Fermentation Chamber Up And Running.

[Greg2013]

The requirement for the freezer part of these cabinets is minimal as if they are in garage it's only lagers in high summer, not ales in mid winter, even inside best not to locate freezer next to the cooker.

Please advise Greg how he can calculate the thermal mass of his wort and thermal inertia of his fridge?

What is best though matters not so much, what is best with what you have is what matters i think. I have the temperature differential set at 10 minutes, as CH knows my chest freezer is in my kitchen away from any heat source, the probe will be taped to the side of the carboy sandwiched between two layers of bubble wrap or directly into the wort depending on what i am brewing.

AFAIK you cant put multiple probes into an stc-1000, if you can then yes i agree 2-3 probes would be great setup.

[Will_D]

Also glass is a poor conductor of heat so fermentation being exothermic does not make much of a difference.

Glass is a much better conductor of heat than plastics. !!

It is worse than metals!

[Greg2013]

Also glass is a poor conductor of heat so fermentation being exothermic does not make much of a difference.

Glass is a much better conductor of heat than plastics. !!

It is worse than metals!

Plastic is a good insulator of heat hence why picnic coolers make great mash tuns etc, glass is a great conductor of heat hence why glass carboys make good fermentation vessels as the allow the heat to escape and not bake the brew 

[Stitch]

Glass is a much better conductor of heat than plastics. !!

It is worse than metals!

Agreed Will the thermal conductivity of glass is 4 times that of plastic. Copper is 400 times the thermal conductivity of glass!!!
That is why I said it is a poor conductor of heat.

Think of all the insulation based materials that are made from glass!!!

Plastic is a good insulator of heat hence why picnic coolers make great mash tuns etc, glass is a great conductor of heat hence why glass carboys make good fermentation vessels as the allow the heat to escape and not bake the brew 

I disagree with the Greg. I would not say it is a great conductor. It is better than plastic but copper is a great conductor. I would still rank glass as being poor.

The important fact about a fermentation chamber is that the ambient temperature is stable.

Air has a really low thermal conductivity 10 times less than plastic.
I just don't see the benefit of putting the probe under an insulator. Like I said it will cause the freezer to run longer. Keeping temperature of the air constant is really all you can hope to achieve with a fermentation chamber. Then naturally the wort/beer will reach thermal equilibrium over time.

Heat given off by fermentation will equalise with the air in the chamber therefore wort temperature drops as air temperature equals until they are both even.

Also just to not if you wish to add extract sensors to the STC-1000 you must arrange them as a wheatstone bridge. You can then connect multiple sensors into one port.

[Ciderhead]

Ok as i said I have seen others do it and am going to come back in a couple of weeks and show you why you need it under a thermal insulator

[Greg2013]

Comparitively speaking between glass and plastic glass is a great conductor.  Copper is better of course but out of reach  of a lot of home brewers due to price of raw material, unless of course you happen to drive a BMW estate 

[Ciderhead]

unless of course you happen to drive a BMW estate 

FO its a merc now and you've seen it twice ya blind old git 

[Greg2013]

unless of course you happen to drive a BMW estate 

FO its a merc now you've seen it twice ya blind old git 

Sorry i thought that was the wife's car 

[Greg2013]

All joking aside though (for now) if not down into a pint glass of water and not down into the wort ( and not up my ass), where and how CH would you setup that probe ? You will have to explain that Wheatstone bridge thing to me next time you are around 

[Ciderhead]

unless of course you happen to drive a BMW estate 

FO its a merc now you've seen it twice ya blind old git 

Sorry i thought that was the wife's car 

............................................... is the sound you hear when the phone hangs up.

[Greg2013]

Stop trying to confuse me with cryptic answers CH you know my old brain can't handle that kinda pressure 

[pob]

The main reason you place the probe under some insulation, is to dampen the readings for the STC.

The STC is taking continual readings, at a much higher rate than the rate of change of either the air or wort mass reacting to a change in temperature input (either heating tube/bulb or the fridge).

If the wort could react to change of temp as quickly as you made the change, then you could leave the probe anywhere in chamber.

Otherwise as there is a catchup phase for the wort, the STC needs to provide a bit more heat/cooling (over your target temp) to enable wort to change temp and bring it towards your target temp.

In effect you are using the insulation as your correction factor in a manual, non measured PID type effect for your STC.

Hope that's as clear as mud.

[pob]

An alternative to STC might be an Arduino running multiple probes (air temp, in FV temp, outside FV temp).

Then using Arduino PID sketches you could get that (through relays) to heat, cool & switch a PC fan on/off, when temp differentials between the probes arises.

Really just IF..THEN routines based on what temp tolerances you want to use (obviously stick a time delay on cooling circuit to protect fridge).

Roll on the Brauduino Mk 2.

[Ciderhead]

Or brewPi

[pob]

Oh, You got it up ang working