defenestrate

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so far all of my AG (5 all together) have been in the neighborhood of 75-80% efficiency. i recently picked up a second cooler and a pump, and have been having some heat problems.
two brews ago, i was unable to keep my sparge water hot enought to bring the mash up to the upper 160's (highest i attained was 162). i still ended up with 76%.
my last brew, a belgian blonde, turned out pretty poorly. i had the same problem with sparge temps. in my HLT the temp was holding at 185, but between the HLT and the mash tun it was dropping considerable heat, only reaching 160 once stirred into the grains. my target OG was 1.05 and i hit 1.033. ouch.
now to be fair, it has been roughly 35 degrees outside both times, and i think thats attributing to the heat loss (pumping through the hoses with such cold air) but also not having it hot enough in the HLT. i'm thinking 195 next time.
i also used 4 lbs of wheat malt in the belgian which i've never used before, would this make higher effeciency harder?
last but not least, i also used tap water. every other time i've brewed i've either used brita filtered water or spring water. i'm thinking its probably poor pH in the tap that hurt?

any ideas? thanks for reading

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RCCOLA

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The names of your brews are disturbing at the very least.I would never say I'd had a rusty trombone in my mouth.

maltMonkey

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Not an answer, but just some thoughts:

-- I always have a tough time keeping my mash over 160° during the fly-sparge as well, but I've never noticed it hurting my efficiency. I usually have to heat my sparge water to about 190° to keep everything in range.

-- A light grain bill (no dark malts) will have a higher mash pH than one with a darker grain bill. I don't know what you normally brew, but I noticed you've brewed a stout and an amber.....if your other beers have been darker, that might be why your efficiency took such a hit on this lighter bill. You might have ended up with a pH way higher than 5.7 on this one, and should probably start checking the mash pH and adding water salts or 5.2 buffer.

-- I always get a bit lower efficiency when a large portion of the grist is wheat.

-- You mentioned how cold it has been outside. How are your mash temps? If they are dipping too low you might not be getting full conversion. You might want to check for conversion with iodine, or extend the mash to 90 minutes or so.

-- Are you fly sparging? If so you might want to try this: after you've run off everything to your boil kettle, take a sample of your final runnings. Then stir the mash up and let it settle back down for a few minutes. Take another sample of these runnings and compare. I did this recently and discovered that my final runnings were about 1.011, but after stirring it was pouring off 1.021. It helped me figure out that my sparge manifold is sitting too high and a lot of the sugars are getting trapped underneath.

david_42

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I'd say low sparging temperature is the problem. Try some pipe insulation on the hoses, if that is possible with your setup.

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cmgray

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If you're truly worried about ph, you can either get some test strips and see, or get some 5.2 buffer and put that in your mash. Then you know your pH will be right on and you can see if that's the difference.

Personally though, I don't see anything wrong with 75% efficiency.

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Denny

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Often times wheat won't crush as thoroughly because of the smaller kernel size. If you don't compensate for that, it could reduce your efficiency.

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hopsalot

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agreed, 75% is sufficient

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maltMonkey

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I think he was saying he was getting 75% efficiency (which was acceptable) until he used tap water this time and missed his OG by 17 points.

cmgray

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Ahh sorry. I misread the OP.

In that case, unless it becomes a trend, I'd say you're fine. If it was an anomoly and your process hasn't changed. Then it was probably a crush problem, or maybe incomplete conversion. Did you do an iodine test?

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Yankeehillbrewer

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I don't use wheat myself, but have read that a handfull of rice hulls can help with lautering and could thus increase your efficiency.