Maxi Cooler and Fermenters

[stuarts]

looking advice.

Currently I am using 2 Fermentation Fridges and 1 Kegerator which takes alot of space up in my Garage and getting very cluttered. So it got me thinking what can I do to save space?
My thoughts were to look at Maxi 110 Coolers so my question is can I use the recirculation part to control the my 2 fermenters if I get I jackets and Cooling coils . And use the product lines for pouring my kegs.

 

[peebee]

Some of us know little else (I'm not putting my 70 litre fermenter in a 'fridge!). My Maxi 110-like clone will control the temperature of the 70 litre fermenter (wrapped in a few turns of PVC tube) and a 30 litre Grainfather fermenter, at the same time if necessary (I don't use the cooler's "product" cooling coils but do have a small submersible pump in the water-bath to feed the cooling circuit for a second fermenter).

 

[stuarts]

Some of us know little else (I'm not putting my 70 litre fermenter in a 'fridge!). My Maxi 110-like clone will control the temperature of the 70 litre fermenter (wrapped in a few turns of PVC tube) and a 30 litre Grainfather fermenter, at the same time if necessary (I don't use the cooler's "product" cooling coils but do have a small submersible pump in the water-bath to feed the cooling circuit for a second fermenter).

How did you link the 2 fermenters to the recic line? I was hoping to add a pump on each fermenter and plug that into a Inkbird so each can divert the cold water individually

 

[Hazelwood Brewery]

I’ve done the same. I use these pumps because they are very small and can pump the coolant up to 5m (most small submersible pumps struggle to lift much more than 1m). Got mine from Amazon but I have seen them cheaper on EBay and other sites.

Also an update on my shed cooling. The replacement pump was actually too big to sit in the water bath among the cooling coils so I couldn’t use it. I did find another pump and took a punt on it. It has worked a treat and is tiny. The body of the pump is not far off the size of a medium sized egg but can pump water to a head of 5m. It needs a 12v 1A supply so I’ve given it a 5A supply, of course.

View attachment 68980
View attachment 68981

 

[tigertim]

It's either a case of adding multiple submersible pumps to the water bath of the chiller; one for each fermenter, or using one pump and having diverter valve(s) to send the chilled medium to whichever fermenter is calling. Andy (@chopps) of Four Priests Brewery covered the latter topic in his video below. He details the logic of operating the pump when either fermenter calls for cooling, but opening just the valve(s) specific to the fermenter(s). If that makes sense.

It's worth noting that the recirc pump and agitator in these shelf coolers are often combined and this needs to be taken into consideration if planning on using this pump to supply the chlling loop. If the agitator isn't running whilst the chiller is actively cooling, then it runs the risk of the ice bath completely freezing over.

 

[Hazelwood Brewery]

I previously used motorised valves and they became another point of failure. I now have three of those small submersible pumps in my chiller, each switched by an Inkbird (STC-1000) and so far, touch wood, they’ve been very reliable.

 

[Hazelwood Brewery]

Sorry Stuart you had another question about also using the product coils. Yes you can, there’s a “but”…

In the heat of the summer there will come a point where your fermenters may call for cooling frequently and the temperature of your water/ice bath may rise such that the product coils can’t chill the product to the same extent. This probably only matters if you are serving lagers and demand they be at very low temps, even at the height of the summer.

 

[stuarts]

Hazelwood
Thanks for the answer on Product Coils. Being in Scotland it is very rarely I would need extra cold Lager plus personally I don't drink it, and if it was that hot I would only have One keg on draught at a time and/or change to Kveik but over the years I have only lost 1 brew to hot weather
I have alot of thinking to do regards what is the best system for me but I could certainly save space . Wondering if I would save electricity as well running only a Maxi.
Funny how over the years this hobby has got me steadily gathering fridges and kegs then suddenly you think there must be a better way .

 

[Hazelwood Brewery]

Hazelwood
Thanks for the answer on Product Coils. Being in Scotland it is very rarely I would need extra cold Lager plus personally I don't drink it, and if it was that hot I would only have One keg on draught at a time and/or change to Kveik but over the years I have only lost 1 brew to hot weather
I have alot of thinking to do regards what is the best system for me but I could certainly save space . Wondering if I would save electricity as well running only a Maxi.
Funny how over the years this hobby has got me steadily gathering fridges and kegs then suddenly you think there must be a better way .

Yeah, stuff grows organically and before you know it…!

As you’re in Scotland you’re less likely to suffer(?) the higher temperatures to the same extent as me in the South East. Combined with you not needing cold lagers I think you’ll be OK using the submersible pumps and product coils.

 

[peebee]

How did you link the 2 fermenters to the recic line? I was hoping to add a pump on each fermenter and plug that into a Inkbird so each can divert the cold water individually

I think the others have answered that. Otherwise, I did say ...

... but do have a small submersible pump in the water-bath to feed the cooling circuit for a second fermenter ...

I'll probably add a second cooling circuit and do away with using the cooler's circulation circuit. The first add-in cooling circuit has a submersible pump controlled by the built-in Grainfather controller. The Cooler itself is controlled by an Inkbird ITC-308 with the probe in the big fermenter but that's not ideal: The ITC-308s are a defective design (but almost everyone refuses to believe it despite the evidence) so I'll probably put its probe in the Cooler's water bath (I can use a wider, 4-5°C, over temperature trigger to avoid the worse of the defect) and use a more reliable controller to pair with the pump in the cooling second circuit.

Rather than a second circuit I could use a cheap self-priming pump (diaphragm type?) in-line with the existing circulation circuit. Self-priming pumps will seal the circuit when not operating, so the Cooler's pump can't interfere (the pump still "agitates" and its pumping capability, hopelessly weak anyway, won't be overstressed because the pump is an "open-impeller" design ... it still turns but the water goes nowhere).

You can use solenoid activated "diverter valves", but they are expensive and break if you sneeze on them. Little pumps are cheap and a lot more reliable. If you must use diverter valves you can have my broken ones for spare parts.

 

[stuarts]

Thanks for the replies lots to think about. Leaning towards submersible pumps controlled by an ITC 308(As I have them already) in the Maxi water Bath . I have most of the bits and pieces lying about so it would only be the outlay for the Maxi and pumps .
Though Maxi prices seem to be High at present which may mean prevent it for the time being .

 

[stuarts]

I managed to get a Brandels cooler with recirculation pipes and 2 product coils for £50 just needs a good clean, but in working order . So now to work out which way I am going to cool my fermenters.

 

[hoppyscotty]

Hazelwood
Thanks for the answer on Product Coils. Being in Scotland it is very rarely I would need extra cold Lager plus personally I don't drink it, and if it was that hot I would only have One keg on draught at a time and/or change to Kveik but over the years I have only lost 1 brew to hot weather
I have alot of thinking to do regards what is the best system for me but I could certainly save space . Wondering if I would save electricity as well running only a Maxi.
Funny how over the years this hobby has got me steadily gathering fridges and kegs then suddenly you think there must be a better way .

I run 1 fermenter from one Maxi 110 and currently I am using water in the bath and circulating glycol in the product coils. I have connected the product coils in series so the glycol gets two passes and I use glycol to prevent freezing of the liquid once the external pump (controlled by an Inkbird) stops running when cooling is no longer demanded.

It works a treat for ales but in this configuration I do struggle to get the temp down below 3 degrees which might be a problem for lagers. And if you're running more than one fermenter then this configuration wont really suit and then you'd need to move to a configuration that pulls the liquid straight from bath - or from the continually circulating recirc loop and incorporating solenoid switches...which just seems alot more faff.

But whatever you do its a far cheaper solution than a proper glycol cooler and works as well especially if you convert from a water bath to a glycol bath and push the glycol to below zero temps.

However the unit does generate alot of heat...over this hot summer it got chuffing warm in the garage - in the low 30's....alot of the heat build up was from the heat kicked out by the Maxi. I did consider hooking up a fan to an InkBird to turn on once the temp got to the high 20's just to get some air moving and direct it over the maxi radiator, but despite that the temperature of the beer in the fermenter was controlled perfectly fine.

A friend of mine has a similar set up and has a bucket of glycol with a submersible pump pulling the glycol out of the bucket and through the product coils. Takes up less space than having a bucket of glycol in a fridge setup.

 

[stuarts]

Still not sure what way I will use the Cooler. It has 3 product coils and a recirculation coil. Cant seem to work out how to get into the water Bath but from what I can see there is limited space due to the 3 coils.I was hoping to drop pumps into the water Bath but may use an old Coolbox I have full of glycol with submersible pumps pumping thru the products coils then on to the fermenters.

 

[hoppyscotty]

Still not sure what way I will use the Cooler. It has 3 product coils and a recirculation coil. Cant seem to work out how to get into the water Bath but from what I can see there is limited space due to the 3 coils.I was hoping to drop pumps into the water Bath but may use an old Coolbox I have full of glycol with submersible pumps pumping thru the products coils then on to the fermenters.

If you're tapping directly from the water bath you need to remove the product coils. But I think in that case you will need to convert from water to glycol because they work by allowing ice to form around the edge of the bath to provide some thermal buffer and that will take up space and could interfere with the operation of the submersible pumps.

So by using glycol you avoid the freezing and have more space in the bath and have the option of bypassing the thermostat and controlling with an Inkbird so you can run the glycol bath at a lower temperature. The submersible pump you need only needs to be small...its just a circulation pump once you've flooded and purged the lines, so doesn't need to be a powerful pump. They're smaller than a matchbox usually.

 

[Hazelwood Brewery]

Still not sure what way I will use the Cooler. It has 3 product coils and a recirculation coil. Cant seem to work out how to get into the water Bath but from what I can see there is limited space due to the 3 coils.I was hoping to drop pumps into the water Bath but may use an old Coolbox I have full of glycol with submersible pumps pumping thru the products coils then on to the fermenters.

Remove the existing pump, this will give you access to the water bath. Discard the existing pump (or just put it on a shelf and forget it). Use 1 to 3 of the small submersible pumps I mentioned previously.

I use 3. 1 runs permanently and keeps the python cold (also continuously recirculates the coolant in the bath as a consequence). The other 2 are independently controlled by Inkbirds to run 2 coolant circuits - these could be your fermenters.

The above approach then allows you to separately use the product coils, which I didn’t remove, to cool your beer. You’ll enjoy this capability in the summer.

 

[stuarts]

Been playing about this morning and looks like your right about the original pump and access. Was thinking about getting something like this as I don't have any coiling coils yet and have 3 different makes of fermenter would mean I only need to and the 2.
https://www.acask.com/shop/keg-cooling-jackets/keg-wrap-piped-jacket-20-litre-cpk-kk20p/

 

[aolcot]

If you are only running 1 FV, then its pretty straight forward to just use the recirculation ports. I've maxi 310 and I basically I opened mine up and put the recirc pump on a dedicated power supply which the Inkbird provides. This allows the compressor to stay on all the time to build up the ice bath, and the inkbird start/stops the recirc pump when it needs to cool. I can get really low temps with just water

Naturally if you have more than 1 FV, then this isn't going to work unless you have motorised valves, or multiple pumps as mentioned before

 

[Weizenberg]

I use a maxi 110 for my 50l fermenter.

With some propylene glycol i can get the water bath sub-zero which is fine for primary with lagers (6C - 9C - 5C, then into kegerator for a long conditioning phase).

I posted the results in a different thread, but here are some pictures again. Hope they are helpful....

Note that the waterbath and the fermentation temperature are on seperate controllers.

Interrupting the faucet pump with an SSR (as someone suggested earlier on), works rather well.

I would probably opt for another 110 for two fermenters. Im afraid I wont be much help for that particular scenario. You might need a more powerful chiller for that.

 

[aolcot]

You could use an SSR but it can be even easier than that for a single FV with an inkbird:

1. Get a bit of mains cable with a mains plug on one end
2. Take lid off your maxi
3. Drill hole big enough for mains cable in the back of your maxi
4. Feed mains cable through
5. Locate flex feeding recirc pump inside maxi and rewire into the mains cable, leaving the earth attached to the maxi

Now the recirc pump can come on/off when the inkbird calls for it..

see pic where I have a new mains cable coming in (top flex of the two coming in), and wired into the flex of the pump via a choc block