How warm is too warm for the ambient temperature for the primary fermenter? I’m using Safale US-05 yeast. The ambient temperature reads 77 (F).
The act of fermentation creates heat within the wort. Upwards of 10 degrees or more. Safale says the ideal fermentation temperature for US-05 is 64 to 82 degrees F. So if my ambient was 77 I would find a way to bring the temperature of your fermenter down. Something like a swamp cooler is probably the simplest and least expensive option.
That’s too warm…way too warm. You want beer temp to be in low-mid 60s ideally, so the ambient would need to be 5-10F cooler.
Thanks, Denny and Kevin. I’ve been keeping a towel, saturated with water, wrapped around the primary with a small box fan blowing on it. I’ve added water to the towel about three times a day to keep it wet and the temp has dropped to between 67 and 70. That’s still not where I’d like it to be. Since I only have a crawlspace to store my beer in during fermentation, I’m guessing that I’ll need to confine my brewing to three seasons out of the year–i.e., not in the summer.
Consider making a simple box out of foam insulation and using frozen water bottles for cooling. You can achieve cooler temperatures pretty easily just by swapping out the frozen bottles.
I’ve been thinking about this type of setup A LOT in the past few weeks. Maybe a “swamp cooler” setup using an igloo cooler to put ice in. It would be super swell to have an output hose blowing swamp cooled air into an insulated box.
I’m using a wet shirt over my bucket right now with a fan blowing on it. It does keep temps lower than ambient, but that’s only until the shirt dries out. It needs constant attention. Still better than nothing, but it’s begging for improvement.
UPDATE: Added a 30GPH aquarium pump and a couple feet of 1/4" poly tubing to keep the shirt wet 
What a great idea! An insulated box, large enough for my 6.5 gallon primary, with enough room for some frozen water bottles. I’ll explore that construction project and, hopefully, with this new resource I’ll be able to continue to brew in the summer. “Why not brew some,” indeed!
A bathtub that won’t be used for a couple weeks always works. The water absorbs a lot of the heat and adding ice or frozen water bottles to bring the temp down will stabilize the beer temp
I did something like that for years, although using a large plastic muck bucket in a closet rather than a bath tub. Works really well.
I still do the swamp cooler thing from time to time for ales in the summer when my basement is running hot. My fermentation keg fits neatly inside a 6.5 gallon brew bucket It’s enough to keep the temperature from spiking during peak fermentation, then I pull the fermenter out to let the beer finish after 3 or 4 days.
I appreciate all these great ideas. Looks like the simplest option would probably be a large plastic trash can filled with ice/ice water. But I’m also considering building a simple, insulated box (30" tall and 19" wide), with 1" polystyrene foam boards with foil backing. I thought I’d make a lid out of the same and then glue some bead board onto the foam board for the base (the bead board is to keep the fermenter bucket from denting into the insulation). If I place four 2-liter plastic pop filled with frozen water in the corners of the box I’m hoping it will keep the temp in the low to mid 60s even when my crawlspace is in the mid to high 70s. What do you think?
Four frozen bottles will very likely get you to lager fermentation temperature. Cheers!
Okay, thanks. I’ll check the temperature for my ales frequently until I get this thing figured-out. With a primitive “ice box,” like I’m building I guess I can adjust the temperature by removing frozen pop bottles as needed. But I hope you’re right. I’d like to try brewing some lagers sometime!
you can also look into yeasts that perform better at higher temps
Agreed, selecting a yeast for the environment,
is easier than changing the environment for the yeast.
Assuming you like the character of the yeast. Most times I prefer to change the environment rather than accept a compromise
And that’s if a yeast is available for your environment at the time. I find the environment much “easier to control” than finding a yeast that will produce the beer I want in some of the environments I would otherwise experience in my home location through the course of a year.
Never tried high temp yeasts.
Tried them and most are not to my liking for the most part. But I brew lagers and British ales mostly.
Thanks for the suggestion about adjusting the yeast to the environment. I’m still relatively new at brewing. What are some good (and hopefully not too expensive) yeasts that perform well with ambient temperatures in the mid to upper 70s?