Cooler temps that fluctuate while fermenting?

Im about to brew my first beer, I just purchased my delux starter kit and i choose Irish Red Ale. My major concern is were to ferment. I live in PA, it would be rare that the temps will get warmer than 65 degress nights go into the 40s and mid 30s. when i am in my secondary fermentation nights can go into the 20s. Now my question is how cold can my fermenter get and can the temps fluctuate. I would keep it in a dark room that could range from 60 degrees during the day and go down to 45 degress at night. The reason that the heat is not regulated is because I am not always at the house. Can the temp fluctuate from night and day, it will be very unlikely the temp would go above 70 degress?? Will this affect my fermentation of my Irish Red Ale?? Any advice or tips will be greatly appreciated.
Thanks, Dave

Once fermentation is rolling the internal temp of your fermentor will exceed ambient by a few degrees (say 2-6) depending on available sugars, vigor, yeast strain, etc. You didn’t specify what yeast you pitched or the quantity and health. These will all effect your outcomes, but it’s likely you’re using an ale strain. Most will not tolerate the temperature swings you indicated well.

You’re going to need to find a way to insulate your fermentor to ensure decent beer. There areva lot of ways you can achieve this. One simple way is to simply dump your fermentor into a cooler filled with warm water, add reheated water as neccessary. Most other means are better ala more stable.

Edit: you haven’t brewed yet. Good! In addition to the temp control you might want to look into using lager yeast.

Going from 60F to 45F overnight will drop the yeast and stop fermentation. Cheap and easy solution is a swamp cooler setup, which can do second duty as a swamp warmer, just add an aquarium heater to the rig. Basically it’s a big tub of water that acts as a heat sink for the fermenter, or in this case as a warmer, and it stabilizes the fermentation temp since the volume of water in the tub exceeds the volume in the fermenter.

Im using a dry Ale yeast and making five gallons, Thanks for the advice!

Surely your temperature doesn’t vary that widely indoors? If at all possible you need to find a location with more temperature stability. Some fluctuations are fine (the beer has a large thermal mass and will vary more slowly than its environment), but the swings you’re describing are just too much. So yeah, if that’s the environment you’re going to be in, you’re going to have to invest in some means of temperature control.

I ferment in a closet in the winter time and use a small $10 ceramic space heater to keep temps up. It has a safety on the bottom so if it falls over, it will turn off.

Thanks for the tips everyone. i really want to brew this weekend but im really not sure where to ferment, im hoping i dont have to do it at a relatives house. I was thinking about the swamp cooler that was suggested by shadetree. Now if i were to get a storage container and fill it with water and put the carboy in that with temperatures still fluctuating from day and night will my swamp cooler fluctuate much? the reason the house will fluctuate is because i am going away for a week in November and i always don’t spend the night at the house so the heat is usually turned down low. Do i have to get a aquarium heater or is that not necessary. maybe i can set the heat in the house at fifty and put the swamp cooler near the thermostat and then cover it so it keeps dark.
Thanks Dave

If you are brewing this weekend, the beer will be done fermenting well before you leave. In 10-14 days. temp swings after that are not a big issue.

Your beer will be fine to leave in the primary fermenter until you get home to bottle it. Setting in in a tub a water will help with keeping the temp stable while you are ways.

Set your thermostat to 55-60*. Unless the temps get into the upper 80’s outside, I doubt the house will warm that much.

Do you have a basement? The temp swings are much less there than on the main floor.