Blichmann BrewEasy

[Gustatorian]

No doubt that a stuck mash would not be good in this system. Like most recirculating systems, without manual intervention, the PID controller would "runaway" and overheat the mash (or at least the wort in the grant). And taking measures to get it back into equilibrium could be a real PITA.

However, crush has a strong impact on any mash system's efficiency. Since it's reasonable to expect better than 63.5% mash efficiency on this system without stuck mashes, I think it's very reasonable to question whether the crush is adequate. Unfortunately when your LHBS controls the crush, not only might it not be adequate, it might vary a lot from time to time.

If you have some pictures of crushed grain, we could probably help you tell whether it's good enough. And you may want to consider investing in a mill.

Thanks for the feedback. I had my reservations about double crushing. I'm brewing again in 2 weeks, I'll send post photos then.

Is a Calcium level over 100 ppm really going to make a huge difference on efficiency. Reviewing my most recents beers, I've kept the Calcium levels between 60-80 ppm. Would increasing that to over 100 ppm really up my efficiency that much?

 

[Hex23]

Thanks for the feedback. I had my reservations about double crushing. I'm brewing again in 2 weeks, I'll send post photos then.

Is a Calcium level over 100 ppm really going to make a huge difference on efficiency. Reviewing my most recents beers, I've kept the Calcium levels between 60-80 ppm. Would increasing that to over 100 ppm really up my efficiency that much?

Double crushing is probably one of the safer things you could do, but in my experience might also have minimal impact. In theory, double crushing can make sure you have less uncracked kernels while not significantly increasing the amount of "flour". But the better option is to have a high quality mill with grain-appropriate gap setting. Don't feel shy about asking your LHBS how they mill. They may even let you choose a gap setting. In any case, it's still a good idea to keep some rice hulls on hand just in case. A good rule of thumb would be 1/2 lb to 1 lb depending on grain bill size and grains used. And, follow traditional rules to help avoid stuck mashes, like letting the grain bed settle before opening the drain and opening the drain gradually.

Usually when talking about mash chemistry's impact on effieiency, the variable to watch is pH. Adding some calcium salts will also affect pH, but I'm not familiar with trying to control calcium ppm directly as a means to help efficiency. It really not a great idea to blindly throw some amount of minerals into your batch without knowing the water your starting with, nor consideration of the grain bill. I'd recommend getting a good spreadsheet or use Brewers Friend to help you with getting a good mash pH. On this system, you'll almost definitely need some acid to get mash pH down. The water primer thread on this site is also a good place to start if you don't want to dive head first into the chemistry.

 

[Gustatorian]

Double crushing is probably one of the safer things you could do, but in my experience might also have minimal impact. In theory, double crushing can make sure you have less uncracked kernels while not significantly increasing the amount of "flour". But the better option is to have a high quality mill with grain-appropriate gap setting. Don't feel shy about asking your LHBS how they mill. They may even let you choose a gap setting. In any case, it's still a good idea to keep some rice hulls on hand just in case. A good rule of thumb would be 1/2 lb to 1 lb depending on grain bill size and grains used. And, follow traditional rules to help avoid stuck mashes, like letting the grain bed settle before opening the drain and opening the drain gradually.

Usually when talking about mash chemistry's impact on effieiency, the variable to watch is pH. Adding some calcium salts will also affect pH, but I'm not familiar with trying to control calcium ppm directly as a means to help efficiency. It really not a great idea to blindly throw some amount of minerals into your batch without knowing the water your starting with, nor consideration of the grain bill. I'd recommend getting a good spreadsheet or use Brewers Friend to help you with getting a good mash pH. On this system, you'll almost definitely need some acid to get mash pH down. The water primer thread on this site is also a good place to start if you don't want to dive head first into the chemistry.

My mash pH has been looking pretty good on my last batches. I use bottled water and manipulate the minerals to get my pH dialed in exactly how I need it. I understand double crushing won't get me too much more efficiency points, I'm just at a loss to understand why I can't even get near 70%.

 

[avmech]

I would not double crush. I've had a stuck mash on this system and it sucks.

 

[scullerkurt]

Efficiency will be low because you never wash the grain with clean water (sparge). You are now where I was a few months back. You can't dial back your mash water volume too much if you have the electric coil in the bk. With gas that may be an option. Even a 1 gallon fly sparge will have a much larger impact than all the other variables discussed. If you control mash temp with rims rocket, you have more water to sparge, mash efficiency will bump to the 80's. Been getting that ever since I made that process change.

Btw, I add minerals to ro water, get brew salt amts per brun water, per desired style. Not sure about 100 ppm ca, I use the more typical water profiles in brun water, nothing fancy.

 

[Hex23]

My mash pH has been looking pretty good on my last batches. I use bottled water and manipulate the minerals to get my pH dialed in exactly how I need it. I understand double crushing won't get me too much more efficiency points, I'm just at a loss to understand why I can't even get near 70%.

You should also try to rule out measurement error. The main sources of that would be pre-boil volume measurement and SG. I saw someone recently (in this thread?) claiming their BM sight glass was off. And if you're using a refractometer, make sure to check the calibration and also apply a wort correction factor - or just use a well calibrated hydrometer near its calibration temp. Also, even if your pre-boil volume is correct, if you could still drain more wort, that's another source of efficiency loss.

Otherwise, since you've got pH under control, crush is really a good next place to look.

Only other questions I can think to ask would be have you independently checked the mash temp (e.g. using the MT dial thermometer) and are you also following the raking instructions and balancing water such that you have a couple inches of cover over the grain bed?

 

[Hex23]

I saw someone recently (in this thread?) claiming their BM sight glass was off.

Oh, that was you

I don't follow everything you say about how you deduced it's off and what volumes you're actually using, but one thing I noticed is that you're using buckets to get accurate volumes. If you're talking about standard 6.5 gallon plastic fermenting buckets and using the markings on the side, those aren't known to be very accurate.

If you carefully explain again what measurement system you're trusting and which direction the bias is, we could tell if that could even be the cause of your apparent efficiency problem - or if it's even worse than you think

Edit: Ok, read your reasoning again and I think I understand it better. If you're fermenting in the same bucket you're using to measure strike water, then that's consistent with the notion that you're bucket is off (under-measuring) and you really do have more pre-boil volume and volume into the fermenter than you think, thus underestimating your efficiency.

 

[scullerkurt]

Oh, that was you

I don't follow everything you say about how you deduced it's off and what volumes you're actually using, but one thing I noticed is that you're using buckets to get accurate volumes. If you're talking about standard 6.5 gallon plastic fermenting buckets and using the markings on the side, those aren't known to be very accurate.

If you carefully explain again what measurement system you're trusting and which direction the bias is, we could tell if that could even be the cause of your apparent efficiency problem - or if it's even worse than you think

Edit: Ok, read your reasoning again and I think I understand it better. If you're fermenting in the same bucket you're using to measure strike water, then that's consistent with the notion that you're bucket is off (under-measuring) and you really do have more pre-boil volume and volume into the fermenter than you think, thus underestimating your efficiency.

Agreed. I made marks on my bucket, bk, and mt by putting in one gallon of water at a time.

 

[Danam404]

Those of you who are still in the 60's for efficiency... Add two or three pounds of 2-row to your recipe. Obviously the ideal would be to hit 70%, but as you are fine tuning your process, the $3-$4 worth of grain will be you where you need to be gravity-wise. Beats watery beer!

 

[scullerkurt]

I'll also suggest using dme or lme to hit your og

 

[Gustatorian]

You should also try to rule out measurement error. The main sources of that would be pre-boil volume measurement and SG. I saw someone recently (in this thread?) claiming their BM sight glass was off. And if you're using a refractometer, make sure to check the calibration and also apply a wort correction factor - or just use a well calibrated hydrometer near its calibration temp. Also, even if your pre-boil volume is correct, if you could still drain more wort, that's another source of efficiency loss.

Otherwise, since you've got pH under control, crush is really a good next place to look.

Only other questions I can think to ask would be have you independently checked the mash temp (e.g. using the MT dial thermometer) and are you also following the raking instructions and balancing water such that you have a couple inches of cover over the grain bed?

Doing all of those things, although I'm interested if anybody here has any input on raking. I feel like I'm moving around the top 2/3 of the mash every 15 minutes. How long do each of your rake sessions last, I'm merely pushing things around for 10-15 seconds...

 

[Gustatorian]

Agreed. I made marks on my bucket, bk, and mt by putting in one gallon of water at a time.

You mind sending a photo of how you marked your BK and MT? Also, did you just use a 1-gallon pitcher to get an exact 1 gallon measurement?

 

[Goldenboy]

To answer the question of how I clean, first check out the picture of my system (which hopefully shows up, it's a pic when I'm doing a fly sparge).

With higher grain bills (Belgian beers) I was struggling with stuck mashes. Because you need to keep the electric coil fully submerged in the BK, you basically get handcuffed on your mash thickness in the MT. I did rice hulls and other tricks, but I still struggled with stuck mashes when grain bill was high. I also really couldn't stand how long the temperature control (in auto) took to hit setpoint. So besides the handcuff that I mentioned, you also have a greater volume of water that you need to heat in the BK, so I decided to get rid of the lag time (due to the volume) by controlling my mash temp with the RIMS rocket, plus I can run thinner mashes. I also wanted to use the hopback feature, which I just did yesterday on an IPA using homegrown hops.

For my first batch with the RIMS rocket, the temperature control was very cyclical. Next batch I spent a hour or so trying to figure out the temperature controller settings before I brewed, I did some digging online and found a delta temperature controller user manual that looked VERY similar to the Blichmann temp controller. I noticed the temp controller was programmed to ONLY use gain, no Integral or Derivitive (all P, no I or D). Temperature control systems are one of the few loops the typically use P, I, and D (most loops only use P and I). I didn't have they instrumentation and control loop tuning toys I had when I was an engineer, so I relied on the auto tune feature (look at your temperature controller, see on the lower left where you see AT...that lights when the controller is performing an auto tune). Very snappy controls after auto tuning, without overshoot as the other attached picture shows (hopefully you can see the pic).

Onto the cleaning question. After I sparge, I unplug the RIMS rocket and relocate the plug into the BK. (My brew day is slower than it could be if I spent $500 on another TOP controller, I could boil while I sparge, but for an additional 30+ mins on brew day (=1 more beer to drink) I'm cool with a slightly longer brew day.)

I put the HLT away, I dump the MT and hose out as others mentioned. I'll pull out the RIMS rocket (real easy to clean manually) and replace that with the HX. I put PBW in the MT, then pump room temp PBW from MT through the pump, HX, flow meter (I have the full TOP), RTD and back to the MT. Run PBW 15 mins, dump PBW into a bucket for next brew day, water rinse the system, then run Star San for 15 mins. I dump the star san into another bucket, loosen up fittings to drain starsan from HX, pump, etc...then you're ready for chilling. I whirlpool when I chill my wort, when I first turn on the pump, I'll pitch a few hundered mls of wort, I figure it probably has a good bit of StarSan that I didn't drain.

In using the TOP to whirlpool, I find it to be pretty handy because you can see your wort temp leaving the HX on the RTD, and you can see the temp in the BK. My city water temp is real warm (mid 70's) so I use my former immersion chiller to pre-chill the city water in two 20 lb bags of ice (ice is in a cooler).

One interesting thing that I noticed now that I don't use the BK for "K-RIMS," there is WAY less crud stuck on the BK heating element. My LHBS owner, whom is also a beer judge, thought my beers had a carmalized taste to them, since going to RIMS rocket, he doesn't taste that anymore, FWIW.

Oh, after brew day is run, I'll do the official 160 deg F PBW cycle, water rinse, and acid sanitize.

You now have read a summary of 15 batches of knowledge using the breweasy which I purchased in late May. While the RIMS rocket added more expense to an already pricy system, I'm really happy with the control, flexibility, and efficiencies I'm getting now. The beer of course tastes great, but I thought my beers tasted great when I was an extract brewer. We'll save the AG vs extract debate for another day

I see you use a HLT. I've been thinking about getting a RIMs-Rocket. If so, what do you think about possibly using the brew kettle to heat the sparge water and then running the heated water through the MT back into the brew kettle--that is assuming the recipe has enough water to cover the boilcoil in the brew kettle?

So, when the mashout is complete. Switch the hose to the pump to the brew kettle where the sparge water is heated and then cycle for 10 minutes or so.

 

[scullerkurt]

Only issue is you want to maintain you liquid level constant when sparging, the autosparge obviously works great for that. Your goal on the sparge is to have "slug" flow of sparge water that strip wort from the grain. You'll need to have wort leaving the mt while the hlt is maintaining level on the mt. You could drain from the mt into a large pot, which you can dump into the bk once all the water is gone.

With my setup, once the hlt is emptied, I typically have enough wort in the bk to plug in and turn on the boilcoil. I'll get my wort close to boiling by the time sparging is complete, so little wasted time.

Kurt

 

[DurtyChemist]

Efficiency will be low because you never wash the grain with clean water (sparge). You are now where I was a few months back. You can't dial back your mash water volume too much if you have the electric coil in the bk. With gas that may be an option. Even a 1 gallon fly sparge will have a much larger impact than all the other variables discussed. If you control mash temp with rims rocket, you have more water to sparge, mash efficiency will bump to the 80's. Been getting that ever since I made that process change.

Btw, I add minerals to ro water, get brew salt amts per brun water, per desired style. Not sure about 100 ppm ca, I use the more typical water profiles in brun water, nothing fancy.

If this was true no one would hit 70% with BIAB. I can without doing a double crush and I don't even own my own mill. I also use BruN water and have it filled out from my local water supply lab report.

I would suggest checking the mash pH and trying a SMaSH recipe. The Breweasy is a BIAB setup on steroids with mash recirculation. If you know your water content it can make the mash a better environment for the enzymes on top of your pH. I ALWAYS take a pre-boil gravity reading and cool it to see what I'm at before the boil. This seems to help me maintain my consistency. I use Brewers Friend as my guide.

After that I'd consider stirring the entire grain bed and eliminating any stratification that may be happening. Instead of raking for 15 seconds make it 3-4 minutes and try and get the grains from the bottom of the mash tun to the top. You could have channeling which could also explain your low efficiency. After that I'd consider buying a moster mill 2.0 and hopper and crushing my own grains compared to the brew shop. Maybe you can ask them what their gap is set at and find someone locally that will let you use their grain mill if you're in a club.

 

[scullerkurt]

What efficiency are you talking about? 70% conversion, or 70% brewhouse? I'm talking about the conversion, I use brewers friend as well. My conversions are upper 80's low 90's. Brewhouse is in the mid 70's. Prior to my process changes brew days were longer and efficiencies weren't anywhere near what I'm getting now. My conversions used to be in the low 70's, brewhouse in the low 60's.

I would use caution mixing too much. When you mix, notice how the level drops in the sight glass? My experience is as the mash time progresses, stir the upper 1/3 of the grain bed but keep an eye on the sight glass. If you see significant drops in level, be careful. I don't need to worry about that as much now that I'm able to run thinner mashes.

If you want an efficient, responsive system, I can assure you adding the rims rocket will be a significant process improvement, just make sure you retune the TOP controller.

 

[Gustatorian]

What efficiency are you talking about? 70% conversion, or 70% brewhouse? I'm talking about the conversion, I use brewers friend as well. My conversions are upper 80's low 90's. Brewhouse is in the mid 70's. Prior to my process changes brew days were longer and efficiencies weren't anywhere near what I'm getting now. My conversions used to be in the low 70's, brewhouse in the low 60's.

I would use caution mixing too much. When you mix, notice how the level drops in the sight glass? My experience is as the mash time progresses, stir the upper 1/3 of the grain bed but keep an eye on the sight glass. If you see significant drops in level, be careful. I don't need to worry about that as much now that I'm able to run thinner mashes.

If you want an efficient, responsive system, I can assure you adding the rims rocket will be a significant process improvement, just make sure you retune the TOP controller.

Definitely plan on doing this! Send more photos when you get the chance!

 

[Danam404]

After a year of service (wow), the BrewEasy has gotten a full deep clean and polishing. Here's some shots of my brewery. I have the system hooked up to a retired washer/dryer station which works out great... hot water, cold water, and a drain make for a very convenient brew station. The hot water cuts quite a bit of time getting to strike temps, and the drain is great for the used chiller water. Not to mention the 220v plug.

A tip for shining up your stainless goodies: rub a light coat of Boos Butcher block oil (I've also heard olive oil works). It will keep your equipment incredibly shiny, and resists fingerprints and soiling. I was skeptical when I heard it but it works awesome!

Here are pics of my brewery.

And as always, check out my brew easy videos on youtube!

Brewday Timelapse: [ame]https://www.youtube.com/watch?v=PqiQ--VzzaA[/ame]
Getting the most out of your BrewEasy: [ame]https://www.youtube.com/watch?v=gDJLzAXZbFw[/ame]

 

[chigundo]

Thinking about running this as a breweasy clone.View attachment ImageUploadedByHome Brew1445473490.931306.jpgView attachment ImageUploadedByHome Brew1445473503.136576.jpg

 

[chigundo]

The Chapman insulated MT will have an autosparge, and instead of an orifice, I'll throttle the flow from the MT via a ball valve. The MT will enter the BK via that connection at the top of the BK, which is shown in 2nd pic. Do you think this will work? It'll be gas fired using a TOP.

 

[psymonkey]

After a year of service (wow), the BrewEasy...

Hey man - I wanted to thank you for the video you posted on getting the most out of your breweasy. It made a tremendous difference in my enjoyment and love of the system.

The most useful tidbit was that you didn't stir the mash on mash-in. I hadn't considered not doing that, being used to stirring profusely in my old cooler-MLT.

Stirring was causing grains to get forced through the false bottom, which in-turn clogged my little orifice which in-turn caused all sorts of problems to manifest. That simple change has resulted in several smooth brew days. So thank you!

 

[jmitchell3]

The clogging was post boil as all the hops and trub got picked up on the way out of the kettle.

I've done 3 or 4 batches on my BE system, usually begin to recirculate boiling wort for the last 10 minutes of the boil. I use a blichmann hopblocker. The issue I've had is air in the line causing minor cavitation of the pump...further restricting the outflow valve has resolved that problem.

I've not had any issues with hops or trub clogging the pump at all. Haven't done a double IPA yet though either...

 

[Gustatorian]

I've done 3 or 4 batches on my BE system, usually begin to recirculate boiling wort for the last 10 minutes of the boil. I use a blichmann hopblocker. The issue I've had is air in the line causing minor cavitation of the pump...further restricting the outflow valve has resolved that problem.

I've not had any issues with hops or trub clogging the pump at all. Haven't done a double IPA yet though either...

Make sure to open both valves, pre and post pump, before turning on the pump. I always had issued with cavitation/unable to get wort moving until I did this.

 

[Danam404]

pics arent loading from my last post, lets try this:

 

[jmitchell3]

Make sure to open both valves, pre and post pump, before turning on the pump. I always had issued with cavitation/unable to get wort moving until I did this.

Yeah, definitely. In this instance, I think it has been caused by air from the boiling of the wort. It does not appear to be a problem when priming the pump...

 

[jmitchell3]

pics arent loading from my last post, lets try this:

Looks good!

 

[Gustatorian]

Brewed yesterday...still having efficiency issues. After reading this forum (several times), I think it has to do with the grain mill setting. To preface this, I have no control over the mill setting, it's done at the LHBS and they won't change it. They've offered to double-crush and add rice hulls, but most of you guys have said that it's a bad idea/would get a stuck mash, so I opted against that. I've attached 2 photos of what the grain looks like. Let me know if you think the grist isn't fine enough.

Also, when I brew 5 gallon batches, I'm having issues balancing my water between my 15 gallon MT and 20 gallon BK still. That issue being keeping my boil coil underwater so that it doesn't scorch. I've had portions of it out of the water a couple of times, scorching the coil (creating the smell of burnt toast) but never really affecting the beer's flavor. Has anybody ever had a beer ruined due to the coil scorching? Also, has anybody ever ruined a boil coil? When I go to clean it later, there is some black material on the coil, but it always comes off fairly easily.

Also, does anybody have an tips on using the Autosparge? It's always a balancing act that I have to constantly watch during the mash, altering the flow valve after the pump and the valve from the MT to BK. Once I get the balance, I don't have to worry about the boil surfacing. Any recommendations on using the Autosparge would be helpful! And SkullerKurt, I'm probably going to end up buying a RIMs rocket, probably the easiest way to fix this whole situation.

 

[scullerkurt]

Sorry I haven't posted, I've been busy designing my own commercial brewery, just signed a lease. Once I set up my lab scale brewery I promise to get pictures and video to share with ya'll.

 

[jmitchell3]

Crush looks decent. Maybe even on the finer side of moderate. Do you measure your mash pH? What are your calcium levels?

Brewed yesterday...still having efficiency issues. After reading this forum (several times), I think it has to do with the grain mill setting. To preface this, I have no control over the mill setting, it's done at the LHBS and they won't change it. They've offered to double-crush and add rice hulls, but most of you guys have said that it's a bad idea/would get a stuck mash, so I opted against that. I've attached 2 photos of what the grain looks like. Let me know if you think the grist isn't fine enough.

Also, when I brew 5 gallon batches, I'm having issues balancing my water between my 15 gallon MT and 20 gallon BK still. That issue being keeping my boil coil underwater so that it doesn't scorch. I've had portions of it out of the water a couple of times, scorching the coil (creating the smell of burnt toast) but never really affecting the beer's flavor. Has anybody ever had a beer ruined due to the coil scorching? Also, has anybody ever ruined a boil coil? When I go to clean it later, there is some black material on the coil, but it always comes off fairly easily.

Also, does anybody have an tips on using the Autosparge? It's always a balancing act that I have to constantly watch during the mash, altering the flow valve after the pump and the valve from the MT to BK. Once I get the balance, I don't have to worry about the boil surfacing. Any recommendations on using the Autosparge would be helpful! And SkullerKurt, I'm probably going to end up buying a RIMs rocket, probably the easiest way to fix this whole situation.

 

[Gustatorian]

Crush looks decent. Maybe even on the finer side of moderate. Do you measure your mash pH? What are your calcium levels?

Always measure PH, this batch hit spot on at 5.5. Calcium was at 142 ppm.

Do you guys open your valve on the T.O.P fully? I'm worried my efficiency is low because I don't have enough fluid moving within in the MT. Also curious to see how people rake their grain...maybe I'm not raking vigorous enough...

 

[jmitchell3]

Always measure PH, this batch hit spot on at 5.5. Calcium was at 142 ppm.

Do you guys open your valve on the T.O.P fully? I'm worried my efficiency is low because I don't have enough fluid moving within in the MT. Also curious to see how people rake their grain...maybe I'm not raking vigorous enough...

I just do what DanaM says to and rake the top third or so every 15 mins. not much, just enough to even it out and prevent channeling.

Was 5.5 pH at room temp or mash temp?

 

[Gustatorian]

I just do what DanaM says to and rake the top third or so every 15 mins. not much, just enough to even it out and prevent channeling.

Was 5.5 pH at room temp or mash temp?

At RT, at mash temp, I'm around 5.25-5.3

 

[jmitchell3]

At RT, at mash temp, I'm around 5.25-5.3

Dunno, everything looks to be on target then. Might be worth doing a lower gravity recipe and have the lhbs double-mill your grains and see what happens...

 

[Gustatorian]

Dunno, everything looks to be on target then. Might be worth doing a lower gravity recipe and have the lhbs double-mill your grains and see what happens...

Does anybody have any experience with double-milled grain and the BrewEasy?

What if I pack with a ton of rice hulls?

 

[jmitchell3]

Does anybody have any experience with double-milled grain and the BrewEasy?

What if I pack with a ton of rice hulls?

I'd say if you can fit em, throw in 2-3 lbs of rice hulls and you should have a fighting chance of a good result.

 

[Danam404]

Does anybody have any experience with double-milled grain and the BrewEasy?

What if I pack with a ton of rice hulls?

I do not believe a double crush is worth messing with on this system... Generally the crush is about the last place you'll find your efficiency problems, and the risk of a stuck mash is not worth it.

 

[Gustatorian]

I do not believe a double crush is worth messing with on this system... Generally the crush is about the last place you'll find your efficiency problems, and the risk of a stuck mash is not worth it.

Really? I've had several friends up their efficiency on 3-vessel systems by increasing crush. I know it will at least give me 2-3% more, but I don't know if I should risk it...

 

[Gustatorian]

anybody know if pH will drop due to scorching the boilcoil/wort? I'm usually spot-on with calculating pH and the batch I brewed today was 0.2 points below. I did have some issue with keeping the boilcoil submerged, but everything else checks out. Scale is measuring perfect, grain bill check out in EZ water calculator and BruNwater. Anybody have any theories...?

 

[scullerkurt]

Not sure about scorching impact on ph, but I wonder about water ph, and grain ph (they aren't fixed values)

 

[jackers252]

Here is a dumb question. How do you guys do your sparge at the end? Do you ramp the temp up to 170 and as soon as the tower reads that, start your 10 minute timer, or do you wait for your grain bed to reach 170 before starting the timer?

I've been starting it once the wort temp hits 170 but I'm wondering if I'm missing some sugars that way.