Archive for the 'Homebrewing' Category

How not to build a kegerator

We’re planning a bar renovation, and I wanted to take the opportunity to build in an ultimate homebrew draft system.

The heart of this new draft system is to be a Danby DWC2727BLS.  The DBC2760BLS appears to be effectively identical, with a slightly different arrangement of internal shelves.  This is a “french door” wine/beverage centre.  The really unique feature of this unit is that the two doors open onto separate compartments, each of which can be programmed to a different temperature.  Each of the two compartments is just barely big enough to squeeze in a 5 gallon homebrew “Corny” keg, without any modification at all.

Combined with a dual-regulator CO2 system, this would allow serving two different beers, each at its own ideal temperature and pressure.  A cellar-temperature low-carbonation English ale on one side, and a sparkling cold frosty lager on the other.

I bought the fridge at a good “scratch’n’dent” price.  It was actually just the cardboard carton that was somewhat banged up.  The fridge inside was in perfect condition.

I started the required modifications today.  It has not gone well:

A $600 hissing noise

What the hell is that?  Some kind of tube?

That would explain the hissing sound when I stopped the hole-saw.  Not burning insulation, as I thought at first.  That’s really heart-breaking.

For anyone else looking to modify a Danby DWC2727BLS, that tube runs side-to-side, about 12-1/4″ inches from the back of the fridge.  At least that’s where it is on mine.  Maybe not always in the same place.

How could this have been avoided?

Manufacturer cooperation

When I was building my earlier Danby-based kegerator, I actually called Danby to inquire about the locations of any important plumbing.  I got nothing out of them.  They wouldn’t tell me.  So, I didn’t bother trying this time.

Perhaps they don’t want to encourage people to modify their products.  Perhaps they think that people modifying their products are more likely to accidentally release refrigerant into the atmosphere.  Perhaps they think that by cooperating with modifiers, they would be contributing to the release of refrigerant into the atmosphere.

I would argue that it’s only uninformed people that will accidentally release refrigerant.  These modifications are not difficult; anybody with some decent tools and a modicum of skill could accomplish them… given the required information.  By not providing that information, they contribute to the release of refrigerant.  What happened today proves the point.

Reading this guy’s web-page

I wish I had stumbled across this other kegerator-conversion page, for building a Sanyo-based kegerator.

This guy’s steps are mostly the same as I used on my earlier Danby conversion.  But he adds one really great technique I wish I had thought of: using an alcohol/cornstarch mixture to detect the locations of refrigerant lines.

Use a nibbling tool, not a hole saw

On my previous kegerator conversion, I used a nibbling tool to cut out the hole.  I didn’t have any hole-saws of that size at the time.  This time, I used a big hole saw.  The nibbler always gives me a blister, and I didn’t want that.  But the hole saw is a Bad Idea.  The hole saw will cut through anything vital before you know it’s there.

With a nibbling tool, you’re only at real risk drilling the first pilot hole, which is small.  After that, as you nibble around the big hole with the nibbler, you will immediately notice if you hit anything like a refrigerant tube, before doing any damage.

What now?

Tomorrow I will call some appliance repair specialists, see if it’s possible to repair the tube and recharge the system with new refrigerant.  I’m doubtful, though.  I believe this tube was the “capillary tube”, which runs between the condensor and the evaporator.  The specific length and dimensions of the capillary tube are carefully tuned to provide just the right amount of restriction.  Splicing in a repair might mess that up.

Also, it’s possible little particles of metal could have got into the tube, and may mess up the compressor.  The system is currently open to the atmosphere, and allowing water vapour in.  I tried to plug up the ends of the tube with bits of electrical tape as best I could, but it still may require a careful purging with dry nitrogen and a new filter/drier.

All-in-all, repair might be very expensive, if even possible.

I could also just trash this whole unit, and try again.  But I doubt I’ll find another scratch’n’dent bargain at $600.  I may have to pay the full price, over $1000.

A painful lesson.

Lazy “homebrewing”

I don’t really have nearly as much time for brewing as I would like.  So, my kegerator tends to go long periods with no beer in it.

Until now.

If you have a kegerator, but no time for brewing, and happen to live in the Southwestern Ontario area, then take up thy Corny keg and hie thee hence to Grand River Brewing in Cambridge.  They’ll fill up your keg with 5 gallons of your choice of professionally-made craft beer.

I’ve only had their Hannenberg Pils so far.  It’s quite fine, and definitely the fastest and easiest “homebrew” I’ve ever “made”.

Pneumatic pinch valve, 1/2″ version

After successful testing of my prototype pneumatic pinch valve with a 3/8″ bore, I proceeded to design an improved version with a full 1/2″ bore. This version uses silicone tubing instead of latex, which I believe will not contribute any off-flavours, and will not break down eventually as latex tubing is prone to do. In addition, it also has pipe-thread connections for inlet and outlet so it can be plumbed into a system easily, but can be removed if necessary.

See my page here on how it was constructed.

Pneumatic pinch valve

In a previous post, I wrote about an experiment at building a solenoid pinch-valve, as an inexpensive alternative to the exorbitantly-priced solenoid valves commonly used in automated homebrewing systems. That attempt was a failure, not even able to seal against 5psi pressure.

I have since attempted another approach: a pneumatic pinch valve. The idea here is that the fluid is carried through a length of flexible tubing, and that flexible tubing is run through a rigid jacket that can be pressurized with air (or another gas or fluid). If the control pressure is high enough, it will squeeze the flexible tubing shut, and pinch off the flow of the fluid.

Continue reading ‘Pneumatic pinch valve’

Homebrewing pages updated

I’ve done some more work on my brewing gear, updated a few of my old construction pages, and added a couple new ones.

Converted more kegs into brewing vessels. I used a new welding company, Grand Valley Specialty Welding, who did much nicer work than the last guy. Also added a glass sight gauge to the hot liquor tank.

Updated pages:

New pages: