Problem with high final gravity

Hi everyone,
I'm pretty new to all-grain brewing, and have a consistent problem with having high final gravities. I assume that this is related to the fact that I'm also having a very difficult time hitting my target mash temps, but an iodine test has been showing conversion, although maybe i'm doing that wrong. I keep ending up with a FG between 1.020 and 1.028. The beers aren't bad, but they're not what they're supposed to be. My mash tun is a 10gal round cooler and I just got a false bottom. I'm close on mytarget SG, so I think my efficiency is ok, I'm just having trouble with conversion. Here's an example of my most recent brew day:

Grains:
11# US 2 row
1# Crystal 40
2# Vienna
.25# Carapils

1. Preheated Mash Tun with 6 gal of 158 degree water for 90 minutes
2. put grains into Mash Tun
3. Added 4 gallons of 168 degree water
a. Measured temp at 149
4. Added 3Q boiling water (took almost 20 minutes to boil the water)
a. Measured temp at 156
5. Added 2Q boiling water after 45 minutes
6. Iodine test after 70 minutes showed conversion.
a. To do the iodine test, I'm just taking an eye dropper off the top, is that the best way to do that, or am I missing something there?
7. Sparged with 3gal of 180 degree water
8. boiled down to 6 gal
9. SG measured at 1.060

I took a gravity reading after 4 days because the airlock had stopped bubbling and it read 1.026. I just took another reading today which is 2 days later, and it still reads 1.026. The yeast was Wyeast 1056.

This is basically the exact same thing that happened with the last batch with the same recipe, and it's been very similar results (although sometimes much worse) the previous 2 batches. I don't know if this is just learning pains as I get the process down, or if I'm doing something wrong. Any help/advice would be really appreciated.

Cheers

 

What was your target mash temp? What kind of beer are you making?

All those boiling water additions are probably getting you too high. If you are making a beer you want dry, like a California style IPA, 149 is not a bad place to be. Especially with all that crystal malt. Might be a good idea to just let a batch run at whatever temp you end up at and see how it turns out.

My guess is you are trying to hit too high of mash temp.

What are your oxygenation procedures? That would be another likely culprit in your yeast stalling out.

 

i was targeting 154, and it's an IPA with no regional preference.

Ok, so if I'm going for a lower temp mash, like 149, any advice on how long I should expect the mash to mash for?

as for oxygenation, I do a lot of stirring but that's about it, and once it's in the carboy I just let it be. Think it's worth jostling the carboy around a bit to try to get things going for a little longer?

 

oh... also - thanks for the reply

 

First- how are you measuring SG ?
Second- if your target was 154° & you were at 156° after your first boiling water addition, WHY did you add more boiling water 45 minutes later? What was the temp then?
Honestly, you would have been better off leaving it alone at 148°. You'd have had more fermentables and a drier IPA.

 

I measured SG with a refractometer, and I added more boiling water because the temp had dropped to 145.

 

you should check your SG with a hydrometer.
refractometers aren't accurate once alcohol is present.

 

Umm, am I wrong to think that there's no alcohol until yeast has been added?

 

Actually, I see that my acronyms are wrong. i thought SG was starting gravity. I was measuring both OG and FG with a refractometer, but I just took another reading with a hydrometer and got 1.012. Ok, so, turns out everything's good. Thanks.

 

A mash takes as long as it takes. Checking for conversion is a good process. I mash for 60 minutes on all my batches. That gives me a more consistent baseline. That said, most of the conversion will happen early. That is why you don't need to sweat the temp quite so much.

Once fermentation has begun, refractometers have a error. There are some conversion charts you can use. Not sure how accurate that system is though. Hydrometer is the way to go.

As for oxygenation, you might try a vigorous shake for 2 minutes. A little stirring might be enough, but for any big beer you want to try to get as close to saturation as you can.

Hope the beer turns out great! Let us know what you think when it's done.