RAPT fridge...I bought 1....Review

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Grmblz

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Talk about reinventing the wheel!
Smoke and mirrors mate, there's already a thread for this sort of sales rubbish, OP was asking for advice not nebulous excuses or theoretical future features, even if they do come from "critical" minds.
Being an early adopter has always come with its risks, but some companies are a much higher risk then others. Caveat Emptor.
 

KegLand-com-au

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How would this additional temp probe differ from the Rapt pill?
Yes the RAPT Pill is a completely separate device. The RAPT pill hydrometer is mainly for checking gravity although it does have a temp probe also.

The separate RAPT bluetooth temperature probe has a stainless steel probe on it so you can insert it into a thermowell or into the malt pipe of your BrewZilla and you will not be able to do this with the RAPT Pill.
 

CJW

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The separate RAPT bluetooth temperature probe has a stainless steel probe on it so you can insert it into a thermowell or into the malt pipe of your BrewZilla and you will not be able to do this with the RAPT Pill.
Cool, when do you expect that to be available? It seems like it is intended to be an important part of the RAPT ecosystem.
 
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It's important to remember that the RAPT fridge will heat and cool the airspace around the fermenter which has veyr little thermal mass. Just because you get the air go up and down in quick succession it doesnt meant that the fermenter (which is a large thermal mass will not do this) so it's completely acceptable for this type of fluctuation to occur.
"Yes - what he said!" The fermenter liquid has a huge lag compared to the airspace around it. Heat flow is small when there's only a couple of degrees difference, the plus or minus 2C of the air will translate into probably plus or minus 0.1C in the fermenter, at equilibrium (*more on this later). And that's one good reason not to run fridge temperature control off of the fermenter temperature - there'd be massive overshoots in the chilling, then massive overshoots in the heating, and hysteresis seen by the fermenting liquid would be the full 2 degrees.
* Downside to the lag: If your fermenter is at say 20C and you throw it into the RAPT and set temperature to 12C, it will take a couple of days to get close to 12C (you've just screwed up the vital first days of that pilsner). Better to kick it all the way down to zero air temperature to accelerate cooling, and take a measurement from the fermenter. When the fermenter hits 12C, then set the fridge temperature to 12C to maintain temperature. Rate of heat flow is proportional to the difference in temperature.

Also another thing that we are working on now is PID cooling as at the moment we only have PID heating as an option.
Wow - PID control of cooling is difficult with an on/off compressor system (it can't ramp power up or down, it's just on or off, and doesn't like rapid cycling). Unless you go to an inverter system (like a modern heat pump airconditioner). Or store cold air (or fluid) and feed a heat exchange system with a PID-controlled pump? But maybe that's the answer, an inverter heat pump that can handle both heating and cooling - but that changes the price significantly. IMHO, I'm not convinced that PID cooling is necessary. Hysteresis and lag are your friends (subject to *).
 

Mysticbrewer

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Yes the RAPT Pill is a completely separate device. The RAPT pill hydrometer is mainly for checking gravity although it does have a temp probe also.

The separate RAPT bluetooth temperature probe has a stainless steel probe on it so you can insert it into a thermowell or into the malt pipe of your BrewZilla and you will not be able to do this with the RAPT Pill.
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mynameisrodney

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Firmware already up to date. Here's a screenshot of the temp. Up to 6 Oct the hysteresis was changed to 1 degree, and after that I reset it to the default 2 degrees for comparison. Any recommendations to reduce the temp swings and improve efficiency would be much appreciated.
Note - I'm cold crashing a cider from now.View attachment 121288
Have you got a way to measure the beer temp as opposed to the air temp? Preferably on a second system not connected to RAPT. Then you can check to see what the actual swing in the beer is.

In terms of efficiency, can you turn off the heating and run it as cooling only? If so I'd be doing this for the majority of fermentation. The yeast should generate enough heat of its own in an insulated chamber. Turn the heating back on if you want to bump the temp up for a diacetyl rest.
 

sp0rk

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The below video is about 3D printers, but what Angus is talking about is 100% applicable to Kegland's business model
Pump out new products ******* CONSTANTLY, and just release new versions or a "new better thing" every few months to hide the rushed, bug/issue riddled products they last released
 
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Grmblz

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Yooo, slaty dog, can you actually point to where Kl have reiterated a product at a monthly frequency/??
Oh dear, a KL fanboi, you're on the wrong thread mate, nav over to KL Q&A for your jollies.
Who claimed a product "monthly"? Read the post pal, and then go to KL Q&A, page one and "read" yes! the whole thing, remembering that many unflattering posts have been deleted, there's still plenty there for an open mind. fwiw it's called due diligence.
Criticism is censored on the KL thread, ie "you are banned from commenting on this thread" OK fair call, as sponsors they can decide who can and cannot post on their thread, but to come onto the rest of the forum with their sales crap, and excuses for immature beta product is not what we are about here, look at the OP #1 and then read how this thread degenerated into an excuse, b/s trail.
Look at how we ended up with the Robobrew 3.1.1, it is now a reasonable product (for the price maybe) but only because of the constant "upgrades" (ka-ching!) from the original, and all-in a very short time frame.
How many suckers will buy into the Brewzilla 4 only to have "upgrades" after the general public has used them and found flaws, will we finally see a Brewzilla 4.1.1?
For anybody that's been on this forum for more than a couple of years it's common knowledge that KL do their beta testing on their customers, good enough for government work ;)
It's actually a real shame that some good ideas are so badly let down by poor implementation, just stand by and watch the whole Rapt thing (which should be brilliant) turn into a complete goat f**k, with "more" stuff coming, and a never ending "update" cycle. @peteru good luck mate.
After all is said and done, there'll be far more said than done, applies to politicians and certain business models.
How dya fleece a flock of sheep? Bring out a new i-phone/robozilla something.
 

wide eyed and legless

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Cool, when do you expect that to be available? It seems like it is intended to be an important part of the RAPT ecosystem.
The website mentions The Pill will be available 15th November but I wouldn't be holding my breath, from what I have heard they are having trouble getting that right too. Then again that won't worry them. Release ready or not.
 

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Firmware already up to date. Here's a screenshot of the temp. Up to 6 Oct the hysteresis was changed to 1 degree, and after that I reset it to the default 2 degrees for comparison. Any recommendations to reduce the temp swings and improve efficiency would be much appreciated.
Note - I'm cold crashing a cider from now.View attachment 121288

Can you please do one thing for me. Can you please hit this setting here and turn the fan off. This will only cycle the fan on with heating and cooling rather than being on all the time. Once you have done this please upload the graph again after you have about 1-2 days of data.
 

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"Yes - what he said!" The fermenter liquid has a huge lag compared to the airspace around it. Heat flow is small when there's only a couple of degrees difference, the plus or minus 2C of the air will translate into probably plus or minus 0.1C in the fermenter, at equilibrium (*more on this later). And that's one good reason not to run fridge temperature control off of the fermenter temperature - there'd be massive overshoots in the chilling, then massive overshoots in the heating, and hysteresis seen by the fermenting liquid would be the full 2 degrees.
* Downside to the lag: If your fermenter is at say 20C and you throw it into the RAPT and set temperature to 12C, it will take a couple of days to get close to 12C (you've just screwed up the vital first days of that pilsner). Better to kick it all the way down to zero air temperature to accelerate cooling, and take a measurement from the fermenter. When the fermenter hits 12C, then set the fridge temperature to 12C to maintain temperature. Rate of heat flow is proportional to the difference in temperature.



Wow - PID control of cooling is difficult with an on/off compressor system (it can't ramp power up or down, it's just on or off, and doesn't like rapid cycling). Unless you go to an inverter system (like a modern heat pump airconditioner). Or store cold air (or fluid) and feed a heat exchange system with a PID-controlled pump? But maybe that's the answer, an inverter heat pump that can handle both heating and cooling - but that changes the price significantly. IMHO, I'm not convinced that PID cooling is necessary. Hysteresis and lag are your friends (subject to *).

I would also agree that PID is really necessary but it's something that customers ask for a lot so we are doing this purely based on customer demand rather than it being a requirement. If we implement PID cooling it will have more to do with turning off the compressor as we approach the set point rather than quickly turning the compressor on and off in quick succession like we do on the heating side.
 

KegLand-com-au

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The website mentions The Pill will be available 15th November but I wouldn't be holding my breath, from what I have heard they are having trouble getting that right too. Then again that won't worry them. Release ready or not.
The stock is in Australia ready to dispactch however we have found a method to further improve accuracy over a larger range and as a result we have decided to finish this last firmware upgrade before we release to the public. I mean it could be released now but at the end of the day we do not want to rush this to market just so we can bring the sales forward by a few weeks so this 15th November date is going to be delayed unfortunately.

If you dont mind me asking you a questions, you say "I have heard they are having trouble getting that right too" where did you hear this? I work at KegLand and have not heard this so interested to know where you get this idea and this information.
 

duncbrewer

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Do you get a certificate with every Rapt purchase ?
" Congratulations you're an Alpha tester "

If the fan isn't on most of the time you will get a thermocline developing in the fridge. The reading will be more stable at the sensor but not necessarily across the whole height of the fridge.
 

wide eyed and legless

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The stock is in Australia ready to dispactch however we have found a method to further improve accuracy over a larger range and as a result we have decided to finish this last firmware upgrade before we release to the public. I mean it could be released now but at the end of the day we do not want to rush this to market just so we can bring the sales forward by a few weeks so this 15th November date is going to be delayed unfortunately.

If you dont mind me asking you a questions, you say "I have heard they are having trouble getting that right too" where did you hear this? I work at KegLand and have not heard this so interested to know where you get this idea and this information.
I will answer your question again, I sold a Tilt on Market place. The guy who bought it has a friend who works at KegLand, I told him he could get three Pills off his mate for what I charged him for the Tilt. That is when he told me that KegLand were having problems getting the Pill right. I am presuming the post was deleted because I mentioned another matter. So I will leave that off for now.
 

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Do you get a certificate with every Rapt purchase ?
" Congratulations you're an Alpha tester "

If the fan isn't on most of the time you will get a thermocline developing in the fridge. The reading will be more stable at the sensor but not necessarily across the whole height of the fridge.
Thanks for the explanation. When we first suggested this solution it was not because there was an issue with the fermenter fluctuating in temperature. It was because the air temperature in the fridge was fluctuating. It seems that we both agree chaging this setting will fix the customers issue.

If you have the RAPT Fermentation Chamber and you want the graph to follow the set temp with the stock probe on the wall then we would suggest that you only cycle the fan on and off with the compressor or heating element. Alternatively if you want the absolute fasted heating and cooling performance then you can put the fan on all the time however you must be aware your graph will fluctuate up and down more to achieve this. Either decision you make the product will do a great job and the core temperature of the fermenter will not fluctuate hardly at all due to the significant thermal mass. In fact it's wort saying the temperature will be precicely between whatever hysteresis settings you use.
 

Reg Holt

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Ahhh here we go again. This is exactly why I rarely bother with this forum anymore.
But you bothered to post.;) I am on here very rarely, a lot less than you. But I think it is a move in the right direction that criticisms can be aired. Teasers about the Rapt fridge have been posted by KL for quite a while now. If there are problems better they are fixed before some disappointed punter spends a grand on one.

As for the Rapt Pill I had a couple on my shopping list thinking they were due for release on the 15th November. Now thanks to this thread I have learned they are still work in progress and won't be released on that date.
 

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