thermopot fermentor

[Fil]

Bergland have delivered the replacement thermopot and its perfect inside, So the build is on.

Ive been convinced that chilling is best sorted thru a square ss coil thru the lid with a shelf chiller providing the chill.

so do i pull the coil so its not just in a single plane or will that screw it up?

Ebay turned up trumps giving me 2 10mm swaglock x 1/2" SS fittings for a fiver

however the ebay seller of the SS deck fitting i opted for ignored my emails and forced me to open a dispute as its still not here.. so mk1 will be tapless and i will syphon out..

So Heating?? first, will it be necessary? will 60L+ of beer maintain a fermentation temp on its own in colder ambient conditions if inside a thermopot?? even need chilling ??

I seem to recall reading about a large volume (compared to 25l) maintaining a temp 4c above ambient but cant track that down now i need it

if heating is needed, i have been pointed at reptile heat pads, found one circa 30 cm x 20 cm rated at 40w with mains power and a control knob?
alternativly a lower wat budget option is motorcycle handle grip heat pads at about 3w each for a 15cm sq area.

a premium option is the thermofix heat trace cable at 10w per m..

I am also considering using a small cartridge heater to heat the chiller water bath so enabeling me to use the cooling coil for applying heat too? tho i can see that being a bit of a control nightmare limiting the waterbath temp to something not too harsh 30C while also monitoring the fermentation temp.

before i take off the pot bottom it would be good to know that i need to
appreciate any n all input

[barneey]

Fil, as you might be aware I use the maxi + cartridge heater on the same loop, in my experience as long as the probe is measuring actual liquid temps inside the fermenter it WILL not cycle hot / cold very much due to the thermal mass of the liquid. In order for the idea to work though it does depend on a couple of points :-

Never have the maxi ON constantly only when cooling is required, the maxi pump has to wired separately through relays so its independent of the heating and cooling side of things, a small maxi chiller is better suited to this setup as it cools down a lot quicker than a larger model.

Any thanks to Wallybrew for the original idea.

[Fil]

what size cartridge heater? i have a 2 product chiller with an agitator im planning to replace with a small fountain / pond pump.

i did dbl check your fridge and chiller dual control thread but didnt see any mention of heating,

do you have anything like this inline
http://www.sinolec.co.uk/thermal-fuses- ... losed.html

to ensure you dont overheat the water bath and apply too vigorous heat

So using an stc1000 or similar i have the compressor wired thru the chill relay, and the heater via the heater relay,

But if i have the pump live connected to both heating and cooling relays wont that then switch both heating and cooling on at the same time whenever one is activated?

how do i wire pump to run when either heating or cooling is running but not when neither are needed?

seems like i need a sympathetic relay?

[barneey]

viewtopic.php?f=6&t=60518&hilit=+maxi

Its just a standard 150watt radiator heater housed within a 1/2 homemade tube.

A couple of relays will (are necessary) isolate the cooling / heating side of things + an STC controller.

Since the build I`ve also added a few more relays to control the freezer with the STC as well makes crash cooling very simple, set and forget the STC maxi + freezer working together or just maxi or just freezer.

BUT as I`ve mentioned the Maxi 110 has a very small tank on it so getting to cooling / heating temps doesn't take very long.

[darkonnis]

I'd say add heating. As fermentation tails off it won't provide its own heat if you overcool, nor will you be able to innoculate with brett of anything that like after a ferment as it'll be cooling. Further more maturation at a set temperature cannot be regulated unless you intend to be colder than ambient.

Worth considering.

[Fil]

Heating with a cartridge heater it will be..

missed that post barneey.. DUH!! i was thinking of inserting the heater into the waterbath not the elegant rims style heat tube .. managed to knock one up from the spares box , and the sous vede cold box cooker supplied the heater



just need a pump, and to sus out thye 2ndary relays.. Any pump suggestions would be appreciated, and advice about how to prime the hex loop, is it necessary?.

Have you left the square coil as is or have you pulled it out of the single plane to exchange better or is that not a good idea with the thin tube??

Relays.. ive only used small relays with dc switching voltages and the SSRs that come with pids, looking at your pics barneey i guess thats a set of mains voltage switched relays you have there. whats the spec/cost of em? are they clearly labled for idiots like the SSRs

if i were to use SSRs and a dcV powerbrick to supply the switching voltage would i need to mount them on heatsinks ? is it the load that heats them up or the rapid switching that a pid controls??

ive been let down with the drain fitting so for BB1 will be going old school and syphoning out Just plucking up the courage to drill holes in the nice virgin shiny lid


thanks for all the input..

[Fil]

Progress so far.. no stc1000 controller yet so i have wired up in preperation

from fiddling with arduinos i had a 5vdc coil 240v10a relay board, so i have wired in a feed from a plug in 5v dc psu for the time being.. eventually the dc supply will come from a brewing(x pc) psu feeding everything dc..

i probably didnt need to use all 4 relays but it suited my build 1 circuit at a time approach..






so the wires are ready for the stc, live and neutral to power, 2 red wires for the 5v dc switching voltage to feed the heating and cooling relays, the green wire to switch the compressor and pump on for cooling, and the purple wire to switch the pipe heater and pump on for heating,,

i supplied the board with its own ground (-ve) and VCC (+5v) supply.

i assumed the board relays were numbered 1-4 from left to right with the switching connections to the front?? i will just have to see what turns on when to confirm that now to drill holes in the nice virgin lid for the coil

[Fil]

And the lid coil in not tightened up yet just finger tight..
om begining to doubt the bargain ebay SS swaglock fittings are 10mm as the ferruls? (ss olives) are very loose on the coil tube





i was hopeing i could stretch 3/8" beerline over the ends of 10mm copper to form the transport tube as its a bit more flexible than copper and will fit inside the armoflex tube i have ready. but thats not happening ;(

[barneey]

Fil,

Correct me if I`m wrong but the 10mm swags wont be a good fit for the coil which is going to be 9.5mm so however much tightening you do it will still leak. I wouldn't trust it myself to keep a seal.

[Fil]

your right.. the coil was sold as 10mm and didnt think to check it..DUH!!

So back to the drawing board.. hmm i do have some thin walled 10mm ss tube which will slip onto the 3/8" tube with a lil coaxing so i will fudge a spacer and seal with lsx for the time being

[barneey]

Would these be a better bet?

http://www.ebay.co.uk/itm/Swagelok-SS-6 ... 1193131634?

[Fil]

Would these be a better bet?

http://www.ebay.co.uk/itm/Swagelok-SS-6 ... 1193131634?

possibly if i hadnt already drilled 20mm holes to accommodate 1/2" bsp fittings And wasnt planning on getting a brew underway tomorrow...

so..



i cut 2 short lengths of 10mm .2-.2.5mm walled ss tube, dabed a smear of lsx inside, and started to twist it onto the 3/8" tube, then hit it with an amma



job done!! with only a small amount of blood let, that thin walled tube is SHARP!

as the join is gonna be well above the beer fingers crossed and i will ensure those ends get a boil before use too. now to find the bargain swaglock fittings are 10.2mm..

[barneey]

Good luck with them, will you swap them out after this brew? I would be worried about anything travelling between the two tubes.

[Fil]

coil in blow tight and cleaned,

not perfect.. as its not sealed tight against the lid on one side, and in order to remove to fit more packing washers i will need to destroy a fitting so it will do for an unpressureised fermentation but the tubes in n out are tight so its good enouigh/



all the other pots cleaned after greasy hands fixing bits in and ready to go

[Fil]

Good luck with them, will you swap them out after this brew? I would be worried about anything travelling between the two tubes.

as i hope to try low pressure fermentation at upto 4-5psi yes i will revisit this as i will need to seal the fittings to the lid properly.

i may need to open up the top surface holes a bit more too to allow easier fitting