The Hohm Wrecker G2 Intro
Here we go with a review of the Hohm Wrecker G2, the mod that claims to perform temperature control with Kanthal, nichrome and just about any other wire type imaginable. Does it live up to this bold claim? Read on and we provide the answer.
As a taste of what’s to follow, our performance evaluation includes the “Thermocouple of Truth” — real time thermocouple data from inside a functional atomizer to see what’s really going on.
As another quick side note, sure this mod has been on the market for a bit and lots of folks have already taken a look at it. But, Hohm Tech has recently released a firmware upgrade for the Hohm Wrecker G2 that enhances its performance.
Finally, I can say for sure the warning in the Hohm Wrecker G2 instruction manual is to be heeded: “This device is intended ONLY for advanced vapers.”
The Hohm Wrecker G2 Specs and Features
- With FSK chip technology, needs only (2) 20A+ 18650 batteries
- Size: 4.13 x 2.28 x 0.94 in. (105 x 58 x 24 mm)
- Thread Style: 510 connection with full-face push pin with high-tensile strength spring
- Wattage Output: 10W – 151W (also in TC)
- Voltage Output: FSK Intellichips automation
- Temperature Range: 200 oF – 700oF (93 oC – 372 oC)
- Ohm Resistance Range: 0.007Ω – 3Ω
- Temp/Watt Increments: .1-1 watts (WATTS MODE) : 10oF (TEMP MODE) :1 oC (TEMP MODE)
- Coil/Wire Types: Ni, SS, Ti, NiCr, K, & all permutations
Who are these Hohm Tech guys anyway? Well, before we dive in the deep end of the performance evaluation itself, I want to give you a little bit of info about the company.
Hohm Tech is USA based and consists of the two founders, Benjamin Ramalho and Carter Li (pictured above), along with about a dozen other employees. Hohm Tech also has collaborations with several large university department members in disciplines including engineering, computer science, mathematics and project management.
Ben and Carter started out working on specialty vape battery chemistries and they tell me they have successfully developed two proprietary batteries: the Hohm Life and the Hohm Work. While the battery project was underway, they started on the Hohm Wrecker G2 FSK chip.
I’ve had the opportunity to communicate at length with Ben about the FSK technology, but of course most of the details remain proprietary. I can say that Ben has been extremely generous with his time and assistance. He definitely seems to be a real stand up guy who believes in his company and its products.
The Claim of the Mod
What exactly does this mod claim to do? Well, it’s a dual 18650 TC mod that does very good temp control with Ni, Ti, SS and W (tungsten) wire. It has a traditional configurable watt limit adjustment in TC mode as well as an innovative sort of cruise control “Auto+” mode that allows for three basic settings which the mod will use to adjust wattage based on battery charge level and condition.
But the world hardly needs yet another TC mod. The big claim to fame for the Hohmwrecker G2 is its temp regulation abilities with any wire type – including Kanthal and nichrome. To date, no other mod has really been able to successfully do that. It is not claiming any form of “taste control” or a “learning mode” like the Asolo. To quote Hohm Tech: “Measures Kanthal / Nichrome & ALL Metal Temps (RDA, tanks, & any atty’s temperatures can be measured & limited).”
Performance of the Hohm Wrecker G2
An evaluation of a mod with the claims of the Hohm Wrecker G2 has got to include the three objective elements of TC vaping: Ramp to Temp, Temperature Accuracy and Stability of Temp Regulation (RTS).
I don’t do cotton burn tests because I want to vape eliquid, not toast cotton. I don’t really do a whole lot of dry hit testing because I’ve been vaping long enough to know when my atty is starting to run dry, and anyone using this product should be very experienced. What I want for my vape is a fast ramp to temp, and accurate and stable temperature regulation. Let’s see how the Hohm Wrecker G2 stacks up on that measure.
So let’s get right to it – does the Hohm Wrecker G2 actually regulate temperature with Kanthal? It actually does.
To get it going I tried a number of different builds and really had to experiment a lot (a whole lot). It’s not simple or easy in the build or the configuration of the mod. For the build, what I found worked very well was a dripper (Mutation X was handy so that’s what I ended up using), 24 AWG Kanthal, 4.0 mm inside diameter, 9 wraps of each of the dual coils.
I also found that the Hohm Wrecker G2 will regulate temp well, but only when the three variables it works with are set correctly for the build: wattage limit, temperature setting and the FSK Temp Curve value.
I found I had to fiddle (and fiddle and fiddle some more) with those three variables until I was satisfied that it was actually regulating temperature and it was providing the vape that I wanted. Once I had it set up correctly however, the results were amazing.
But don’t take my word for it. Lets’ take a quick look at the “Thermocouple of Truth” profile of the Hohm Wrecker G2 successfully regulating temperature with Kanthal:
OK, what do we have here? This is a chart of actual Kanthal coil temps inside the Mutation X atomizer for a vape with the Hohmwrecker G2.
The vertical or Y axis is actual temperature in degrees C (values along the left side). The horizontal or X axis is time – 8.8 points are plotted each second.
The red line is the coil temp as it ramps up, hits temp, regulates and then cools after the fire button is released. (The flat green line is room temp.)
So what do we see? I pressed the fire button at point 25. The Hohm Wrecker G2 then ramps up to roughly 240 degrees C at about point 43 – so about two seconds for Ramp to Temp. This is slow when compared to most other high end mods.
Next is Temperature Accuracy. The “average’ of the regulated temp produced was about 245 degrees C or about 473 degrees F. The Hohm Wrecker G2 was set to 450 degrees F so the variance was about 23 degrees. This might seem like a lot but it’s Kanthal!
Finally the most amazing result of the bunch: Stability of Temp Regulation. As mentioned earlier, it took a lot of experimenting and fussing but this thing actually will regulate on Kanthal with a stable result. The points from 43 through 98 are the remainder of the vape with the temp staying right in a tight band around 245 degrees C.
I released the fire button right around point 98 and you can see the coil cool – typical exponential decay if you are into math.
To see how amazing this is, let’s take a look at an unregulated wattage mode vape at the same power level:
Now clearly this power setting was excessive for the build but it’s the same power setting I was using when in regulated mode on the Hohm Wrecker G2. In unregulated wattage mode you can see the temperature of the coil zip up to over 300 degrees C and keep climbing, topping out at about 375 degrees C or 707 degrees F – yup, on fire. So the Hohm Wrecker G2 Kanthal temp regulation does work, and surprisingly well.
The Hohm Wrecker G2 interface is a handful. The April 5, 2016 update did “tone down” some of the confusing language on the menu choices, which is a plus in my mind, but this is definitely a device for advanced users only.
To set it up to TC vape with Kanthal, you choose Kanthal as the wire type. This then activates context sensitive choices in the Advanced Menu. In the Advanced Menu, you then choose an FSK Temp Curve Value (from between 0% and 100%). You then choose manual wattage limit mode or Auto+ mode (I strongly recommend manual wattage limit mode, at least at first).
You then set your wattage limit and temperature limit. Whew, are we done yet? Nope.
Then, you need to adjust the interplay between these three variables and the vape you perceive. Hohm Tech recommends slowly increasing the FSK Temp Curve value until you perceive the mod hitting the set temp. This works well – provided that the wattage limit is reasonably within range of what the atty can handle and provided that you are OK with the temp setting being basically a guess based on your perception of the temp.
In sum, there are a lot of choices and permutations in the menus and you will spend a considerable amount of time adjusting them on the path to customizing your vape just the way you like it. The reward: a vape pretty much just the way you like it.
Build quality is very good. Some have criticized its shape as just a box, but it is a well made aluminum box. It’s relatively big, but coincidentally the same size as a box of 100mm cigarettes which it will forever replace. In other words, we former smokers are used to carrying something of about this size in our pockets so that shouldn’t really be an issue.
The finish appears to be anodized and has been durable, even at the corners.
The buttons are plastic but don’t rattle and provide good, “clicky” positive feedback.
Battery door is firmly held by its magnets with no rattle whosoever.
- It does actually temperature regulate with Kanthal!
- Good performance with “traditional” TC wires as well
- Excellent Build Quality and Fit and Finish
- Hohm Tech is a USA based company that is releasing Firmware Updates
- Can be very complicated to use and get working properly
- Slow Ramp to Temp, at least the way I needed to set mine to get it regulating well
- Some don’t like the plain “box” shape but I don’t have any issues with that
- Confusing, almost “silly” terms used for some of the menu options – this has been improved to some degree in the most recent firmware release
If you have always wanted a TC mod but were a dye in the wool Kanthal or nichrome user, this might be the answer for you. Be forewarned, however, that you also have to be willing to futz around with the settings and possibly your build to get it going just right. For folks who enjoy tinkering and a challenge, this is the mod for you.
How does it do it? The details remain proprietary but for all the deep dive tech heads reading this, post up your comments as to how you think the Hohm Wrecker G2 is actually doing it. Get as crazy as you like – electron transit time in the wire measured by phase comparison of fast rise time pulses? Propagation delay affected by temperature and measured by some sort of new feedback multiplication method? A better and cheaper way of measuring infinitesimal resistance changes? What do you think it’s doing?