I have been trying to figure out a warming flush on a new R58 V2 that would yield repeatability. I have been failing miserably. Using the temperature chart that comes in the R58's manual I set the brew boiler temperature to 106C. As per the manual 106C is supposed to result in 93.5C/199.4F at the group. I am using a SCACE device connected to a FLUKE thermometer. Here is what I have done so far:

1. 1 hour idle. Flush 2oz. Pull simulated shot. Reads 195.1F.
2. 2 mins later. Flush 1oz. Pull simulated shot. Reads 197F.
3. 2 mins later. Flush 1oz. Pull. Goes up to 200F then stabilizes at 199.6F(close to what the chart says)
4. 2 mins later. Flush 1oz. Pull. Same as above and if I pull consecutive shots 2 mins apart they all read 199.2-199.9.

So I figured my first flush of 2oz after 1hr idle wasn't enough to warm the group and that's why I got 195.1 instead of 199.6F. So one hour later I start all over again, but this time:

1. 1 hour idle. Flush 4oz. Pull. Reads 195F. WTF?
2. 1 hour idle. Flush 5oz. Pull. Reads 194.3F. WTF?
3. 1 hour idle. Flush 4oz. Wait 30secs. Pull. Reads 195.3F. WTF?
4. 2 mins later. Flush 1oz. Pull. Reads 198.5F. MEH.
5. 2 mins later. Flush 1oz. Pull. Reads 199.5. Um OK
6. 2 mins later. Flush 1oz. Pull. Reads 199.4 and so on.

I am unable to get to target temperature of 199.4F if the machine has been idle longer than 2 mins. So far flushing volumes between 1oz and 5oz after +2 mins in idle result in readings well below target. I am new to DOUBLE BOILERS, but I feel like I have tried most angles. How do you guys operate your DBs? and what am I doing wrong?

my Brewtus is set for 199F via the PID, this allows for the 11 degree F difference for the boiler and group, this is where WWL set it. If you get 199 95% of the time you will be fine. Mine will drop to 198 but that's about it. If I don't use the machine for longer than 5 minutes I flush the group head about 3 seconds. I also flush the group head before I shut it down fro the night.

I havent scaced my Duetto 2, so.., I just use the basic flush setup outlined in the reviews.

After a long idle period, walk up, flush 4-6oz.
Get out my coffee, tare my scales, purge the grinder. Basically spend a minute or two puttering around getting setup.
Roughly 2 mins after the initial flush, I give her another 1-2oz quick flush.
Grind, dose, tamp.
Pull.

For subsequent shots, if its basically right away another shot, only taking the time to prep another, I dont do any flushing. IF the machine has set still for a couple minutes, I give another quick 1-2oz flush before grinding/dose/tamp.



Only thing I can think of that might translate to your specific setup, is adding a waiting period to the flushes. For the heck of it, you can try what I do if you like. I am NOT measuring how many ounces Im flushing, I have when i first got setup, but two years later, I basically have a "long flush" and a "short flush".

Why not try...

Long idle. Walk up, flush 4oz. Wait 2 or 3 minutes.
Flush 1-2oz. Wait a minute.
Pull your shot.

See how that works for you.

I'll try both your suggestions JmanEspresso and tkenny53 and report back.

F1 wrote:How do you guys operate your DBs? and what am I doing wrong?

Mine are non-E61's, but why not instead of blank flushing use a portafilter with a backflush disc installed and just do one (or two) backflush(es)? If you have to flush as much as Jeff outlined, why have a DB?

Just my $.02

uscfroadie wrote:If you have to flush as much as Jeff outlined, why have a DB?

+1

Interesting observation. I thought the whole double boiler PID is to reduce flushing & temperature uncertainty? With 4-6 oz flushing it may not be so different from a HX...

Maybe you can try increase the PID temp by 5 degree and do a walk-up short flush? Reason being the first temp you've got seems to be *consistently* on 195F.

JmanEspresso wrote:Why not try...

Long idle. Walk up, flush 4oz. Wait 2 or 3 minutes.
Flush 1-2oz. Wait a minute.
Pull your shot.

See how that works for you.

Nope. Just like I thought. Shot read 192.3F. I think that whole routine defeats having a DB. By the way, I have two SCACEs and I double checked just incase one was malfunctioning.

Do you still have your Giotto (HX)? If so, how consistent are you at hitting a targeted temp on that machine?

On a side note, did you buy from a vendor with a Buyer's Remorse policy? If so, I'd definitely contact them to get their take on your machine.

I still have the Giotto and while the temperatures are not as flat as the R58 I was very consistent. As matter of fact it seemed a lot easier to manage the temperatures in the Giotto. I do think there is something wrong with this R58. My luck. I bought it to replace a problematic Giotto and now this. Also the screws in the remote control are too short and this has been confirmed by the dealer who is going to get back to me as soon as they get an answer from the distributor. The screws are to permanently install the remote. I am 99% sure its going back to the dealer.

samuellaw178 wrote:+1

Interesting observation. I thought the whole double boiler PID is to reduce flushing & temperature uncertainty? With 4-6 oz flushing it may not be so different from a HX...

Maybe you can try increase the PID temp by 5 degree and do a walk-up short flush? Reason being the first temp you've got seems to be *consistently* on 195F.

Its not that there is no flushing required, its that the flushing *should* be very simple and require little thought or exactness to get right.(personal comment, based on my experience, its definitely much simpler than learning the flushes of an E61 HX like the Anita or Andreja, two I owned. The flushes change throughout a session as the group and the HX stabalize further. Using a dragon HX, like the Elektra A3, where the flush is always the same every time because its always fully recovered and overheated, is probably just as easy as using a DB, only difference being you DO flush every shot. I can see why those who own dragon HXs dont soon after want to upgrade to an DB like many of us who bought E61 HXs, do.)

Perhaps Im remembering wrongly what was suggested for the Duetto a couple years ago in a pretty long thread about it. Discussing it now, I wouldnt be surprised if Im wrong. Recently Dan reviewed the version 3, Im gonna check right now to see what is mentioned in that review about the warm up flush.

-Seems I made it more complicated for myself than I need too..

HB wrote:In a nutshell, for best temperature stability on the Duetto, do a very short flush if it's been idle for more than 3 minutes and allow 30 seconds for the group to re-stabilize before starting the extraction (e.g., flush before dosing/tamping). If it's been idle for more than 6 minutes, do a longer flush instead (e.g., enough to prewarm an espresso cup). It's really that simple to nail the brew temperature within one degree every time.

You can read the whole post about the temperature stability and how the steam boiler HX feed will affect brew temps in the Bench Review of the Alex Duetto 3

Perhaps there is something wrong with the R58 you have, or you just have figured out the magic touch yet. Idk if the R58 has a steam boiler HX to feed the brew boiler, but if it does, whether or not the steam boiler is on could definitely change things