Uwell Subtank Shootout: Crown IV vs. Valyrian

UWell Subtank Deep Dive

Uwell subtanks have been gaining popularity because of their innovative designs and excellent build quality. The brand new Crown IV continues this tradition with its new self-cleaning, no leak technology. How does the newest member UWell’s Crown family compare to their mighty Valyrian subtank?

Crown IV vs Valyrian

At the top of Uwell’s subohm tank lineup are two models, the brand spanking new Uwell Crown IV and the powerful Uwell Valyrian. But their price tags are only separated by five dollars ($29.99 for the Crown IV vs. $34.99 for the Valyrian) and they are similarly sized as well. This can make it a bit confusing to determine which of these outstanding tanks is right for you. Today we will help clarify this issue by comparing the most recent addition to Uwell’s top-selling Crown family with their flagship Valyrian tank. We will also investigate the Crown IV’s new self-cleaning, no leak technology. This unique feature is currently exclusive to the Crown IV model of subtank. Will this clever innovation end up being a game changer?

Pyrex Glass Tanks

In standard configuration, both tanks have a 5 ml capacity with straight pyrex glass. The Valyrian’s capacity can be bumped up to 8 ml with a bubble glass fitting that is sold separately. The Crown IV comes standard with a 5 ml straight glass and the package also includes a 6ml bubble glass housing. Both tanks are stainless steel 510 pin and have a 24k gold plated contact.

Plug and Pull Coils

Uwell’s coils use patented “Plug Pull” technology that makes changing coils easy. Neither tank suffers from the lack of mesh coils. The Valyrian and Crown IV both are supported by excellent coil designs that more than hold their own in the flavor and durability department. If you are concerned about sustainable practices or pesticides, you will be happy to discover that both the Valyrian and Crown tank coils use 100% organic cotton.


The Valyrian only has a single coil option: a mighty cloud-bursting 0.15 Ω quad coil head. With a unique parallel coil design for better airflow, it delivers giant, flavorful and smooth clouds. You will want to brush up on your vaping etiquette before unleashing stratocumulus vapor clouds on unwitting passersby. I have used this as my everyday tank and can confirm that it provides outstanding flavor and that its performance is not hindered by the lack of a wide-bore 810 drip tip.

Crown IV

The Crown IV is an upgraded version of the still popular Crown 3 and is available with a wider range of coils than its powerhouse stablemate the Valyrian. All of the Crown IV’s coil options run at lower power settings than the Valyrian, with resistances ranging from 0.2 to 0.4 Ω. The 0.4 Ω especially provides an experience quite different than the Valyrian. It is noticeably more restrictive and slower to ramp up, although a superlative ability to draw out flavor seems to be a common thread throughout the entire Uwell family of subtanks. The Crown IV coils are made from a material that is new to vaping but has been proven durable in Rolex watches: stainless steel SS904L. It is more corrosion resistant and this should prolong the life of the coil, which is an important consideration when mesh coils are not currently offered.

Valyrian Coils

Quad A1 Kanthal Coil 0.15 Ω = 70-80 W

Crown IV Coils

Dual SS904L Coil 0.2 Ω = 70-80 W Dual SS904L Coil 0.4 Ω = 60-70 W FeCrAl UN2 Coil 0.23Ω = 60-70 W

Tale of the Tape

The Crown IV is the shorter and squatter tank, with a diameter of 28mm at the base and height of 54.8mm. The Valyrian measures 25mm in diameter and is 62.3mm tall. The height difference translates into about a third of an inch using the US standard unit of measure. The 3mm diameter difference is not easily discernible but does represent an increase of over 10% in girth. Neither would be classified as a compact or short tank due to the design of their airflow ports and condenser holders.

Ease of Use

Both of these tanks are gorgeous and durable pieces of machinery. They exude quality with tight build quality, pleasing textures, and excellent ergonomics. The build quality is impeccable and all of the connecting pieces snap snugly into place. As mentioned above, the “Plug Pull” coils are great for ease of use and the top fill designs make the business end of both tanks effectively leak proof. Their shared DNA is also evident with the use of 3 bottom airflow ports that form an effective seal when closed.  The Valyrian’s latch mechanism prevented Uwell’s engineers from fitting it with four fill ports like the Crown IV, but the two that it has are a conveniently large 3mm by 8mm and well placed.


In the case of the Valyrian, its hinged top latches smoothly and the tolerances are spot on. The latch button and mechanism on my Valyrian still clicks with authority and functions crisply after months of extensive use. The flip cap is also heat insulated for comfort and ease of use. The Valyrian comes with two drip tips. A range of colors are available if coordinating mod and tank themes is your thing. The mechanics of actually filling the Crown IV and Valyrian differ significantly. The Valyrian has a push button release and a hinged top that opens a bit past 90 degrees to reveal two 3mm by 8mm fill ports. To get at the insides of the Valyrian, you flip it so the drip tip is facing down and twist in the standard counterclockwise direction.

Crown IV

The Crown IV drip tip has dual o-rings, although the Valyrian does not suffer despite lacking this new feature. You can also use your own drip tips, as it is a standard 510 threaded tank. This size of opening is the logical choice for Crown IV, which was designed to emphasize flavor and is less of a vapor-breathing dragon than its more powerful sibling. That said, the Crown IV hits plenty hard when called upon, especially with two lower resistance coil options. The Crown IV has a child proof top that requires a quick 90 degree twist to disengage. It features 4 fill ports. This simplified motion also provides easy access to the tank’s innards. When you want to swap out coils, try out the different pyrex options or perform scheduled maintenance, you actually pull the glass over the top pieces of the mod.

Features and Benefits

Crown IV Self-Cleaning Technology

The Crown IV is an upgraded version of the wildly popular Crown 3 tank. Its most noteworthy feature is self-cleaning, no leak technology. It pulls this feat off by using a unique design that pulls e-juice and condensation in the base through a sealed ring with 3 slots. This moisture is then fed past the past gaps in the coil head. It accomplishes this through the suction created while vaping. Whenever you use the Crown IV it is cleaning itself at the same time. In a field test, I placed about 1 ml of liquid in the base. After vaping for just a few minutes (about a dozen pulls), I checked how the Crown IV was faring. I was surprised to find the liquid had already been removed and the base was nearly bone dry. Uwell’s own testing was surely more rigorous, but the amount of liquid I put in the base was more than would conceivably collect under normal use, especially since the device would be cleaning itself the entire time. Self-cleaning not only means less maintenance but the danger of having nasty, oily, excess liquid spill through the airflow holes is negated. The benefit of this feature is obvious, as Uwell recommends cleaning the Valyrian base every 4-5 fill-ups.

Additional Items Included

Both the Crown IV and the Valyrian come with a practical drip tip guard to prevented unwanted dust and debris from getting into the device. They also come with spare glass, drip tip, coil and a baggy of spare o-rings.

Valyrian Pins

The Valyrian may have only one coil but comes with 3 different interchangeable airflow pins that allow you to customize your vaping experience. As equipped, the tank comes with an “unrestricted” firing pin, which means no long pin at all. The other two are distinctly shaped: the wave and the spiral. The spiral and wave pin both extend about ¾ of an inch above the bottom plate and are positioned dead-center in the center opening in the coil. By extending from the base to the top wire in the parallel coil design, their shape influences the shape and direction of the airflow. The spiral pin is designed for flavor oriented vaping, and actually has a lower wattage recommendation than the other two: 95-105w vs 100-120w. The wave pin is designed to strike a balance between the tighter clouds of the spiral and the unrestricted pins straight blast of vapor. Before dismissing this as a gimmick, consider the fact that this feature has provided you with 2 additional pins to prolong the life of the tank. The pins height and shapes are designed specifically to work in conjunction with the parallel airflow coil in the Valyrian and worked as advertised, although wattage, nic level, PG/VG ratios, e-juice flavor and coil age all have a more significant impact on your Valyrian vaping experience.


So that is the complete rundown on the Valyrian and Crown IV. Both are excellent tanks and which one you prefer will come largely down to personal preference. The Crown IV, especially with the 0.4 Ω coil is going to accentuate flavor over clouds. In real world terms, this translates into less juice burned and fewer 18650 battery swaps. That said, the Crown IV cannot match the Valyrian’s sheer horsepower advantage. No matter what pin you have installed, the Valyrian will hit much harder and draw out plenty of flavor in the process. The unique self-cleaning technology on Crown IV is a great feature and it will be interesting to see if it appears in future evolutions of the Valyrian tank. The Crown IV is the best option you want to enjoy flavorful clouds but keep e-juice consumption to reasonable levels. Plus is has a neat self-cleaning feature. But if you want sheer power, you can’t go wrong with the strong style Valyrian. A final factor is that the coils of the Valyrian are more expensive than the Crown IV’s. Between the lower list price, lower juice consumption, less expensive coils, longer battery life and less cleaning, the Crown IV is the more economical option. But there is always something to be said about power. Your call.