Problem with brew fridge

[Clint]

A trick I use which works wonders is to put one or more containers with hot water in the dead space of the tall fridge. Just 50c tap water will do it, I have a 12L fermenter but anything will work, like a stock pot or anything that will fit. That acts like a second heater and helps keep the temp up due to the thermal mass of the water. I usually use it for kveik and if you leave some head room in your "heater", once the water temp starts to equalise you can just top it up with a couple of kettles worth of boiling water.

Great idea. A chap in work will fill a couple of Jerry cans with boiling water and put them in his car on a frosty night to save him messing about at the end of the shift..

 

[Libigage]

Just a thought....how have you got the temp probe from the Inkbird?

Inkbird probe

 

[Libigage]

I'm beginning to wonder if my heater might have had a temporary failure as it has been a constant 18.6 with the Inkbird set at 20. It's bubbling away nicely every second via a blow off tube. I've got a heater pad being delivered today so I might swap it with the tube just to be safe. Its only 25 Watts but as the FV sits directly on top am I right in believing it should be OK on its own or should I use both.

 

[Wynne]

I agree with @Bill_g, only plug in the heater to avoid the fridge cutting-in if the temperature overshoots - that’s what I do (and the converse when the ambient temperature is higher than fermentation temperature). You could also try to put a false ceiling made from expanded polystyrene or similar or even cardboard into your fridge just above the fermenter to reduce the volume that the tube heater has to heat.

 

[LED_ZEP]

'm beginning to wonder if my heater might have had a temporary failure as it has been a constant 18.6 with the Inkbird set at 20. It's bubbling away nicely every second

It could just be that the ferment having now kicked off is exothermically producing that extra few of degrees of temp.

 

[Bill_g]

I'm beginning to wonder if my heater might have had a temporary failure as it has been a constant 18.6 with the Inkbird set at 20. It's bubbling away nicely every second via a blow off tube. I've got a heater pad being delivered today so I might swap it with the tube just to be safe. Its only 25 Watts but as the FV sits directly on top am I right in believing it should be OK on its own or should I use both.

I can't see any harm in using both. Essentially if ambient temp is low you are losing more heat to ambient due to the larger than usual difference in temperature. So more heat energy in is required. Both heaters are low power so local overheating of the beer seems very unlikely.

 

[The-Engineer-That-Brews]

You could also try to put a false ceiling made from expanded polystyrene or similar or even cardboard into your fridge just above the fermenter to reduce the volume that the tube heater has to heat.

Trust me, it doesn’t work like that.
Changing the temperature of a volume of air takes a negligible amount of energy, so everything inside the fridge will be at the same temperature.
What you have to do is prevent the rate of heat loss to the environment - so that means either (a) lagging the outside of the fridge; or (b) lagging the fermenter AND heater (combined) inside the fridge.
You could do (b) by putting the fermenter and heater together in a picnic box inside the fridge, for example, but it’s probably easier and cheaper just to wrap the whole fridge in an old duvet (but leave the condenser elements free, obvs)