overall average. While this appears fair it does tend to favor those radiators that are all-rounders and those radiators which do very well at high RPM. Most users should be more focused on their specific use case. Check in the Round Up for performance comparisons at every gpm/rpm combo for even more details and cross comparison results.

Here is the HX-CU1020V’s Push/Pull percentage scores at each data point that thermal tests were conducted at and additionally the 1.0 gpm Push Only percentages relative to the winner at each fan speed.

This show the dominance of the CUV at medium and high speed fans in Push Pull. Flow rate did not affect its comparison performance results, placing 1st at each flow rate for these fan speeds.

Then we started averaging the percentage scores at each flow rate giving us the Averaged Performance Factors (APF) of each radiator.

Firstly – the Push Only APF:

While placing 1st in the Push Only high speed fan test, the very weak low fan speed result really dragged down its average score.

Now the Push/Pull APF:

The great results in Push/Pull with medium and high speed fans boosted the CUV into top spot.

Finally the Master Performance Factor which is calculated from the averaged results of all the thermal tests, Push and Push/Pull at all flow rates and all fan speeds.

In the Master Performance Factor comparisons the HX-CU1020V 360mm finishes in second place. The core design is very biased towards the higher static pressure of Push/Pull fan assemblies. The great all round performance of the GTS radiator really did earn the top spot.

Next up – Summary!

Summary

Thermal Performance

Thermal Performance scores are derived from the relevant Performance Factor scores. We set this scale with 72.5% and below as the 0 mark, with each 2.5% increase from 72.5% in relative performance adding 0.5 to the awarded performance score.

The Bold Scores are based on performance comparisons of only the slim 360mm Rads. On the second line is the score which is generated against all the 360mm rads from the complete round up.

Push Only Thermal Performance

• 3.5/5 – Slims Only 360mm rads.
• 1.6/5 – all 360mm rads

The HX-CU1020V 360’s Push Only thermal performance was very weak with low fan speeds, but improved as the fans speeds were increased.

Push/Pull Thermal Performance

• 5.0/5 – Slims Only 360mm rads.
  
• 2.7/5 – all 360mm rads

The HX-CU1020V came out on top with Push/Pull fans with 6 out of 9 first places. Its 97.5 APF score generated a perfect 5 in our summary scoring.

Overall Thermal Performance

• 3.5/5 – Slims Only 360mm rads.
  
• 2.2/5 – all 360mm rads

In all but the low fan speed Push Only tests, the HX-CU1020 performed very well, and its 93.7 MPF score was the second best and resulted in a score of 4.0/5.

I feel that somewhere in the performance scoring that the extremely high restriction level of this rad must reflect in the score, so while I have left the Push Only and Push/Pull results unaltered I am deducting half a point from the overall thermal performance. So what was a score of 4.0 is now a 3.5/5.

Features & Quality – 2.5/5

The HX-CU1020V 360mm from Koolance has a matte black finish which unfortunately scuffs easily and the review sample was already marked when I opened it. While the packaging could be improved with bubble wrap or foam it is the quality of the finish on the rad which is the cause of the issue. I had the exact same concern and issue with the larger version Koolance rad when I unboxed it.

The rest of the build quality is actually very good, and while I mentioned the fins being unevenly spaced, one must remember that it is 30 FPI and that this is quite normal for such a dense fin structure.

At 30mm thick (excluding the ports) it is a slim rad and this is one of the two key features of this rad. It will fit into spaces where “normal” sized rads can only dream of going.
The other most notable physical feature is the extremely high fin count. At 28 FPI it is the highest we have seen and by quite some margin with EK’s SE being the next closest with 21 FPI. With such a dense fin structure you should plan for regular maintenance with this rad and although filters are not my thing, they might be a worthwhile consideration in this instance.

The HX-CU1020V like its stable mate the HX-360XC has only 2 ports which is kind of uninspiring as we love multi-port radiators because they offer more flexibility and options when installing into the case/loop.
Tube protection plates are fitted under the fan mounting holes, which is great because all the holes are located directly above the outside rows of tubes.

The EXTREME restriction level is a cause for concern, and consideration should be made to pump power if considering running more than one of these rads in your loop.

Summary – 3.0/5

The Koolance HX-CU1020V 360mm is a slim radiator which by default means it will never have outstanding thermal performance. When we break down the results and look at the thermal performance of only the slim radiators, the HX-CU1020 performed very well and ranked second overall for performance. It is however extremely restrictive and this lowered its performance score a bit.  However for high speed fans and the ability to dissipate heat in a small space without regard to noise this radiator is simply the best option.  No other radiator comes close to such high performance at high airflows.

As this is a slim radiator it will fit virtually anywhere that has 3 120mm fans spaces side by side.
The build quality is very good but the paint finish is poor and we are missing any additional ports.

At the end of the day this is one of the best performing slim radiators available, but it does require at least medium speed fans to start unlocking the performance potential. The down-sides are extreme restriction levels and a poor paint finish.

Where to buy: Koolance $60