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Grainfather Conical Fermenter Owners Thread

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The amber ale I made has WLP007 in it right now as a matter of fact. Ive tried dumping it every day since fermentation started on this batch. It's been coming out like a thick sludge once I can get it moving with shooting co2 up inside the dump valve to break it loose. It's more trub than yeast, very little whiteness of the WLP007 in it.
WLP007 does compact pretty well, but it has never completely plugged itself in the cone for me. Try adding a little headspace pressure (1-1.5 psi) when you dump. This will help push the yeast/trub out the valve and prevent any possibly of a vacuum forming in the headspace during the process. Having a bit of headspace pressure will also prevent any oxidation that would result from air being sucked in through a airlock or the dump port itself. These fermenters are not designed to hold much pressure, so keep the pressures below 1.5 psi. What steps are you taking to leave the majority of solids in the boil kettle and out of the fermenter during transfers?
 

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I had been shooting co2 up through the sample port to get some buffer in the S-bubbler so there wasn't any suck back when I did the dump. It's messy, but at least it has been working. This particular batch is pretty thick with trub.. I forgot the whirfloc tablet in the boil. As far as hot side, I haven't found a great way to avoid getting solids into the conical. I've tried whirlpooling with so-so results. I have a bazooka screen that caused more headaches than it was worth with plugging up.
 

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Whirlpooling and whirlfloc should settle your solids pretty good on the hot side. Make sure you are allowing enough time for the solids to settle before starting your transfer. I usually cool with a CFC immediately after flame out to generate a good cold break. My target temperature is dependent on style, but its always 180F or less. I now whirlpool for 5-10 minutes, just enough to generate an adequate whirlpool that is centered in the kettle. Make sure you do not whip air into the wort at this time. The whirlpool in now stopped and a 30-45 minute dwell is given to allow its full effects to take place. After this time you should be able to transfer your wort with very little solids to the fermenter.

Have you tried pumping the dump valve up and down? How about a different strain of yeast? WLP007 has a tendancy to compact in the cone unlike any other yeast I have used. I has however never compacted to the point where I can not successfully dump it.
 

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I've been using immersion chillers on the kettle, and now in an electric Foundry setup. Are the CFC's that much better?

I haven't had a process down for the whirlpool and allowing it to rest, so that sounds like an added issue as well. The target temperature of 180F is what you aim for with the whirlpool rest right?

As for the valve.. pumping it up and down while smacking the side of the tank is how I can get some movement out of the thick sludge. It has been taking shooting co2 up into that port to blow through it though. The last beer I made was an IPA with WLP001 and had some stuck sludge in the valve, but not like this. I didn't have to shoot co2 up through it to get it to dump.
 

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What's the secret to getting good flow out of the dump valve?

I've fermented two batches in this conical using Wyeast 1272. I've tried dumping at several points during active fermentation as well as after cold crashing. However, I've never been able to get an "extrusion sausage" as mentioned earlier. No matter how slowly and carefully I try to move the valve, I always get a trickle of fairly clean looking beer, followed by a belch of slurry(?). I use 1/2 pint mason jars for collection, and once the slurry settles out, I'll usually have maybe 1/2" of trub, 1/4" of nice looking yeast, and the remaining 80% of the jar is beer.

The relative thinness of the slurry leads me to believe I'm collapsing the cone of trub/yeast each time. Is it possible to control the dump valve accurately enough to keep the layers stratified so I can dump the trub, collect a nice creamy sample of yeast, and not waste too much beer? Or am I expecting too much? Is there some kind of trick to this that I'm missing?
 

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When I can do it, just barely pushing down on that lever ever so slowly, you'll get that thick "sausage" out of there... when it isn't plugged up that is. You have to really finesse that lever so the gravity pressure doesn't explode it out like you're having. I end up having that with mine too because its so thick and plugged up with my current brew inside.
 

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That's pretty much what I expected. Practice makes perfect, I guess.

I may try to see if I can come up with some kind of extension for the dump valve lever. That would make finessing that valve a little less hand-crampy, and also might make it easier to find the sweet spot.

I briefly considered replacing the whole thing with a TC elbow and butterfly valve... until I realized that would leave me with no racking arm. I don't dare to drill a hole for one, because who knows where the electronics are hiding in there.
 

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If you talk the controller plate off, you can see there's access to see the space between the inner and outer walls.
 

franknbeans

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Now I know why I'm not getting anything out of the dump valve.. the oring up in there decided to slip out and the shaft is stuck in place. The orings they use are truly garbage.. I've gone through 3 just putting it together before I ever used it.. now this is 4.
 

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I managed to drop the stir bar from my starter into the fermenter on my last batch. That's probably not helping anything 🤦‍♂️.

It's a shame this valve is such a pain point. It does seem like a clever idea and kudos to GF for thinking outside of the box. I'm not aware of anyone else making a true jacketed fermenter like this at this size and price point.

I wish there was more information out there about it. Googling only brings up the instruction manual from GF's website, a GF-made YouTube video, and this thread. I dunno if GF is really good at SEO, or if we're the only people who actually bought one, lol.
 

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Wow, that oring falling off is a pretty big problem. Are you using the correct size? Is it being installed with a twist in it? I never had problems with the original silicon orings, but i moved away from them after roughly 10 batches because of their O2 permeability. I have been using these for many batches without any problems:


They are definitely provide a more secure fit over the originals because they are noticeably more difficult to install and remove. In fact you might want to try the 2.0 x 26mm and 2.0 x 27mm sizes from the same vendor because the 2.0 x 25mm's might be too tight. The inner diameter of the oring seat is 30mm, so the 26's and 27's might be a better fit. Below is a list of all the orings used in the FV:

Main dump valve: 2.0x25 mm (remember you might want to size up a bit)

Dump valve stem: 1.5 x 7mm (The dump valve uses two of these, one to secure the inlet to the valve, and one between the plastic guide bushings where the valve stem slides against the valves body to open and close the dump part of the valve. These fit pretty damn tight. I usually have to cut them off when changing them. You might want to order some 1.0 x 11.5mm rings to try and see if they offer a bit looser fit. Otherwise at $0.06 a piece it isn't the end of the world if you have to destroy them every time you break the valve down to clean.

Valve stem to ball valve union: AS568-109

Union to ball valve: AS568-111

Ball valve to elbow: 1.5x 17mm

Temperature Probe Seal: AS568-012

All of these orings are EPDM, 70 Durometer. They can be found here:

Metic: https://www.theoringstore.com/store/index.php?main_page=index&cPath=368_2278
AS568: FDA Buna-N O-Rings - We make getting o-rings easy!!
 

franknbeans

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I honestly have no idea how it fell out like it did. It went together fine and everything looked and functioned correctly. I was half tempted to put a TC plug in the top and flip it upside down and pull the valve out to fix it.. but it's about done with a couple days of DH to go, so I'll just let it be.

Wow! I was thinking of taking a set of these to a rubber and seal shop nearby and seeing what they could match with better quality. You sir have saved me some hassle and I thank you!! I'll be ordering these right now.
 

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I managed to drop the stir bar from my starter into the fermenter on my last batch. That's probably not helping anything 🤦‍♂️.

It's a shame this valve is such a pain point. It does seem like a clever idea and kudos to GF for thinking outside of the box. I'm not aware of anyone else making a true jacketed fermenter like this at this size and price point.

I wish there was more information out there about it. Googling only brings up the instruction manual from GF's website, a GF-made YouTube video, and this thread. I dunno if GF is really good at SEO, or if we're the only people who actually bought one, lol.
I almost did that too, and then I started grabbing a magnet off the fridge and holding it on the bottom of the flask as I poured the yeast in. You could use one of those telescoping stick magnets for picking up bolts or nuts that fall down in a hole you can't grab. I always seem to do that with everything, so I have a few of them. :rolleyes: Harbor Freight has them pretty cheap if there's one near you.
 

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I honestly have no idea how it fell out like it did. It went together fine and everything looked and functioned correctly. I was half tempted to put a TC plug in the top and flip it upside down and pull the valve out to fix it.. but it's about done with a couple days of DH to go, so I'll just let it be.

Wow! I was thinking of taking a set of these to a rubber and seal shop nearby and seeing what they could match with better quality. You sir have saved me some hassle and I thank you!! I'll be ordering these right now.
I'm surprised the valve still made a seal without the oring. I wouldn't try inverting the fermenter to try and fix it unless you have a way to fully support the lid along the entire surface that is opposite of the sealing gasket (the surface the four clamps grab). A piece of plywood with a hole cut to the right size and relief cuts made for the four clamps would work. Some 2x4 around the perimeter of this peice would give you the elevation you need for the domed lid once inverted. You would probably want to fix this piece of wood to the fermenter before you try to invert it. Man handling the thing and getting it to sit properly on the mount would be much more difficult. The new main seal will prevent this from happening again. Just make sure the seal goes on without a twist in it. Avoid any kind of rolling manipulation during installation.

I managed to drop the stir bar from my starter into the fermenter on my last batch. That's probably not helping anything 🤦‍♂️.

It's a shame this valve is such a pain point. It does seem like a clever idea and kudos to GF for thinking outside of the box. I'm not aware of anyone else making a true jacketed fermenter like this at this size and price point.

I wish there was more information out there about it. Googling only brings up the instruction manual from GF's website, a GF-made YouTube video, and this thread. I dunno if GF is really good at SEO, or if we're the only people who actually bought one, lol.
Get yourself a strong keeper magnet like this one:


This will prevent you from dropping your stirbar while adding your yeast to the fermenter. You might be able to retrieve your stir bar with a couple of them. One would be used to get the bar out of the cone and near the strait wall of the fermenter. The other would be used to catch the bar at this position and carry it out the 1.5 TC opening in the lid. You would need two, because the fermenter legs would not allow you to maintain a close enough distance to the bar throughout the entire motion. A hand off of the bar would have to be utilized. Your other option is to just use one magnet and capture the stir bar above the floor of the cone. I recommend you do this before you attempt using the dump valve because it is possible the stir bar could get caught in the valve, which would not allow it to close. This would result in a massive mess and a total loss of your brew.
 

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Sounds like you are off to a better start with your current batch. A proper whirlpool followed by a long rest can really help settle the trub, allowing you transfer very little to the fermenter. This is how I have my fermenter setup at the start of fermentation:

View attachment 703387

The blow off cane is from norcal brewing solutions:

Once primary fermentation slows down, I replace the blow off cane with a gas manifold that I made using the manifold body from spikes as a base:

View attachment 703388

This manifold allows me to maintain a slight positive pressure environment inside the fermenter at all times, which enables me to minimize the ingress of oxygen throughout the cold side process. It also makes closed transfers very easy. I also highly recommend getting yourself one of these plant dollies if you want to be able to move the fermenter around with ease:

They fit the legs of the fermenter like they were designed for one another.
Could you list out the parts you added to this manifold? I've been trying to figure out a way to stop suck back when cold crashing on this thing and not deal with mylar balloons and all that mess.
 

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When cold crashing with the grainfather, has anyone tried using the pressure transfer kit for a positive co2 pressure?
 

balbertalli

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I have not tried the pressure transfer kit from Grainfather, but I have a simple 1.5" Tri-clamp to 1/4" flare fitting on its way from morebeer for the same purpose. My next cold crash is scheduled about a week from now. I'll let you know how it goes. I've been happy to use the dual tap valve for transferring, so I didn't really need a lot of the stuff included in the kit. The fitting, TC and gasket was about $22.
 

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The one thing that may help with that kit is micro pressure adjuster and a pressure gauge. It can be adjusted to .1 psi.
It should work.
 

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I have been in contact with grainfather on the new controller. I could not connect it with the gf software with my phone.

I turnes out that a Pixel phone is at android 11. Their app doesn't support the setup. Was able to link it using a tablet.
 

franknbeans

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Dump valve stem: 1.5 x 7mm (The dump valve uses two of these, one to secure the inlet to the valve, and one between the plastic guide bushings where the valve stem slides against the valves body to open and close the dump part of the valve. These fit pretty damn tight. I usually have to cut them off when changing them. You might want to order some 1.0 x 11.5mm rings to try and see if they offer a bit looser fit. Otherwise at $0.06 a piece it isn't the end of the world if you have to destroy them every time you break the valve down to clean.

All of these orings are EPDM, 70 Durometer. They can be found here:

Metic: https://www.theoringstore.com/store/index.php?main_page=index&cPath=368_2278
AS568: FDA Buna-N O-Rings - We make getting o-rings easy!!
So I got these about two weeks ago, and all of them seem to be fitting pretty well. I pulled the dump valve apart completely (I never have before, and it was nasty in the shaft). The original oring between the two bushings was broken when I pulled the shaft out. I got to this part of the oring bag and the 1.0 x 11.5mm orings are way too thin, they leave a lot of play in that union and leak. I now see you said 1.5 x 7mm at first, so this must have been a typo. The 7mm ID ones were out of stock, so I'll look and see if they are back now. I appreciate the time to list all of these. They are much better than the stock silicone ones for sure!
 

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Two things. The grainfather website has the o-ring sets as a kit. These are the soft silicone that comes with the valve. I think they have finally recognized an issue with the cone o-ring and are seeking an EP version as a single item. ($2). Seems like a good upgrade as the silicone in that application is too soft and prone to nicks and cuts.

The connect pro controller on birth the app and the controller itself has a lower limit of 43 °F for cooking. Not sure if it's because of not using the grainfather chiller. Anyone knows how to get around that to cold crash close to 34°f?
Thanks
 

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The connect pro controller on birth the app and the controller itself has a lower limit of 43 °F for cooking. Not sure if it's because of not using the grainfather chiller. Anyone knows how to get around that to cold crash close to 34°f?
Thanks
David Heath has a youtube video (link) where he discusses how to change the lower temperature limit. I believe you need to make a brewing profile with the lower crash temperature and then go to settings and you now have the option to change the lower temp limit.
 

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Could you list out the parts you added to this manifold? I've been trying to figure out a way to stop suck back when cold crashing on this thing and not deal with mylar balloons and all that mess.
Sorry, I remember reading this post but I forgot to reply to it. I will do so in a future post because I am limited on time at the moment.

So I got these about two weeks ago, and all of them seem to be fitting pretty well. I pulled the dump valve apart completely (I never have before, and it was nasty in the shaft). The original oring between the two bushings was broken when I pulled the shaft out. I got to this part of the oring bag and the 1.0 x 11.5mm orings are way too thin, they leave a lot of play in that union and leak. I now see you said 1.5 x 7mm at first, so this must have been a typo. The 7mm ID ones were out of stock, so I'll look and see if they are back now. I appreciate the time to list all of these. They are much better than the stock silicone ones for sure!
The breakdown and reassembly of these valves is a bit of a PITA compared to more standard solutions (TC butterfly valves). It should be part of your SOP if you wish to remain infection free on your future brews though. You should also break down the ball valve because it gets nasty in the void between the two PTFE seals. I wish Grainfather would have used a easier to clean valve in this location. This post of mine discusses the breakdown of the ball valve on the SSBT carbonation stone. The valve is exactly the same internally, it just has a threaded barb end instead of the hex threaded washer. The outer PTFE ball seal is hard to remove the first time, but much easier on subsequent breakdowns of the valve. Take your time and be careful not to damage the seals.


Im sorry the 1.0 x 11.5mm orings did not work out, I recommend them as a possible solution to the very tight fit of the 1.5 x 7mm's which, from my own experience, do work. Both of my valves are currently in service, so I currently can not get the measurement I would need to find a possible better size than the 1.5 x 7mm's at the moment.
 

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I was going to pull that ball valve apart, but got side tracked yesterday before I started brewing. I pulled the ball valve apart on my Anvil Foundry and thought I had cleaned it the last time... nope. It was nasty. I can only imagine how the conical one looks now. 🤦‍♂️ I ordered both the 1.5 x 7mm and 1.5 x 11.5mm orings to see which would fit. I had another set of 1.5mm thick ones and they fit the groove perfectly, so I'm hoping they work better. For now, I just put a couple new silicone ones back in there until these come. The 1.5 x 11.5mm ones were only offered in buna material, so hopefully it works ok.
 

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I bought a Grainfather system around Christmas and brewed my first batch a few weeks ago. I’m very happy with the system; I bought a grainfather, a Grainfather conical, and the glycol chiller. My first batch is a German style lager, currently fermenting at about 10C. The WiFi unit for the fermenter has been running like a charm.... until this morning, when the app indicates it as offline. When I checked on the fermenter, it appears to be connected to the WiFi. Apparently it went offline at about 7:30am. Now, we are in the middle of a winter storm, so maybe the weather is somehow affecting the connection, but has anyone else experienced this issue? I’ve attached a screenshot of the app screen and the wireless unit. The conical fermenter is still working/controlling the temperature; it just appears to be offline for whatever reason. Thanks for any pointers!
 

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I bought a Grainfather system around Christmas and brewed my first batch a few weeks ago. I’m very happy with the system; I bought a grainfather, a Grainfather conical, and the glycol chiller. My first batch is a German style lager, currently fermenting at about 10C. The WiFi unit for the fermenter has been running like a charm.... until this morning, when the app indicates it as offline. When I checked on the fermenter, it appears to be connected to the WiFi. Apparently it went offline at about 7:30am. Now, we are in the middle of a winter storm, so maybe the weather is somehow affecting the connection, but has anyone else experienced this issue? I’ve attached a screenshot of the app screen and the wireless unit. The conical fermenter is still working/controlling the temperature; it just appears to be offline for whatever reason. Thanks for any pointers!
 

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Funny you say that.. I was checking mine last night and saw it lost connection in the app too. Shows it's connected on the controller itself.. very weird.
 

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No idea when it happened to mine. There was a power outage here this past Monday night through mid day Tuesday and that's about the last I see on the tracking graph in app. I have a Tilt linked to it and when I open the app for that, it throws a huge error trying to link itself to the GF cloud tracker.
 

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Hello Everyone,
I own a GrainFather Canonical Fermenter Pro, during my fermentation process I noticed the Rubber Bung is lifting and some Co2 is going out through the space between Rubber Bung and the fermenter.
Do anyone had this issue? How to fix?
I’m using some weight to keep the Rubber Bung on place.

Thanks
 

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I had issues with this, and on glass carboys, too. You want to pull the bung back out, and squirt some star-san on it and around the hole in the lid. The grab a clean towel or maybe a sheet of paper towel and wipe off the moisture left around the hole and the bung.. and then squish that thing down into the hole. As you're pushing it in, spin it back and forth. Leave enough of an edge sticking up that you can grab it if needed to pull out, so about 3/4" or so? Spin it back and forth in the hole until you feel a lot of resistance and it will be stuck there and not pop back out again.
 

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I saw that some people are creating a system where they use co2 from fermentation to purge their kegs. Anybody know how to do this using the GF conical? I have the transfer kit.
 

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When cold crashing with the grainfather, has anyone tried using the pressure transfer kit for a positive co2 pressure?
I have built a wooden cart from some old shelving for my conical, so its about 3 feet above the floor. This allows me to gravity transfer from the small outlet tap so no need to transfer under pressure.
I also capture co2 whilst fermenting directly into a keg (previously used a fermenting bucket to collect).
Blow off tube connected to liquid out post on keg. Gas in post vented to a plastic pot. so only co2 is sucked back when cold crashing or bottling.
When kegging. I disconnect the blow off from the liquid in post & connect it to the gas port on the keg. The gas port is now connected to the top of the conical.
Gravity fill the keg from the small outlet tap on the bottom of the conical into the liquid post on the keg. As beer enters the keg co2 is now pushed out & back into the top of the conical. This results in a totally closed transfer system eliminating any o2 from entering the system.

Short video showing it in action see link below


IMG_7705.JPG
The loop of silicon tube has a small amount of starsan in it which acts as an airlock.
 
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BrewbieVet3

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No idea when it happened to mine. There was a power outage here this past Monday night through mid day Tuesday and that's about the last I see on the tracking graph in app. I have a Tilt linked to it and when I open the app for that, it throws a huge error trying to link itself to the GF cloud tracker.
To close this out on my end, I finally went down just a moment ago and turned off the glycol chiller, unplugged it from the wall, and waited a few moments. While it was off I checked the glycol level on the chiller. It looked a little low, so I topped it off. After waiting a few minutes I then plugged the chiller back in and turned the power on. It immediately reconnected to the WiFi and started up cooling again. The temperature had risen to 16.5C, about the temp for the diacetyl rest. Am keeping an eye on it to make sure the temp doesn’t sink below the target temp of 10C, but so far it looks like a very simple fix of turning it off and back on, with the possibility also of low glycol.
 

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In Grainfather instructions is mentioned the following sentence:”It is good practice to dump dead yeast every 2-3 days during fermentation to prevent the yeast from clogging the valve.
My question is, opening the yeast dump valve we are introducing oxygen to our fermenter....?
What do you think about this?
 

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In Grainfather instructions is mentioned the following sentence:”It is good practice to dump dead yeast every 2-3 days during fermentation to prevent the yeast from clogging the valve.
My question is, opening the yeast dump valve we are introducing oxygen to our fermenter....?
What do you think about this?
I am actually trying to figure out how to do that or whether to worry about it at all. I am about to pull the trigger on a cap for the top that I can hook up a CO2 canister. This will allow me to pressure transfer and allow me to dump and sample without drawing in O2. I was using a "workaround" for closed loop transfer by hooking a hose to the 3 piece airlock. It wasn't pretty, but it worked.
 
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