How to Set up a Water Bath for your FV

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terrym

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How does it work with the water bath? Is the temperature even, or is it warm near the heater and much cooler opposite it?
From memory whenever I've taken temperature readings across the water bath at different points the difference is usually no more than about 0.5*C. What I can't do however is test the difference from top to bottom of the bath.
 

Llanbrewer

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From memory whenever I've taken temperature readings across the water bath at different points the difference is usually no more than about 0.5*C. What I can't do however is test the difference from top to bottom of the bath.
Aquariums must have a pretty even temperature despite having heaters just stuck in one corner. However, I find it difficult to understand how this happens because when topping up a bath, it's necessary to swish the water round to get it from the tap end to the other end. The answer must be that with steady heating, the convection currents are sufficient to evenly dissipate the heat.
 

terrym

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The answer must be that with steady heating, the convection currents are sufficient to evenly dissipate the heat.
That's how I read it, probably because the fairly narrow water bath annulus (certainly in my set-up) is conducive to convection currents being formed.
 

terrym

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Well I'm certainly not 'worried' about an apparent temperature difference of <0.5*C across my water bath.
It's got an FV with beer in it, not a nuclear reactor!
 

Bigcol49

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Well I'm certainly not 'worried' about an apparent temperature difference of <0.5*C across my water bath.
It's got an FV with beer in it, not a nuclear reactor!
Hi!
What a put down!
I knew that you wouldn't be worried with such a low temp difference; I posted for the benefit of anyone who was worried.
I've read posts about brewers who have recorded a large vertical temperature difference in their water bath - this may happen if the setup involves a large volume of water in the bath. A cheap submersible pump solved their problem.
I suppose it's the same situation with having or not having a circulationg fan in a brewfridge.
 

terrym

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The water bath idea is very low tech; you have only got to look at my set-up in the OP to see that. The fish tank heater itself relies on a fairly crude thermostat and that in itself introduces a small working temperature variation local to the heater let alone elsewhere. In my opinion therefore, by its very nature, there is no need for any extra bells and whistles. You can't polish a ****!
However, it does allow homebrewers to maintain fermenting temperatures with reasonable accuracy in a 'simple, cheap and effective' manner when otherwise they are unable to do that for space or background temperature reasons.
So anyone who is fastidious about maintaining brewing temperature control to very fine margins, should be probably be looking at other more sophisticated methods.
However I am sure that for many like me it does the job it is intended to do.
 

Bigcol49

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Hi!
I stand corrected. In future, I'll refrain from sticking my nose in where it's not wanted.
 

Martyn53

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Hi

I tried this and it's a great idea, but I think I've been unlucky with buying the heater (both from Ebay, one was direct from China). The first lasted five minutes and the other managed one successful brew before giving up the ghost.

So could anyone recommend a reliable brand and/or supplier for the aquarium heaters?

Thanks
 

terrym

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Hi

I tried this and it's a great idea, but I think I've been unlucky with buying the heater (both from Ebay, one was direct from China). The first lasted five minutes and the other managed one successful brew before giving up the ghost.

So could anyone recommend a reliable brand and/or supplier for the aquarium heaters?

Thanks
All I can say is I have had a 50w version of one of these off ebay which I have had for 18months and used throughout the colder months of the year. It's on as I write :thumb:

PS If you bought from a UK seller you have consumer rights and could go back to the supplier under faulty goods especially if the seller is a 'reputable' aquatics company. Might be worth a try.
 
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Ale

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Great posting, I did this for the first time last winter and it made an incredible difference to my brews - a real consistent ferment right down to 1010 in most cases. I now almost prefer brewing in winter rather than summer fluctuating room temps, in fact I now stop brewing June-Aug.
This thread was back on top of the How to's today. I was thinking about this earlier as a lot of people seem to be saying they use the trub and water heater set up. Cooling in summer is even easier than keeping it warm in winter. All you have to do is put your FV in the water bath and put a t shirt over the FV. The t shirt wicks the water and as it evaporates that cools the wort. Last summer even on the hotter days my beer stayed at 20°C.

Before the t shirt trick it was 25°C+ with the FV not in water once fermentation started, in the garage. I caught it on the first day of fermentation and did some frantic googling and found the t shirt solution. Even though it got warmer outside once I put it in a trub with the t shirt over it it kept it perfect at around 20°C. Try it with water if you want to before risking a brew, but of cause you wont have fermentation creating heat.

EDIT: I cant guarantee you will have exactly the same results as me. It worked very well for me though. Dont blame me if you try it and it goes wrong, but I think it will work.
 

Martyn53

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All I can say is I have had a 50w version of one of these off ebay which I have had for 18months and used throughout the colder months of the year. It's on as I write :thumb:
Thanks Terry

That looks, branding aside, pretty much identical to the two that I tried, so I guess it's one of those products that's made to a higher or lower quality spec depending on the reseller. At least I've got a brand to look out for now, thanks again.
 

dps51

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I use a f1sh tank heater which you can get from any pets at home shop
works for me
 

Aphid

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Hi

I tried this and it's a great idea, but I think I've been unlucky with buying the heater (both from Ebay, one was direct from China). The first lasted five minutes and the other managed one successful brew before giving up the ghost.

So could anyone recommend a reliable brand and/or supplier for the aquarium heaters?

Thanks
I bought mine from a local fish/aquarium shop. Cost me £11.00. Came with a guarantee and the reassurance that, should there be issues, I could call back into the shop and sort it. That said, it has worked well for me for several brews, one being a Saison that required 27C.

IMG_0502.jpg
 

Martyn53

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Judging by the reviews on the Pets At Home website, it's hit and miss whether you get one that actually works or not, much like my own experience.

I think trying a local shop might be the best idea, thanks all for the help.
 

flamenco

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I have been using the water bath and fish tank heater thing for 4 years. I have a large plastic container (Poundland type shops have them for a couple of quid) and pour the sanitiser from the FV into the tank as the water. It is already at 22c and is going to stay clean. The thermometer is in the FV until the correct temp for the yeast and then I put it in the water bath to monitor temps throughout fermentation. Two sleeping bags - one around the bath and one across the top. Once the yeast has got going, I don't touch it for usually 2 weeks. Works very well. I tip the water away for the next brew and repeat with the sanitiser from the FV and start again.
 

Broomie14

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Im getting my trug tomorrow so i will be using this technique in the next week or so is it necessary to wrap it in towels/sleeping bags or will i get away with out that as its going to be done in the spare bedroom??
 

terrym

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Im getting my trug tomorrow so i will be using this technique in the next week or so is it necessary to wrap it in towels/sleeping bags or will i get away with out that as its going to be done in the spare bedroom??
If it's a lot colder outside the water bath compared to inside it, then the added insulation provided by wrapping in towels or a sleeping bag will probably keep temperatures more stable. And you might save a few pence in electricity.
In the end it's your choice. :thumb:
 

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