I just received my boost kit today, I activated it, attempted a roast, and my temp probe readings seem to be wrong.
When the machine was just sitting there after the activation, the temperature showed something like **4. It seems to be a big negative offset, like it's below freeing. It's summer here and probably 25-28C in the kitchen area. That roast failed and went into cooldown. I'm trying 1/3 lb batches. (153g.)
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After the machine cooled down, I noticed that the temperature display values were very unstable, going down to 10C and then up to 22C or so. Every so often, it showed the **4 kind of format.
Maybe the probe has a bad connection? I'm not sure, but it happened just after installing and activating the boost kit.But it feels more like a hardware issue to me, unless the software is subtracting random numbers from the temperature.
Update, When I touched the metal tube that holds the probe, the display flashed off, and it reset.
I just gave the machine a gentle bump by rocking it fore and aft, and it popped up to 24 or 25C. When I move my hand near the chamber - just holding my palm above the Boost ring, the temperature reading decreases to about 20C. When I put my fingers inside the chamber, not even touching the unit, the temperature reading goes down under 10C, decreasing the deeper my fingers go. In other words, the capacitance of my body affects it.
My guess is that there is a bad ground connection in the machine. Touching the chamber wall makes the temperature readout dive down quickly and results in a ##..6 reading.
Update: I got a prompt response from Kaffelogic after filing a problem report. After sharing information, logs, photos, and a video of the problem, they determined that it’s a hardware problem, possibly the thermocouple. Given that I’m in the US, they looped in Eight Ounce Coffee in Calgary, their North American distributor.
Though it was the week after Canada Day and the week of the Fourth of July, I was provided a shipping label. Today, the unit arrived at Eight Ounce.
Of course, the failure is disappointing, but things happen. The good news is that the support network is active and responsive, and people in North America don’t need to ship to and from NZ for service.
Hopefully, the next steps will go smoothly. So far, everything has gone as well as I could reasonably expect, and everybody has been friendly and professional.
I’m looking forward to being able to roast again soon!
Great news. Mike at Eight Ounce in Calgary received the roaster, replaced the thermocouple, determined that it was the problem, roasted two batches, sent me the logs, and will ship the repaired roaster to me tomorrow.
Personally, it’s awesome. Okay, had he flown to my house and provided concierge service, it would have been better, but let’s be real.
The great news for all of North America is that we have “local”, competent, responsive service. If you were worried that you might have to ship to NZ for repairs, that’s not the case. We are covered.
Note that you could have down time. If you are using the roaster for mission critical business, consider buying a backup. Don’t swing that trapeze without a net. My down time wil be about 2-1/2 weeks.
Short of concierge service, everything has gone as smoothly as I could have expected.
Two thumbs up to Kaffelogic and Eight Ounce Coffee!
It's been at least a couple of weeks since the problem has been resolved, and the machine is working flawlessly.
So, what was the issue? The capacitor on the temperature probe input to the circuit board had lifted, making the circuit prone to EMI, and messing up the temperature reading. As an electrical engineer, I'm confident that this was a one-off problem. If the circuit board assembler had other components lift during manufacturing, the affected parts would be random, and would probably have caused a more obvious problem. Kaffelogic tells me that the assembler now has an optical inspection process, so such an error is unlikely in the future.
I'm in the US. The first step was to ship it to Eight Ounce Coffee in Calgary. It's a bit cumbersome going out of the country for repairs, but it worked. I hear that KL will announce a US distributor soon, so that should simplify the repair process here. Eight Ounce was really responsive and communicative, and all the shipping was done at no cost. Unfortunately, after they replaced the thermocouple, they got two good roasts and assumed that the problem was fixed. When I received it, the nominal temperature was now correct, but when I moved my hand near the chamber, the temperature still changed by more than 10C.
I then sent all my logs to KL, they confirmed that something else was wrong with the machine, and they shipped me a new one. I also got the return paperwork and shipped the faulty one back. This was great! They didn't wait for mine to arrive before shipping out the replacement. Again, this was all at no cost to me. Great service from the KL team! A couple days after the old unit arrived there, they found the open capacitor, confirming the problem.
It was weird though. When they put their hand near the chamber, the temp varied by just a couple of degrees. I have carpet and it's dry here, so maybe I built up a stronger static charge. The new unit is nice and stable, and my roasts have been smooth as silk.
The weird thing is that the old machine was never quite right. I had a number of failed roasts with runaway temperatures and under temp failures, but they were random. The old roasts were disappointing, with uneven power applied, so I had tipping, roasts that went way too fast, etc. I had been thinking that roasting was more art than science and had been considering a different roaster. Yes, it roasted coffee, but none of my roasts were very good. The proper roaster is completely different. I never get failures, the curves are smooth and repeatable, and the roasts are world class. I definitely bought the right roaster.
My takeaways are...
* This was a unique problem that is likely to never occur again. It's not a worry for current owners.
* The KaffeLogic and Eight Ounce customer service was top notch. Everybody was professional, responsive, and genuinely wanted to solve the problem.
* There was no out-of-pocket cost to me. KL stands by their product.
* I hate that it happened though. Returns are costly for small businesses, and more so with international shipping.
But here's my big takeaway - If you use this for home roasting, a failure on the roaster is unfortunate, but I can always buy roasted beans to cover the gap. But even with perfect service, it can take time to determine the course of action, ship things out, get the unit repaired, and have it shipped back - especially when customs are in the loop. So, home roasters - be patient.
On the other hand, if you roast for your business, whether it's with KaffeLogic or any other roaster, have a backup plan. Not having your roaster gone for a few weeks could be problematic. Don't be cheap. Get a backup. KaffeLogic's service is great, but it doesn't work miracles. Plan to keep your business running even when service is needed.
Anyway, thanks to all who helped get the problem sorted. Fantastic product and fantastic service!
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