Low profile (<1/2") blow off tube for Fermonster 7 gallon big mouth carboy in a fermentation chamber.

[brewman !]

I bought an Igloo Frw482c wine fridge to use as a fermentation chamber. It holds a 7 gallon Fermonster without modification but there is less than 1/2" clearance between the lid and the ceiling of the fridge.

How do I make a really low profile blow off tube for this setup ? 2 pieces of 3/8" hose ?

I need something that will handle blowoffs like this...

Thanks

 

[VikeMan]

Wait... less than 1/2" between the lid and the ceiling of the fridge? Do you mean less than 1/2" between the top of the airlock and the ceiling of the fridge? Just want to make sure we understand the baseline here.

 

[brewman !]

Wait... less than 1/2" between the lid and the ceiling of the fridge? Do you mean less than 1/2" between the top of the airlock and the ceiling of the fridge? Just want to make sure we understand the baseline here.

Yes, 1/2" between the top of an undrilled lid and the ceiling of the fridge. No airlock.

So I'll need to use a blowoff tube of some sort and a jar that acts as the air lock. Unless I drill a hole in the top of the fridge for the airlock to stick out of ? Are there freon tubes in the top side of a beverage cooler ?

There is quite a bit of space between the top of the compressor and the underside of the hump. I could probably lower the hump by an inch or so if I did major surgery. I'd rather not though.

I'll take a picture of the setup tomorrow and post it here.

 

[IslandLizard]

I need something that will handle blowoffs like this...

The first step would be to fill the Fermonster with less beer, leaving 1-1.5 gallon of headspace.

there is less than 1/2" clearance between the lid and the ceiling of the fridge.

If there is indeed that little space, perhaps stick a plastic elbow into the airlock hole, and fasten a piece of tubing to the exit side of the elbow. 1/2" is very tight, though.

 

[Knightshade]

+1 on @IslandLizard 's point on less beer in the Fermonster. That is well over 5.5G I do know that by looking at it. (I've got 2 of the same size)

Get a solid lid and do something like the attached?

Or..punch out the hole on your existing rubber bung and shove a tube into that.

The fermonster will also stand up to putting something on the body of it (at least short term?) if vertical space continues to be an issue. I don't quite remember why I came across this a couple of years ago but..

https://github.com/CommonGarden/Fermenter
You'd still need to put less in there though..maybe some Fermcap would help as well?

 

[brewman !]

@Knightshade The setup in the attached image would work great. Where did you find it ?

It turns out that fitting is used with the Brewjacket Immersion Pro chilling system.

https://www.homebrewwest.ie/brewjacket-adjusted-lid-for-fermonster-7792-p.asp
Where can I buy that elbow by itself ?

Found something similar on eBay.
https://www.ebay.com/itm/154654981056
https://www.ebay.com/itm/224981292885
AliExpress has them:
https://www.aliexpress.com/item/1005001425211785.html
3/8" ID hose should be big enough ?

 

[IslandLizard]

Where can I buy that elbow by itself ?

You can probably and hopefully find something suitable in your local hardware/plumbing store. Since that top space is very, very tight (1/2" you said) I'd make/bend something in a slight U-ish shape from thin walled copper tubing, that extends a bit (a couple inches) past the lid/fermonster to connect your blow-off tubing to. You cannot connect tubing to a regular elbow in that 1/2" space anyway.*

I say locally, since that tube needs to be customized a bit. Also far quicker than have it delivered somewhere in February, coming on the slow-boat from China (Ali-X).

* You'd would want at least 3/8"-1/2" ID on your blow-off tubing/adapters, 1/2" ID preferred.
If using anything with 3/8" ID you surely need to keep checking very periodically for any signs of blockage. Anything narrower can/will clog too easily, especially when the tubing is long... ==> Boom!

I know that space is tight, but using 1/4" ID or less is very risky.

 

[Whisky River]

I have made a few attempts at a similar solution and I was never able to get a tight enough bend to keep the discharge tube as low to the lid as you might need in your situation, so I went with the low profile bulkhead elbows instead.
If you are concerned about blockage you might consider using a few fittings and hoses placed on opposite sides of the lid. It wouldn’t guarantee they won’t all get clogged but it might give you some measure of redundancy.
FWIW I also considered drilling and porting the upper body of the Fermonster, I felt the plastic was thick enough to handle having a fairly large hole drilled and fitting added without loosing it’s integrity, but I was happy enough with the elbow that I haven’t had to try it yet.

 

[Knightshade]

@Knightshade The setup in the attached image would work great. Where did you find it ?

It turns out that fitting is used with the Brewjacket Immersion Pro chilling system.

https://www.homebrewwest.ie/brewjacket-adjusted-lid-for-fermonster-7792-p.asp
Where can I buy that elbow by itself ?

Found something similar on eBay.
https://www.ebay.com/itm/154654981056
https://www.ebay.com/itm/224981292885
AliExpress has them:
https://www.aliexpress.com/item/1005001425211785.html
3/8" ID hose should be big enough ?

I think @IslandLizard gave you your best path to a working solution.

The image w/the elbow in question led to a dead link, which is why it was only a screenshot. It looks generic enough but with some searching around I found this? Anvil Bucket Fermentor Blow-Off Kit

Found some similar stuff here (but I doubt you want to purchase 250 or similar bulk numbers of these things), so perhaps a visit to a local hardware store to peruse their irrigation systems area or a hydroponics store might be in order.

https://hydrobuilder.com/garden-care-pest-control/drip-irrigation/irrigation-fittings.html

 

[Deadalus]

I have a wine fridge setup that is too tight for a 3 pc airlock. I use these SS blowoff tubes Coldbreak makes them, perhaps other companies too. I got 3 for cheap a few years back. They can be pushed into the rubber stopper as far as the start of the bend.

 

[brewman !]

https://www.amazon.com/Homebrewers-Outpost-FE478-Silicone-Solid/dp/B074D9V9QD

 

[IslandLizard]

Amazon.com: Homebrewers Outpost FE478 Silicone Bung (Solid) - Carboy : Home & Kitchen
Buy Homebrewers Outpost FE478 Silicone Bung (Solid) - Carboy: Carboys - Amazon.com ✓ FREE DELIVERY possible on eligible purchases www.amazon.com

Mind, what you linked to is a solid bung, not an "airlock."

However, they do make that flapper "airlock." You still need some space above it for it to be able to lift up and burp.

Please note:
Silicone has a major drawback: It's highly oxygen permeable!
Because oxygen can flow through it easily, over the 2-3 weeks in a fermenter your beer may get oxidized.

While there's active fermentation there's probably enough CO2 production that will drive off most O2 that entered. But as soon as CO2 production slows, O2 will start to build up inside.

In comparison with a regular water filled airlock, or a blow-off tube with the end submerged into a jug with water or Starsan, doesn't allow O2 flowing back in.

 

[VikeMan]

Please note:
Silicone has a major drawback: It's highly oxygen permeable!
Because oxygen can flow through it easily, over the 2-3 weeks in a fermenter your beer may get oxidized.

While there's active fermentation there's probably enough CO2 production that will drive off most O2 that entered. But as soon as CO2 production slows, O2 will start to build up inside.

Word.

In comparison with a regular water filled airlock, or a blow-off tube with the end submerged into a jug with water or Starsan, doesn't allow O2 flowing back in.

Of course airlocks (and blowoffs) also allow O2 to enter, particularly when CO2 has stopped vigorously evolving, but it's a relatively slow slog through the airlock (or blowoff) liquid.

 

[brewman !]

Update

Rather than mess around with the low profile blowoff tube, I sold that fridge and bought a different one.