Help! Consistent low FG

[epicac2]

My efficiency has recently jumped and the last 6 or so brews have come out with a higher OG. Lately I've been getting about 80% efficiency. Im normally shooting for OG around 1.056 and most end around 1.070. Not only that but my FG always ends low. Between 1.004-1.008. Any idea why this happens? I calibrated my thermometers yesterday(boiling/ice water method) and discovered they were a couple degrees off. Could this be the culprit?

I brewed a Brown ale 14 days ago and just checked the gravity and its currently at 1.009. Im afraid it will drop a few more points in the next day or so. Should I just keg it now?

Here are the stats on the Brown Ale..

US 2-Row Malt 10.00 lb 87.2 %
US Caramel 90L Malt 0.50 lb 4.4 %
US Caramel 60L Malt 0.50 lb 4.4 %
US Chocolate Malt 0.41 lb 3.6 %
US Black Malt 0.06 lb 0.5 %

Water to grain ratio is .32 gallons per LB of grain(1.28qts/gallon)
Mashed at 154 for 60 minutes

Pre boil -1.048(target 1.048)
OG -1.067(target 1.061)
FG -1.009(target 1.015)

Wyeast 1056 American Ale

According to my software, my yeast attenuation was 86.3% !!!!!

I make 1 liter starters(100g DME) and use a stir plate. I ferment for 24-48 hours then cold crash for about 36 hours, decant and pitch.

My hydrometer has been calibrated with 60F distilled water

 

[Bradinator]

Were the thermometers higher or lower? If they were reading higher then they should have been it could be the culprit as your mash temp would actually be lower.

I would also check your hydrometers calibration as it should be 1.000 in water at a specific temperature. Most are calibrated to 60F as far as I know, but I could I believe some can be different.

Also make sure to remember the temperature of the wort will effect the gravity reading taken. Beersmith has a 'hydrometer adjust' tool just for that.

Those are the only reasons I can think of, but maybe someone more experienced can chime in too.

 

[epicac2]

Were the thermometers higher or lower? If they were reading higher then they should have been it could be the culprit as your mash temp would actually be lower.

I would also check your hydrometers calibration as it should be 1.000 in water at a specific temperature. Most are calibrated to 60F as far as I know, but I could I believe some can be different.

Also make sure to remember the temperature of the wort will effect the gravity reading taken. Beersmith has a 'hydrometer adjust' tool just for that.

Those are the only reasons I can think of, but maybe someone more experienced can chime in too.

Yes my therm was reading higher. meaning my actual mash temp was 152, instead of my intended 154. My hydrometer was calibrated at 60F in distilled water. Yes I use Beer alchemy and it does adjust for temp. I take a temp reading every time I check gravity