heat belt burning

[thisispants]

So I took everyone's advice and put the heat belt in the bin. I bought a 4m 15W reptile heating cord today. I tested it out in the kitchen and it doesn't seem to get particularly hot so I've just draped it around inside the fridge..... I'm a bit concerned it's not going to heat the fridge enough. Tonight is the test I guess.

 

[Tex N Oz]

So I took everyone's advice and put the heat belt in the bin. I bought a 4m 15W reptile heating cord today. I tested it out in the kitchen and it doesn't seem to get particularly hot so I've just draped it around inside the fridge..... I'm a bit concerned it's not going to heat the fridge enough. Tonight is the test I guess.

That was a smart move mate. Your safety and the safety of your family is always #1. No electrocutions and no house fires means we might get to live another day to enjoy another home-brew.
So regardless of the outcome, it's by all standards the best move you could have made.

Now on to the new heat tape.

As long as the heat input from the from the new belt is greater than the heat loss through the insulation of your cabinet, you'll notice a definite rise in temperature. You will notice a loss in effectiveness when the temperature difference between the conditioned air temperature (inside the refrigerator) and the ambient air temperature (outside the refrigerator) becomes greater. This isn't to say it won't work, but it might take a little bit longer. If the temperature difference it too great, it might not be enough to work at all as heat transfer is greater at a larger temperature difference and the output of your heater might not cope. Geez I hope that makes sense. Anyway, I'll take my nerd hat off and say that when it gets too cold outside it might not keep your brew warm enough.
Regardless, 15W is not a lot of heat and it might be very slow to react. Come next winter, you'll most likely need something with a bit higher output but that is all on condition of how well your refrigerator is insulated.
If you need help in the future to size something up, let me know and I'll help you.

 

[Danwood]

So I took everyone's advice and put the heat belt in the bin. I bought a 4m 15W reptile heating cord today. I tested it out in the kitchen and it doesn't seem to get particularly hot so I've just draped it around inside the fridge..... I'm a bit concerned it's not going to heat the fridge enough. Tonight is the test I guess.

I wouldn't worry. I think mine is a 3m model, and definitely 15W, and has no problem heating my setup to normal ferm. temps. (Low 20s for D rest), even in winter.
My temp. sensor is on the outside of the SS vessel, under the foil bubble wrap.
I usually put the no-chill cube in the ferm. fridge for a day at 20C, then by the time I've transferred to the FV and applied O2, it's at 17-18C and ready to for the pitch.
As Tex said, the fridge insulation will vary, as will the thermal mass in your FV (ie starting it off at the required temp, and how well your FV fits your fridge, with as little wasted fridge space as possible).
If you do have issues, maybe wrap the cord around the FV, then move it back to the walls once you've hit your temp.
Hope it all goes well anyway.

 

[Tex N Oz]

I wouldn't worry. I think mine is a 3m model, and definitely 15W, and has no problem heating my setup to normal ferm. temps. (Low 20s for D rest), even in winter.
My temp. sensor is on the outside of the SS vessel, under the foil bubble wrap.
I usually put the no-chill cube in the ferm. fridge for a day at 20C, then by the time I've transferred to the FV and applied O2, it's at 17-18C and ready to for the pitch.
As Tex said, the fridge insulation will vary, as will the thermal mass in your FV (ie starting it off at the required temp, and how well your FV fits your fridge, with as little wasted fridge space as possible).
If you do have issues, maybe wrap the cord around the FV, then move it back to the walls once you've hit your temp.
Hope it all goes well anyway.

Hey Dan,
That leads me to a question of my own hopefully not to get off-topic here.
I am anything but a proficient brewer. I'm way more into the equipment, environmental controls side of this process.
Let's say I've got a 23 litre FV @ 16°C and I'm heading into my D rest. Lets say I'm heading for the low 20's. Perhaps 23°C.
If I want to raise the temperature of that 23 litres with 15W and it's direct heating not taking into account any heat loss to the outside whatsoever, The minimum time to rise will be 12.5 hours.
Now taking into consideration the heat loss and rate of heat exchange through the vessel it will more than likely take 24 to 36 hours.
How will this affect the process since the D rest is usually performed at the very end of fermentation? Perhaps I should start this on another thread because I've built some prototype cabinet heaters that try to make this change happen very quickly and accurately. I'm really good at over thinking ****.

 

[thisispants]

It worked a treat last night! Very happy, it's a very slow gentle heat but it worked very nicely. I'm not sure how it'll go in the middle of a Canberra winter, but certainly I'm good for another 9 months or so. A win! Thanks everyone!

 

[Danwood]

*Snip, snip, snip*
I'm really good at over thinking ****.

I believe you, Tex (jus' joking).

I raise the temp by 0.5C every other day after the first 2 days (depending on how quickly the yeast is chewing through, sometimes ramping up every day if it's a beast). Starting at 17-18C and finishing ~21-22C.
This would obviously be different for lagers with the bigger temp. gap, but I don't brew lagers so I'm not sure how you'd go?

I'm no expert either, but a sudden hike in temp. as you mentioned, is generally not much good for yeast. There are more knowledgable blokes around here who could weigh in.

If you wanted to ferment an ale at 16C (with that yeast profile), I would probably give it half the predicted ferm. time at that and then start moving the temp. up by a degree every other day. Again, others will likely have more experience with this.
Anyway, this method seems to be working nicely for me.

Cheers

 

[Tex N Oz]

I believe you, Tex (jus' joking).

I raise the temp by 0.5C every other day after the first 2 days (depending on how quickly the yeast is chewing through, sometimes ramping up every day if it's a beast). Starting at 17-18C and finishing ~21-22C.
This would obviously be different for lagers with the bigger temp. gap, but I don't brew lagers so I'm not sure how you'd go?

I'm no expert either, but a sudden hike in temp. as you mentioned, is generally not much good for yeast. There are more knowledgable blokes around here who could weigh in.

If you wanted to ferment an ale at 16C (with that yeast profile), I would probably give it half the predicted ferm. time at that and then start moving the temp. up by a degree every other day. Again, others will likely have more experience with this.
Anyway, this method seems to be working nicely for me.

Cheers

Thanks for that mate. There's a lot to learn and I should probably learn what my process should be long before I start building gear. haha
That would make sense to have a slow ramp up as the yeast aren't fond of change.

 

[n87]

It worked a treat last night! Very happy, it's a very slow gentle heat but it worked very nicely. I'm not sure how it'll go in the middle of a Canberra winter, but certainly I'm good for another 9 months or so. A win! Thanks everyone!

I have a 50W 6m one, i got bigger cause i have a ~500L upright freezer, and i can fit a 60 and a 30 fermenter in at the same time.

It had no trouble getting two batches (at the same time) up to a 21C D rest during the NSW cold snap (overnight here was 0C or below for a few nights)
Not a Canberra winter... but still


I have this one:
http://www.reptiledirect.com.au/p/89/GCE-102-Heat-Cable-50W-6m.html

it runs the full height of the freezer in each corner. so a nice ambient heat.

 

[Tex N Oz]

I have a 50W 6m one, i got bigger cause i have a ~500L upright freezer, and i can fit a 60 and a 30 fermenter in at the same time.

It had no trouble getting two batches (at the same time) up to a 21C D rest during the NSW cold snap (overnight here was 0C or below for a few nights)
Not a Canberra winter... but still


I have this one:
http://www.reptiledirect.com.au/p/89/GCE-102-Heat-Cable-50W-6m.html

it runs the full height of the freezer in each corner. so a nice ambient heat.

I used a 100W ceramic heater and an old CPU heatsink and fan. Was cheap as chips to build and works great but probably more power than I need here in Sydney winter.
It does help move the air around too but not sure that's really necessary.

 

[n87]

I used a 100W ceramic heater and an old CPU heatsink and fan. Was cheap as chips to build and works great but probably more power than I need here in Sydney winter.
It does help move the air around too but not sure that's really necessary.

I should really hook up a fan in my freezer, there is a temp difference between the top fermenter and the bottom