Chiller - Too Cold? (Beer Temp Drop)

[brewingnewbie]

noticed that the other day that my fermenters dropped a few degrees each the other day.
one is a lager is set at 50, the other an ale at 67
a cold front had hit on the weekend so the rooftop chiller was probably around 40-50 degrees at night.
the brewery was 65, usually its more towards 70-72.

noticed the lager was down to 65 and the lager was at 46!
i figured it was the ambient temps affecting things. heated up some water and raised the room temp to 80, shut off the glycol to try and raise the beer but i must have not tried long enough.

went up on the roof tonight. the piping out of the reservoir to a pump then to the condensor was iced up. temp gage on pipe read 37.the hvac guy set the controller was set at 24 +/-5 which i figure is too low. i set it at 33 +/- 3 and at least the icing melted and the gage went up to 41.

think the low setting and the change in ambient temps just are too low?
i need to raise the temp in a couple of days for a D rest and need to figure this out.

brewery is now at 70 tonight and i'll have to see what happens tommorrow morning. might have incorporate a heater in the room.

any thoughts?

[hopsick]

i brewed at a place wher that was a factor .what we came up with is a small space heater under the tank with grain bags stacked around like sand bags that worked as well as hot water bath for the tank . also you could put the beer into the fermenter 3-or 4 deg higher and leaving the glycol off until the next day or so . we have also cerculated a clean tank with really hot water and then transferd the beer into it..That got the yeast kickin again..good luck yo

[gitchegumee]

Weather should not be a factor with your tank temperatures. It may make the chiller work less, but it should not decrease your tank temperatures. Your solenoids turn on & off the flow of coolant to your tanks. If the coolant is at a constant temperature, then something else is going on. Most small breweries I've been to have fermenters with a tendency to dip below the setpoint. This is due to the temperature sensor turning off the solenoid when the beer temperature drops past its setpoint. Check your deadband or "offset" on the controller. It should be set to 1, or at most 2F. When the solenoid is switched off, the convective cycle inside the tank and the icy cold coolant still retained in the jacket combine to lower temperatures past the setpoint. This is exacerbated by really cold coolant temperatures. In any case, unless you're really worried about a few hours at a slightly different temperature, it may not warrant much fuss. I know that it doesn't bother me much because the phenomenon is repeatable on every batch and my beer is consistent. Hope this helps! Good luck!

[brewingnewbie]

it's just kinda of a odd happening. never had it happen before.

i am going to put a heater in the brewery tomorrow and try to heat up the fermenters to their proper temps.

the problem i am running into is that the ale is due to its 3 degree temp diacetyl raise. we'll see what happens.

[Gregg]

Plenty of ideas for warming fermenters

Warming fermenters has been discussed recently; I searched for "warm glycol" - here is one thread.

Gregg

[brewingnewbie]

found out that i misread the gravity of my ale. fermentation was coming to a halt and producing less heat coupled with the fact the temperature of the building dropped the night and it lowered the beer too much. i missed the diacetly raise on the ale but i tested it by heating up a sample and didnt detect any...also its 1056 yeast which is pretty clean.
the lager only dropped a few degrees which is fine for it.

ended up shutting off the compressor of the glycol unit, heating up some water in the kettle to 130F, circulating through the heat exchanger with the heat ex. glycol lines on. it heated up the glycol then i circulated through the 2 tanks. got my lager up 5F so i could get a rest on that. put a heater in the room until time to crash.

thanks for all the input! always seem to learn something helpful

[gabewilson50]

the lager only dropped a few degrees which is fine for it.

I'd be more concerned about your lager drop in temperature than the ale. The ale truly was just a few degree drop (68 deg being a very common fermentation temp), but your lager dropped down to below 8 degrees Celsius (sorry, but my experience with lagers is in a SI unit country), which is quite cold for a primary fermentation. That's at least 5 degrees F colder than some of the colder ranges of lager primary fermentation (at least from what I've been able to determine). Just keep an eye on your gravity, the real key will be if it pretty much slowed down to a stop or not (then you're basically lagering and would need to revitalize your yeast).

Good luck

[dick murton]

Are your FVs insulated ? A serious question as I worked at one place where the open FVs were not lagged, and we used to suffer in witer if someone left the door open, or in summer, when the cooling couldn't cope. THis affected temperature, fermentation speed, final pH and beer flavour - so it can be a serious issue.

Other possible explanations not talked about so far include sticking coolant control valves, or damaged seals

Cheers