Fermenting Fridge Temp Probs

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Jez

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Hi,

I have been using my fermenting fridge in my shed for a couple of brews with no probs. Fridge is hooked up to an external temp contoller (made with a Tobins thermostat) with as much of the probe in the fridge as possible. Have been setting temp at 18-20C for extended periods and fridge has kept close to that temp with no probs.

Last 2 brews the temp stays at 18C-20C for 2 days then the fridge temp drops to 10C for a few days.

Anyone else have this prob before?

Is this a sign the fridge is on the way out? or that my Thermostat is on the way out?

Thanks

Jez
 
Hey Jez,

I am also running a Tobins thermostat, but inside the fridge. It was easy as to replace the original thermostat, just had to undo 3 screws and remove 2 connectors.

I haven't had any problems with the temperature stability, but then again the whole probe is in the fridge. It is a very old fridge too.
 
Probably a stupid reply, but are you sure that the thermo is hooked up properly.
If the wires are around the wrong way it will come ON when the temp drops below your set temp.

You can easily test this by plugging a desk lamp into the controller. With a bit of ice and a glass of warm water test see if it coming on when the temp rises above the set temp.
cheers Darren

(I know about this because I had a reptile heater that I tried to use as a fridge controller. I simply changed the wires around and now it cools rather than heats

cheers
Darren
Jez said:
Hi,

I have been using my fermenting fridge in my shed for a couple of brews with no probs. Fridge is hooked up to an external temp contoller (made with a Tobins thermostat) with as much of the probe in the fridge as possible. Have been setting temp at 18-20C for extended periods and fridge has kept close to that temp with no probs.

Last 2 brews the temp stays at 18C-20C for 2 days then the fridge temp drops to 10C for a few days.

Anyone else have this prob before?

Is this a sign the fridge is on the way out? or that my Thermostat is on the way out?

Thanks

Jez
[post="61552"][/post]​
 
Whats the ambient temp? I would have no chance of keeping my fridge (same thermostat) up at 20 deg now that ambient temps are dropping well below 10 deg at night.

Infact just yesterday I had to rig up a heat box in the fridge to get temps up to fermenting temps rather than cooling down as it did in the warmer months.

Edit: Just noticed your in panania.. a local ;)
No way will you be able to maintain 20 deg without heating overnight.
 
Jez,

What is the outside temp dropping to at night??

Could this be your problem...
 
Yep,

Ecounter the same problems fermenting in my fridge in winter. First 3 days of vigorous fermentation generate enough heat in a sealed fridge to keep things copacetic. However as fermentation dies off the heat dissipates and outside temps dictate that things cool down.

In winter I take my fermenters from the fridge when primary fermentation starts to abate and put them in a warming cabinet. Nothing more complicated than a sealed box with a 40 watt lightbulb. One day I'll endeavour to rig up something more sophisticated. :D

Warren -
 
i have my lager sittin in the freezer outside and it was pluged in for the first few days, not sure if it even turned on, i unplugged it and forgot to plug it in again.... i thought dam screwed the beer, looked at my temp logging data and its been around 8-9deg for the first few days (plugged in) then sat at 9-10deg for the rest of the time

WOO HOO
 
Hey Jez,
Not telling you to suck eggs or anything, but do you have a heating light set up on the thermostat? I just didn't notice it mentioned in your post.
If not this Circuit Diagram may help. This is what I will be doing when I get my Tobibs Thermostat. :beer:
 
ahh yes. it has been bloody cold lately.

Thanks everyone. seems obvious now :rolleyes: .

looks like I'll be adding a lightbulb to my setup with a switch as per Justins great instructions.

Thanks again.

Jez
 
On the subject of heating our fridges....

Since beer is affected by light, is there any particular colour of globe that wont be a problem to use instead of housing it within a box?

Reason being I would think the globe while enclosed will get many more hot/cold cylces & far more frequently than usually intended & would most likely substantially shorten its life.

I was thinking maybe a red globe or blue might be ok?

Another thing i was wondering is are there globes that generate more heat than others of the same wattage?
 
Killer,

I've been using a 40 watt clear globe for a few years. Initially I had reservations out the myths of mercapitans and lightstruck beers. However I've never noticed any effects. I believe that beer can only be lightstruck with UV.

So regular bulbs are OK. However I think that fluoros could be another issue.

Warren -
 
Just paint the globe you want to use, black would be best, but any other colour will do. For this you dont want a high power globe, 25W tops. This way you transmit the heat, and actually end up turning some of the light into more heat.
 
How about a set up of Infra Red LEDs or just one of those heating globes?
 
I Just looked up some heat lamps (I conveniently work for a electrical supply chain) & it appears they are UV lamps. Isnt this the light we want to avoid?

I think i will stick to the 60w lamp in the small ply box, seemed to work well overnight.
 
We woke up to 3.5degC yesterday morning and the Strong Ale I was fermenting was down to 14degC in the ferm freezer and bubbling a bit slow.
I had a heater pad (30W) that wasn't being used so I connected it to a timer and threw it in alongside. 15 min on then 2 hrs off seems to be working. When it was on fulltime it was getting a little warm.


I control my chest freezer with one of the Jaycar units but I would only recommend it to somebody handy with a soldering iron.

http://www1.jaycar.com.au/productView.asp?...eMax=&SUBCATID=

I went down this path because my freezer has a wierd thermostat that I couldn't remove for fear of wrecking it (and getting bitten by something nasty lurking underneath :eek: )

I removed the thermistor (temperature sensing component - looks like a small blue capacitor) and put it on 500mm of wire which I fed into the freezer. The device is purley resistive and not effected by the extra capacitance of the wire as somebody suggested in a previous thread.
Connected the mains thru' the NC (normally closed) contact because the thermostat is designed for heating. ie freezer turns on when thermostat turns off.

Downsides :( of this unit are:
- It displays 'HEAT' when the freezer is actually off but I can live with that.
- If the thermostat malfunctions (stops) it will freeze everything inside.
- It runs off 2 x AAA battreries so I had to build a powersupply - had the parts lying around anyway.
- Only handles 3A inductive loads - my freezer has 1A surge (125W motor) so ok.
- 5 to 30degC range - ok for me, lagers go in the other fridge.

On the good side :D it constantly displays the current temp inside the freezer, you can reliably set an exact temperature to 0.5deg resolution & it's very easy to operate.
It has a 'deadband' hysteresis of 1degC (+/- 0.5deg from set point). On a warm 30deg day the pump turns on for 10 or so mins then off for about 45. This may stress the motor slightly more than usual operation but with an old freezer that cost nothing who cares.

Also added a 12VDC fan from an old computer for air circulation but I think it's mentioned elsewhere before also.

Would I go down this path again? Definitely.
 
KillerRx4 said:
I Just looked up some heat lamps (I conveniently work for a electrical supply chain) & it appears they are UV lamps. Isnt this the light we want to avoid?
[post="61637"][/post]​

Heat lamps are usually infra-red, so there should be very little to no UV light coming out (opposite ends of the spectrum).

If you are just using a standard light globe, a red one would be better than a clear (or blue) one, they are pretty easy to find in the supermarket or bunnings etc.
 
Wortgames said:
Heat lamps are usually infra-red, so there should be very little to no UV light coming out (opposite ends of the spectrum).

If you are just using a standard light globe, a red one would be better than a clear (or blue) one, they are pretty easy to find in the supermarket or bunnings etc.
Or better still, one of those Darkroom brown lights. They are a terrible colour, but don't put out much light, so it wouldn't effect the beer if you are that worried, but should put out enough warmth.
 

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