Importance of constant temperature and it being air tight?!

[ToyCar]

Hi guys,

New here so forgive me for asking such simple questions!

I'm brewing a Coopers Green Neck lager, and it's in my conservatory. I've got a big black bin half full of water which I've put my home brew barrel inside. I've got an aquatic heater thing in the black bin to keep the "dirty" water warm, so then keep the brew warm

As it's in the conservatory, it gets cold at night and warm in the day (it's actually sunny in the UK!!!) So I've wrapped it in an old duvet and put a towel over the top. And during the day I put an umbrella over the top of that to try and keep the temperature constant.

The heater is set to 18 degrees c, the lowest it will go. But during it day it goes up to about 20 degrees, and at night I reckon it goes down to about 16-17 degrees c. Is this a massive problem? Will it ruin my beer?

Second question, I've left the lid lying on top, as in, if I pushed it down then it would seal it air tight. I did this to start but it got really pressured and had to keep opening it to let the pressure out. Will leaving it not on fully let germs and stuff in and ruin my beer?

Sorry for such a long post!!

Would really appreciate any advice :)

 

[PD]

try and get it to hold at 18-20 degrees constant if you can certainly no higher than 23. going low is not so bad the yeasts just fall asleep.
Air tight is unachievable and unwanted, just keep the brew covered by a loose lid. When fermentation has slowed down fix the lid on all way round......and no peeping for 10 days.

 

[joe1002]

As PD says its best kept at a constant temp, the yeasties don't like temperature fluctuations, particularly in the first 3-4 days. I doubt I would go to 16c with your heater system, remember the ambient room temp won't be the temp of your beer :thumb:

 

[calumscott]

Sounds like you should be fine.

As PD says cool and constant is best. Kits around 18C if you can. Conservatories aren't the best places to brew because of the massive temperature fluctuations. Do you have a "steadier" place you could ferment? I like the idea of the big dustbin as a heat sink though...

Airtight is bad unless you're a big-boy with pressure vessels and the like, that's how the likes of BrewDog do it but even then it's not airtight, it's pressure controlled.

The best you can do is airlocked, so completely airtight with an airlock to let the fermentation by product CO2 out but you need good fermenters like these or these to achieve that. The normal ones really don't seal that well anyway so there's little point...

 

[rpt]

I clip the lid on my FV and the CO2 still finds a way out - the lid bulges a little. Traditionally fermentation has been done in open vessels so I wouldn't worry about infection.

 

[ToyCar]

Great, cheers for the advice! :thumb:

I peaked about 4-5 times before I read "piddledribble"s advice, does this mean that it's likely to have gotten infected?

I've got a shed, would the temperature fluctuations not be so bad in there?

 

[rpt]

I wouldn't worry about peaking. It's difficult to avoid when you first start out.

I think a shed would have worse temperature fluctuations as it will probably get much colder at night, and, except in summer, is likely to be a bit cold.

 

[calumscott]

I peaked about 4-5 times before I read "piddledribble"s advice, does this mean that it's likely to have gotten infected?

Unlikely. Don't worry.

I've got a shed, would the temperature fluctuations not be so bad in there?

You'll have even less control there. Don't you have a little corner of the house somewhere that you can tuck it away? Just a little place, out of the way, where the missus/cat/dog/children won't bother about it?

 

[ToyCar]

Sadly not, very small house

Massive achievement to even get it in the conservatory :?

 

[anthonyUK]

I've got a shed, would the temperature fluctuations not be so bad in there?

I have my fermenting fridges in the shed.
You can see the temperature swings in green and the more stable liquid in blue. Both of these are measure INSIDE the fridge so the fluctuations will be greater still.