1 Posted: Friday, December 23, 2016 8:41 AM

Hi all,

I'm fairly new to brewing. For my 6th batch I thought I'd give a lager a bash. I have a kegerator set up and a spare fridge. I'm doing ESB's Czech Pilsner using 2 x 11.5g of saflager s23 for 22 litres. Although I have a spare fridge I have no temp control. On the ‘warmest’ setting the fridge gets the wort to about 8c. The ideal temp for saflager is 11-15c.

My question is…do I need to be concerned about the low temp?

My solution is to fix a timer to the fridge - off for 3 hours; on for 3 hours over a 24 hr period. Is this okay? Or is it worse than leaving the brew at 8c?

All help greatly received for this novice brewer (who's no longer a lurker :)


2 Posted: Friday, December 23, 2016 9:36 AM

Welcome to the forum!

As a first time poster, it would be nice if you were making a Coopers brew but anyway…

A timer can work quite nicely. This is what I used before finally buying a temp controller.

Assuming you have the radial type with little segments to push in for on or off - consistent temp can be managed by running for a short time every hour or so (eg 15mins every two hours). It just might take a little bit of fiddling about to get the suitable duty cycle for your situation.

3 Posted: Friday, December 23, 2016 10:03 AM

I'll do a Coopers next time I promise

So you reckon short bursts of cool will work better than my 3 hours on, 3 hours off. I'll do as you say and do either 15 or 30 mins every 2 hours.

What I love about brewing is it's all just one big experiment and a bit of trial and error. But this forums has taught me lots on my steep learning curve into beer making!

4 Posted: Friday, December 23, 2016 10:56 AM

Short bursts definitely would work better. I have a temp controller on my fridge for fermentation and it probably comes on maybe 3 or 4 times an hour for I dunno..5 minutes at a time, to keep the temp where I want it. If you left it on for three hours it would drop the temp too far, although being a lager yeast it'd probably keep fermenting anyway.

What you want to avoid also is large temperature swings that would occur from leaving the fridge on for 3 hours and then off for 3 hours. Stable temperatures are the best for fermentation. Equal times on and off doesn't really achieve this, you only need short bursts every so often to keep the temperature stable at fermentation temps. Assuming you're measuring the temp of the brew and not the ambient, it will probably take a bit of fiddling with the settings to get it to stay around 11C or wherever you're fermenting it. But something like what PB2 mentioned would be a good starting point.

5 Posted: Friday, December 23, 2016 11:07 AM

Thanks for that - makes sense.

I've set the timer to do 30mins every 2 hours for the 24 hour period. I'll start there and drop to 15 mins every 2 hours if I need to. Yes, I was taking the wort temp - 8-9c…which is too low.

Cheers guys,

6 Posted: Friday, December 23, 2016 11:12 AM

That yeast can go as low as 9C but yeah, better around 11-12 I'd imagine. You might get a more consistent temperature by setting it to come on for 5 or 6 minutes every half an hour - this prevents it from getting the chance to warm up too much.

7 Posted: Saturday, December 24, 2016 2:14 PM

Just an update: I set the timer to come on for 15 mins every 2 hours over a 24 hour period. The temp has settled between 12-13 degrees and the brew was bubbling away nicely when I check it this morning. Success! Thanks again.

8 Posted: Tuesday, December 27, 2016 8:11 AM

Hi again,

My fermentation is about to start slowing down on the Czech Pils. Couple of questions…

1) Do I need to do a diacetyl rest? If so what temp (room temp?) and for how long?

2) Also I was thinking of adding a small amount of finishing hops - Saaz (12g as a tea/steep). For a lager when should I do this and again, for how long?


9 Posted: Tuesday, December 27, 2016 9:29 AM

FM - here is a link to an Inkbird pre-wired temp controller. I'm using one of these and also a STC1000 which requires wiring. The Inkbird is an easy way to go for a few dollars more, just plug and play. I'm running the STC1000 on my FV fridge and using the Inkbird on my keg fridge as the keg fridge thermostat is kaput.


10 Posted: Tuesday, December 27, 2016 9:52 AM

Yeah it'd be far easier with a temp controller like Morrie has mentioned. I also run one on my fridge; it's pretty much set and forget. During fermentation it probably comes on about 3-4 times an hour for a few minutes at a time.

As for a D-rest, I normally do mine at about 18C and leave it up there for a few days after it reaches FG. After this, the beer is chilled down to 0C for a couple of weeks before being kegged and bottled. If you're bottling you can get away without one as it'll happen in the bottles anyway, although raising the temp in the FV will probably see it finish fermenting a bit sooner.

If you're doing a hop tea you can add it at bottling time. Depending on your bottling regime you can either add it directly to the FV and give it a very gentle stir, or if you bulk prime you can add it to the empty bottling bucket along with the priming sugar solution and then transfer the beer onto it to mix it in.

11 Posted: Tuesday, December 27, 2016 4 PM

Thanks guys.

My plan was this…Like you said Otto, I was gonna D-rest once i'd got FG. At that point, I was gonna do my Saaz tea (which is just one of those easy tea bags that you just brew in a cup for 15 mins) and then drop the whole thing (bag and all) into the fermenter at the beginning of the d-rest. After 48 hours I was gonna bring the temp down to around 10c for 48 hours more. Then remove the Saaz bag and lager in the fermenter for around 7-10 days before kegging and putting in the kegerator…and leave it untouched for another couple of weeks before serving. (Q - sound I move into a 2nd fermenter before lagering it for 7-10 days?)

Does that sound like a reasonable plan overall?

And yes, def gonna buy some kind of temp control as I'm a big fan of lagers and would like to mess around with many more.


12 Posted: Wednesday, December 28, 2016 10:58 PM

I normally raise mine up to 18C when the SG drops to about 1.020 or a tad higher. It then stays up there for about 3-4 days after FG is reached. After this it's dropped to 0C for two weeks before being kegged/bottled.

If you are going to lager it you might as well do it properly, i.e. at 0C or as close as possible. 10C isn't really lagering temp. No need to move the beer to another FV for this period though, it's not really long enough to cause any issues with it by being left in the primary. If you were lagering it for 2-3 months then yes, you would be best moving it to another FV.

Saaz has a bit of a tendency to leave grassy tones in the finished beer if it's left in there too long. With a hop tea though, it probably won't do this. Even so, once the hops have been steeped in the hot water, they won't really be of much use to the beer, so you'd be better off simply tipping the liquid in and disposing of the hops.



13 Posted: Saturday, January 07, 2017 10:42 PM

I use an external thermostatic switch to accurately control temperature. Much easier than making alterations to an existing fridge and I'm sure every bit as accurate. It has a probe which sits in a bottle of sanitizer solution in the fridge (not in the brew itself as a hole in the fermenter lid invites infections). In warm weather in most parts of Australia you only need one to turn the fridge power on and off at the desired temp, but in winter you may need heating as well, depending on your climate and the desired brewing temperature. This can be achieved using a second thermostat unit attached to a heating cord of the type used to heat reptile tanks. The thermostat units can be set either to switch on at above or below a set temperature.

The thermostat units cost about $15 each from memory and the reptile cord likewise (from Ebay of course). If you have purchased a fridge (or multiple fridges perhaps, for lagering?) you really should consider going all the way with temperature control.

14 Posted: Sunday, January 08, 2017 6:57 PM

Must say, I'm very interested in the ExBeeriments done on lager fermentation temps. If anyone hasn't read the tests there's a few of them, one going as far as brewing one at 10 degrees with the other way past Fermentis' recommendation of 22 at 28 degrees. The difference was basically negligible and un noticeable by a host of judges in blind tests

I'm no massive expert personally but the lager and pilsner kits I've experimented with different yeasts and temps yield no noticeable results either. Fact if anything, I preferred the ale temp fermented brews more. I chalk thus up as 1x 7g pack of yeast is not ideal for lager temps (or so I read and calculators tell me) these weren't side-by-side tests as such but I really noticed very little difference

We've got to remember that lagering originally came into force when brewers didn't even know what yeast was. It was a complete mystery. From what I understand lagering was a good way to keep infections to a minimum, even though these were known to be just bad tastes at the time remembering we hadn't discovered yeast yet. The German Reinsgebot (or however it's spelt) law was once: Malt, hops and water. It needed to be legally changed later in to include a another ingredient: yeast

15 Posted: Sunday, January 08, 2017 7:10 PM

Better off taping the probe to the side of the fermenter underneath some foam than sticking it in a jar of sanitiser or whatever. The jar will change temp quicker than the brew will, so the accuracy is unknown really.

What occurred centuries ago is largely irrelevant now because of the knowledge we have. I did a couple of lager kits at ambient in winter with one pack of kit yeast and they were shit. The ones I've done since, with proper pitching rates and cold fermentations have been much better. There's a reason these pitching rates and temperatures are recommended - they work.

16 Posted: Sunday, January 08, 2017 7:12 PM

I think it really depends on the yeast to be honest. I have done W34/70 at 10c and another which was ~ 13c and the difference was bugger all. S-23 i have done at 10c and at 13c and the 13c didnt even taste at all like a lager. More like a fruit ale.

Anyway best results I have got have been keeping lagers in the low temp range of the yeast.

17 Posted: Sunday, January 08, 2017 8:42 PM

I'll just have to try it for myself. But the experiments with so many judges couldn't be skewed, I wouldn't think. I for one preferred or was at least completely fine with the 18.5 degree kits I did anyway. Both are always equally as bad as each other

18 Posted: Monday, January 09, 2017 12:21 PM

I'd suggest that a lager fermented low with not enough yeast wouldn't be all that great, though. There are other factors besides the temperature at play.

I think the Brulosophy experiments on this kind of thing would hold a little more weight if they did it with all the yeast strains instead of just one or two. Even then, it wouldn't sway me in to fermenting lagers warm. They should also do one where one batch is temp controlled and the other allowed to fluctuate all over the place.*

It should be noted that cat pee like VB, Carlton, Tooheys etc. are all fermented warmer than traditional lagers. Perhaps this is part of the reason they all taste like crap.

*If they have, I'm unaware of it at this point.

Last edited by Otto Von Blotto (Monday, January 09, 2017 12:21 PM)