Brew fridge cooling rates

[afromaiko]

I just want to run this by others here that are fermenting in a fridge or freezer...

I'm about to brew a lager, so am giving my recently acquired brew fridge a dry run to check if it's capable. It's a fan forced model with the freezer on the bottom and using a Fridgemate thermostat.

I filled a fermenter with about 20 litres of water and put it into the fridge compartment. It took about 24 hours to drop from the initial ~20C down to 10C - which I'm planning to do for primary fermentation.

I've left it run for 48 hours now and it's dropped it to 3C but doesn't seem to be dropping much more. Is 3C going to be fine for lagering?

The fridge has been cranking away on full the entire time to get the temperature down this much. The fan forced model seems kind of inefficient, not much airflow really gets blown up into the fridge section. The freezer is plenty cool enough though.

I have thought about perhaps using the freezer section for lagering instead, but worried that it might be too powerful and end up freezing my beer. However, I can fit a 20L cube in.

How do the cooling rates above compare to other people's experiences?

thanks
Afromaiko

[lethaldog]

I just want to run this by others here that are fermenting in a fridge or freezer...

I'm about to brew a lager, so am giving my recently acquired brew fridge a dry run to check if it's capable. It's a fan forced model with the freezer on the bottom and using a Fridgemate thermostat.

I filled a fermenter with about 20 litres of water and put it into the fridge compartment. It took about 24 hours to drop from the initial ~20C down to 10C - which I'm planning to do for primary fermentation.

I've left it run for 48 hours now and it's dropped it to 3C but doesn't seem to be dropping much more. Is 3C going to be fine for lagering?

The fridge has been cranking away on full the entire time to get the temperature down this much. The fan forced model seems kind of inefficient, not much airflow really gets blown up into the fridge section. The freezer is plenty cool enough though.

I have thought about perhaps using the freezer section for lagering instead, but worried that it might be too powerful and end up freezing my beer. However, I can fit a 20L cube in.

How do the cooling rates above compare to other people's experiences?

thanks
Afromaiko

You want to brew it at 9-10*C, for lagering the best is between 1-2*C but 3 would still be fine and you would probably find it would drop to 1*C over a couple of days anyway, i have an old kelvinator and it has no trouble getting down to 1*C

[afromaiko]

Thanks, I will leave in another couple of days and see how much more it drops. Hopefully it will stabilize a bit and the fridge can have a rest. Was just wondering if it was struggling a bit.

I opened the door once to check and there wasn't really any noticeable cold air blast that came out although the thermostat is showing low temperatures. But the interior walls don't seem that cold either. I might consider adding an additional fan to help suck the air up from the freezer when the fridge cooling cycles are running.

[mikey]

That type of fridge will use more power than a freezer on type style because it apparently takes more energy to get the freezer temperature down.That might be why it seems to be working harder.

[geoffclifton]

I think you'll find that the frost free function will interupt your attempts to get much under 3 deg. A fridge is designed to keep food at 4 deg. I have a FF house fridge and agree you don't get to feel that cold blanket of air like in an evaporator plate fridge.

IMHO a FF is way better than no fridge, evaporator (ie cyclic defrost) better and a single door fridge OR freezer with a fridgemate the best. Don't forget a chest freezer will also do a great job.

BTW I hope your lagering is worthwhile and tastes a hell of a lot better than the Coopers Lager I did on half dex half ldme. OK I know it's an ale yeast but if the target flavour was correct then it's just thin, pale and slightly sour. No such problem with their draught, bitter, Canadian blonde and stout.

Cheers, Geoff.

[lethaldog]

I think you'll find that the frost free function will interupt your attempts to get much under 3 deg. A fridge is designed to keep food at 4 deg. I have a FF house fridge and agree you don't get to feel that cold blanket of air like in an evaporator plate fridge.

IMHO a FF is way better than no fridge, evaporator (ie cyclic defrost) better and a single door fridge OR freezer with a fridgemate the best. Don't forget a chest freezer will also do a great job.

BTW I hope your lagering is worthwhile and tastes a hell of a lot better than the Coopers Lager I did on half dex half ldme. OK I know it's an ale yeast but if the target flavour was correct then it's just thin, pale and slightly sour. No such problem with their draught, bitter, Canadian blonde and stout.

Cheers, Geoff.

My shed fridge is frost free and it has no trouble, admitadly its an old frost free so i dont no how much difference that would make and i can also say that the missus fridge inside is an lg frost free and you almost have to have the bastard turned right down to nothin just so it doesnt freeze things

[OldBugman]

same.

Got the freezer turned right down and then theres a vent lever for the ammount of air that is put into the fridge area.

[afromaiko]

Ripped the bugger apart and found out the return air vent to the freezer was blocked by a piece of foam that had moved when someone else previously serviced it. Fixing it up now, so hopefully that will make a difference.

[Shaun]

I just want to run this by others here that are fermenting in a fridge or freezer...

I'm about to brew a lager, so am giving my recently acquired brew fridge a dry run to check if it's capable. It's a fan forced model with the freezer on the bottom and using a Fridgemate thermostat.

I filled a fermenter with about 20 litres of water and put it into the fridge compartment. It took about 24 hours to drop from the initial ~20C down to 10C - which I'm planning to do for primary fermentation.

I've left it run for 48 hours now and it's dropped it to 3C but doesn't seem to be dropping much more. Is 3C going to be fine for lagering?

The fridge has been cranking away on full the entire time to get the temperature down this much. The fan forced model seems kind of inefficient, not much airflow really gets blown up into the fridge section. The freezer is plenty cool enough though.

I have thought about perhaps using the freezer section for lagering instead, but worried that it might be too powerful and end up freezing my beer. However, I can fit a 20L cube in.

How do the cooling rates above compare to other people's experiences?

thanks
Afromaiko

You want to brew it at 9-10*C, for lagering the best is between 1-2*C but 3 would still be fine and you would probably find it would drop to 1*C over a couple of days anyway, i have an old kelvinator and it has no trouble getting down to 1*C

I agree with lethal. Your temps should be fine.

[afromaiko]

same.

Got the freezer turned right down and then theres a vent lever for the ammount of air that is put into the fridge area.

Yeah, in the fridge section (on top) I have the thermostat supposedly for the fridge, then another 'thermostat' for the freezer.. which is really just a little vent that controls how much air flows into the fridge (or stays in the freezer).

In the freezer section there is the fan that blows the air up to the fridge, and next to it are two vents that circulate air around the freezer. Underneath this behind a panel is the evaporator coils that provide the cooling. Below this there is a return air vent that comes down from the fridge. This was blocked and now ok

If I block the two vents that blow air around the freezer I noticed that my fridge cool so much quicker. In fact I can stand there and watch the digital thermometer dropping before my eyes. I wonder if blocking these vents would have any negative effects on the freezer components? I don't want to damage anything.

I previously had thought that the freezer cooling would work independently when power was supplied, and that the fridge thermostat would cause the fan to come on and push cold air to the fridge when required. It seems otherwise in this Westinghouse model though. Everything runs when the fridge needs cooling - fan, compressor etc.

So it looks like I can't actually connect the Fridgemate into the fridge's thermostat connections and hope the freezer to run normally if I'm brewing up top at 10*C or higher. Lagering temperatures should be fine though. But I feel it's a shame to waste the freezer section..

[lethaldog]

The fridgemate controls power to the whole system so if your probe is in the fridge then when it reaches desired temp the whole system shuts down, as far as i know you cant iscolate 1 part from the other

[afromaiko]

The fridgemate controls power to the whole system so if your probe is in the fridge then when it reaches desired temp the whole system shuts down, as far as i know you cant iscolate 1 part from the other

That's right, I have a power socket wired into the Fridgemate and the fridge plugged in to that. But if you wanted to.. instead of wiring up a power socket you could connect the two relay terminals on the Fridgemate module to where your fridge's thermostat would usually connect.

It achieves the same thing I guess but is a bit neater and with some models *may* allow you to independently control the temp of the fridge without affecting the freezer.

In the last hour since I powered up the fridge after fixing the return air and then covering the other freezer cooling vents it's worked better than ever. Much more cold is pushed into the fridge section & it's dropped the air temp inside from around 25*C to -3*C in that short amount of time.

If it continues running ok, it seems like an easy modification to make your brew fridge a lot more efficient if you have a fan-forced type fridge/freezer combo and especially a bottom mount freezer model.

Hmm.. I think this hobby is starting to become more serious!

[danthebeerman]

I just want to run this by others here that are fermenting in a fridge or freezer...

I'm about to brew a lager, so am giving my recently acquired brew fridge a dry run to check if it's capable. It's a fan forced model with the freezer on the bottom and using a Fridgemate thermostat.

I filled a fermenter with about 20 litres of water and put it into the fridge compartment. It took about 24 hours to drop from the initial ~20C down to 10C - which I'm planning to do for primary fermentation.

I've left it run for 48 hours now and it's dropped it to 3C but doesn't seem to be dropping much more. Is 3C going to be fine for lagering?

The fridge has been cranking away on full the entire time to get the temperature down this much. The fan forced model seems kind of inefficient, not much airflow really gets blown up into the fridge section. The freezer is plenty cool enough though.

I have thought about perhaps using the freezer section for lagering instead, but worried that it might be too powerful and end up freezing my beer. However, I can fit a 20L cube in.

How do the cooling rates above compare to other people's experiences?

thanks
Afromaiko

This is what I use for lagering in a fridge to get it at the right temp. I also use one to convert a chest freezer into a fridge and keep my kegs at 1 degree.
Very easy to put togethor.

http://www.mashmaster.com.au/store/prod ... ucts_id=28

[TommyH]

Dont mean to hijack the thread but was just about to ask a question and it's related to this topic.
I have recently convinced my wife that our fridge and freezer need updating. Which means I get the old ones for my "brewery"
I've been looking at thermostat controls and have come up with these two models
http://www.mashmaster.com.au/store/prod ... ucts_id=84
http://www.mashmaster.com.au/store/prod ... ucts_id=28
Does anyone have a preference between the two?
I've noticed that the cheaper model can also control heating, but there is no reference to this for the dearer one. Also I don't know about inserting the probe in to the wort.(hygiene etc)
Also; do these units work ok on freezers? or would it be putting too much pressure on the compressor switching on and off.
Lastly, do these units have to be "hard wired" in to the fridge? Or can they be wired up to, say, a powerboard?

Any advice would be appreciated

Thanks for all your help.

Tommy

[danthebeerman]

They don't have to be hard wired to the fridge freezer. You get a 3 metre extension cord and cut it in half wire it to the unit along with the temperature prode that is included and then for safety reasons install it into a box that you can pick up at Dick Smiths or Jay Car.

You pluck 1 end into the power point and the other to the power cord coming from the fridge/freezer. You then set the temperature and place the temp prode into the fridge/freezer. It is very easy.

I use 1 for an old fridge that ferment lager yeasts at 10 degrees. My kegs are in a chest freezer and I have a twin tap coming out of the lid. The temp prode sits inside the chest freezer and the fridge mate is set at 1 degree. icy cold beer and it doesn't freeze. my chest freezer holds 6 kegs.

dan

[TommyH]

Thanks Dan.
Sounds good
Now all I have to do is get the new fridge/freezer

[geoffclifton]

You can call Frank at mashmaster, I did.

The more expensive controllers have a much higher grade probe and are dedicated coolers. The cheapier ($47) unit works fine but Frank will tell you that the probe will fail if immersed. No problem, we blue tack it to the outside of the tub. It's a great little device and works VERY well.

Cheers, Geoff.

[TommyH]

Thanks Geoff.
Think I prefer the cheaper version.

[lethaldog]

Thanks Geoff.
Think I prefer the cheaper version.

Cheaper version is great, i have one and have never had any probs with it

[TommyH]

Was waiting for :the dog" to reply
Thanks