# Heat Pads



## drsmurto (29/7/10)

I recently posed the question on another thread about the possibility of using a reptile heating pad instead of a brew pad.

Not much of a response so i decided to bite the bullet and be the guinea pig.

Standard brewing heat pads go for around $60 and are rated at 20-25W.

I bought a 20W reptile heat pad off ebay (see image below) for $30 plus postage - Link

I currently have a standard brewing heatpad running in a fridge out in the shed trying to germinate seeds. It is capable of holding a temp of 20-22C even with the night-time temp dropping to 0C. So i put the reptile heatpad to work in another fridge set to the same temp and let it equilibrate over a few days.

This morning both fridges read 21C.

Now i should add a few bits of information about this heatpad and also add i dont sell them and have no financial incentive for spruiking them other than to share what i think is a cheaper alternative. 

The reptile heat pad is flimsy. The first thing i thought of when i unwrapped it was a medical xray. Similar material, flexible and not the hard plastic that brewing heat pads are made from. Which means they aren't likely to be water proof but then i dont sit fermenters on heatpads anyway, i use them to heat the air in the fridge. 

As an aside, another test i have running is how hot a liquid gets when it is sat on top of a heatpad with no external thermostat control. Small scale test but a 250mL flask sitting on a standard 25W brewing heatpad with no insulation (ie not in a fridge but exposed to the night time temp) this morning read 28C - not the sort of temp you want to expose most beers to. I realise this is not representative of 20+L of wort in a plastic fermenter but it does give you an idea of the possibility of localised hot spots. I will up the scale to a 5L demi job and see what the actual temperature of the liquid gets to.

Hope that information is of some use to people....

Cheers
DrSmurto


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## Pennywise (29/7/10)

DrSmurto said:


> As an aside, another test i have running is how hot a liquid gets when it is sat on top of a heatpad with no external thermostat control. Small scale test but a 250mL flask sitting on a standard 25W brewing heatpad with no insulation (ie not in a fridge but exposed to the night time temp) this morning read 28C - not the sort of temp you want to expose most beers to. I realise this is not representative of 20+L of wort in a plastic fermenter but it does give you an idea of the possibility of localised hot spots. I will up the scale to a 5L demi job and see what the actual temperature of the liquid gets to.




When I started brewing I used a heat pad (the hard ones sold in brew shops), and I'll tell you now they'll get 23L of wort up to 24-26 degrees easily. Makes you wonder how hot the yeast cake would get, not something you'd want that's for sure. Like you though, in the event I actually need to use it I sit it on it's side and and heat the surrounding air.

Nice cheap alternative though those reptile heaters


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## vic45 (29/7/10)

I was using a heat pad, not sitting the fermentor on them in an upright freezer. 

Now I am using a small electric heater from big w. I get more even distribution of heat and hooked up to a tempmate the heater only runs for a very short time. 

I can have four fermentors going at the same time and the temp. never varies more than 1c 

It was the thought of hotspots that made me investigate the fan idea.


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## Fents (29/7/10)

do heat belts on fermenters delay fears about the yeast cake getting to hot?


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## bjay (29/7/10)

Now you blokes have got me thinkin about my nice hot yeast cake sittin at home  

Might have to look at other options ,,Does it make much difference 

bjay


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## Dazza_devil (29/7/10)

One of these looks like the goods for heating my conditioning cupboard in the winter, all I need is a thermometer and a thermostat or a temperature control unit. I suppose I could set it up with just a timer, thermometer and a little bit of tinkering.


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## RobB (29/7/10)

:icon_offtopic: 

I've used my heat-pad inside an esky and it gets the temperature into the mid-40's. I use it like this for making yoghurt.


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## outbreak (29/7/10)

Those heat cords at that ebay store look alright. You could run them around the walls of the fermenting fridge to get a nice even heat source (not that it would make that much of a difference). They are cheaper too. I think I may order one.


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## Linz (29/7/10)

another alternate heat pad is the heating pad from a water bed...the one I got from ebay has a temp controller on it and can set the beers to 20oC on the nose and have 2 fermenters at once


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## raven19 (29/7/10)

The convection caused from heat applied to the base of the fermentor would surely result in movement of liquid, hot wort rising, cool wort sinking and so on. (Understanding they wont necessarily be placed under the vessel)

A full scale test would be interesting Dr S.

Could I suggest that a lager yeast - being bottom fermenting - would be effected more than a top fermenting ale yeast?


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## Rod (29/7/10)

I use a heat belt available from your LHBS

and my Fridgemate from mashmaster

set fridgemate up on heating cycle and stick probe on the top side of the fermenter with bluetact

put the belt down on the bottom ridge of the fermenter

and away we go

the sticky thermometer is in the middle of the fermenter

both the fridgemate and the thermometer are within a degree after all settles down

KISS


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## drsmurto (29/7/10)

Rod - this heating pad is run via an ebay tempmate knockoff so both the fridge and the heat pad are plugged in and controlled.

Haven't seen the price of the heat belt but total cost for my setup

Fridge - free from freecycle - both my fermentation fridges are from freecycle :icon_cheers: .
Ebay tempmate - $35
Parts to wire up tempmate - $35
Reptile heatpad - $30 + $8 postage

Total = $108 give or take, not bad considering that everything other than the fridge itself is brand spanking new. :beerbang:


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## Hatchy (29/7/10)

I can't find my heat belt. I'm using a hot water bottle. I miss my heat belt.


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## RWithers (29/7/10)

i'm just using an immersion heater. No probs so far and it's keeping the brew a pretty constant 22C, but we'll se as time goes on with sanitation issues. I'm not too keen on having this foreign body sitting in my brew


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## mika (29/7/10)

I recently got one of those Infrared ceramic heat lamps that are also used in reptile enclosures. From the pet shops they're pretty dear, from e-bay you can get a 60W version for ~$25 of you look around a bit.
Means you have to buy a lamp holder that will accept a screw in bulb, so now my fridge is starting to get a little cramped.
Interesting to hear that a 20W heating element will get it there.
If I open the door at night, I see quite a drop from the 20deg setpoint and it seems to take several minutes to recover.
Have you noticed recovery time with the reptile heating pad ?
You don't open the fridge much, but still, interesting to know.
Looking at setting up a 2nd fermenting fridge, and the reptile pad seems a better thing.


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## Wolfy (29/7/10)

DrSmurto said:


> this heating pad is run via an ebay tempmate knockoff so both the fridge and the heat pad are plugged in and controlled.


I prefer to use the heater (either heat pad or belt) as a 'space heater' and sit it in the back of the fridge rather than attaching it too or under the fermenter.
Since my fridge is not so new and not 'fan forced' two 12V computer fans circulate the air inside so that the temperature (in heating or cooling mode) remains constant.


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## vic45 (29/7/10)

A $28 kambrook fan heater is super quick inside a freezer and a very even distribution of heat too.


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## drsmurto (30/7/10)

vic45 said:


> A $28 kambrook fan heater is super quick inside a freezer and a very even distribution of heat too.



Seriously?

What happens if/when condensation gets to the heaters exposed elements? 

I am not a sparky but that doesn't sound very safe to me.


Mika - i am not a very patient brewer so will open the door of the fridge daily at least to check how my babies are going. At this time of the year with such a massive temperature difference between inside and outside the temp drops rapidly by 3-4C but is back to where it was within 10 mins.


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## joshuahardie (30/7/10)

A an alternative to a heat belts and pads. I use the heating element out of a water bed.
It looks like a small camping mat, and is exactly the perfect height and length to wrap once around a fermenter. 
Obviously it is waterproof, has a graduated temp dial, and for greater peace of mind, I have it attached to a tempmate.

Just scavenged from a council pickup, but has worked perfectly for years.

Well worth keeping an eye out for.


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## Bjornwiser (5/8/10)

I've gone the way of the reptile heater attached to a temperature controller both from eBay, still putting it all together and testing bits n pieces. Any news from anyone who has completed one of these and any recommendations?

Cheers


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## beerbog (5/8/10)

joshuahardie said:


> A an alternative to a heat belts and pads. I use the heating element out of a water bed.
> It looks like a small camping mat, and is exactly the perfect height and length to wrap once around a fermenter.
> Obviously it is waterproof, has a graduated temp dial, and for greater peace of mind, I have it attached to a tempmate.
> 
> ...




Sounds like a good idea. :beerbang:


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## Daniel.lear (5/8/10)

If not willing to take risk do not read.

I am not an electrician.

But... LeathalCorpse look away now...

If your handy electrically and willing to play, you could try this:

Buy 6x 2.2kΩ 5W resistors;
scrounge a piece of a piece of thick, say 0.040", aluminium sheet;
240v power cable.

Connect 3 pairs of resistors in series and join the pairs together in parallel.

Hook active to one side and neutral to the other and affix to a piece of aluminium sheet with heat paste.

This will give you a heat pad for about 5 bucks @ a touch under 40watts. 

Brilliant!! I currently have 2 and not one burnt down house 

Be sure to earth and insulate where appropriate.


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## Banshee (5/8/10)

Leary said:


> If not willing to take risk do not read.
> 
> I am not an electrician.
> 
> ...



Can you post some picks or a diagram?
Wouldn't a 40w globe through the same heat and just as easy if not easier.


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## Daniel.lear (5/8/10)

Banshee said:


> Can you post some picks or a diagram?
> Wouldn't a 40w globe through the same heat and just as easy if not easier.



A lamp would probably be easier.

Here is something from paint


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## DU99 (5/8/10)

you can also use some heatsink to insulate..light can affect the wort..i wrap a towel around mine


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## Banshee (6/8/10)

Leary said:


> A lamp would probably be easier.
> 
> Here is something from paint



Ok, so you house the resistors in a pastic unit and screw that to the aluminium board. Where do you attach the neutral wire?
Does it have to be placed on the opposite end to where the active is or can it be attached anywhere?
Also I guess there is no earth for it.


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## bum (6/8/10)

You might as well just attach all of them to your sack. Save yourself some time.

Seriously.

Go buy one.


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## SpillsMostOfIt (6/8/10)

bum said:


> You might as well just attach all of them to your sack. Save yourself some time.
> 
> Seriously.
> 
> Go buy one.




... or do the exact same-ish thing and power it from a 12V halogen light transformer. Now, you're playing with lower voltages and less likely to remove yourself from the game when it all goes brown.

To paraphrase. If you're intent on playing the DIY heater game, why on earth would you not buy a downlight transformer with a molded-on 240V cord/plug and only have low-voltage inside your fridge?


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## drsmurto (6/8/10)

I started this thread to open up a discussion about a cheaper alternative to heating your fermentation fridge.

I didn't expect it to turn in to an all out MacGyver fest to see who could knock up the cheapest system using a few wires with the distinct possibility of featuring in the Darwin Awards in years to come.

Homebrewers are by and large, tight arses. A dollar saved and all that.

If you don't want to spend $30 on a heatpad you can get cheaper version which are lower wattage. If you dont have overnight temps of 0C like i do then maybe a 10W heatpad will do the job. Light globes, heat belts - all good.

But please don't put up this dodgy wiring guff that has the potential to cause someone harm. Whilst i am a big fan of natural selection and believe that it doesn't work fast enough in many cases, I'd hate to see a fellow brewer heading off to the big brewery in the sky before their time.

I can't wait for LC to arc  up over this discussion on dodgy wiring jobs.


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## Wolfy (6/8/10)

DrSmurto said:


> I started this thread to open up a discussion about a cheaper alternative to heating your fermentation fridge.
> 
> I didn't expect it to turn in to an all out MacGyver fest to see who could knock up the cheapest system using a few wires with the distinct possibility of featuring in the Darwin Awards in years to come.
> ....
> But please don't put up this dodgy wiring guff that has the potential to cause someone harm. Whilst i am a big fan of natural selection and believe that it doesn't work fast enough in many cases, I'd hate to see a fellow brewer heading off to the big brewery in the sky before their time.


Spoil sport. 

I just ordered some 24 SWG NiChrome wire, look at all the other fun things you can do with it: http://cgi.ebay.com.au/ws/eBayISAPI.dll?Vi...e=STRK:MEWNX:IT

Note: I'll be using mine for a boring, sane and sensible inoculation loop.


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## bum (6/8/10)

Wolfy said:


> I just ordered some 24 SWG NiChrome wire, look at all the other fun things you can do with it: http://cgi.ebay.com.au/ws/eBayISAPI.dll?Vi...e=STRK:MEWNX:IT


 
"It is a excellent choice for heating elements operating at temperatures up to 1100c" 

Sounds good for my Farmland lager toucan.


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## Peter Wadey (6/8/10)

Hello Smurto,

I agree with SpillsMostOfIt.

I have a ~25W 12V dc powered resistive array mounted across the output of a 12V dc fan.
The 80-100mm dia. fan is attached via a bracket to the inside side of the fridge.
The supply to the (fan + resistive array) is switched by a thermostat.
This provides gentle heat to the interior of the cabinet.

Rgds,
Peter


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## drsmurto (6/8/10)

No issue with what SMOI proposed nor yourself. Low voltage is a sensible approach.


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## Fents (6/8/10)

hurry up LC i want to see some scolding.


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## Daniel.lear (6/8/10)

I must admit I was hoping to sit back with some popcorn too, alas no such entertainment.

FWIW, I concur with the good Dr et al, low voltage is the superior option if your going to make your own heater.

You did ask for cheap though...  

Leary


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## philmud (20/4/13)

Dr Smurto, a couple of years on, are you still using the reptile heater option? How's it working out if so? Looks like a good budget option to me. I also have a dumb question re: any kind of in-fridge heat option plugged into an STC1000. Does the power cord affect the seal of the fridge? The STC temperature probe is so thin, but it seems that a power cord would be more of an issue.


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## wbosher (20/4/13)

Phil Mud said:


> Dr Smurto, a couple of years on, are you still using the reptile heater option? How's it working out if so? Looks like a good budget option to me. I also have a dumb question re: any kind of in-fridge heat option plugged into an STC1000. Does the power cord affect the seal of the fridge? The STC temperature probe is so thin, but it seems that a power cord would be more of an issue.


I use a heat belt sitting in the fridge, not around the fermenter just sitting beside it, and the stc-1000 probe inside the fermenter. The power cord doesn't seem to have any detrimental effect on the seal at all.


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## drsmurto (21/4/13)

Phil Mud said:


> Dr Smurto, a couple of years on, are you still using the reptile heater option? How's it working out if so? Looks like a good budget option to me. I also have a dumb question re: any kind of in-fridge heat option plugged into an STC1000. Does the power cord affect the seal of the fridge? The STC temperature probe is so thin, but it seems that a power cord would be more of an issue.


The reptile heater is still going strong. A very good investment IMO.

Yes, the power cord does impact on the fridge door seal but it's minimal and regardless of what you use to heat the fridge with you need to get a cord in their to power it.


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## philmud (21/4/13)

Thanks Doc, I think I'll grab one of these


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