Ask Mr. Wizard

Equipping a kegerator with gas on the outside


Mike Visser • Santa Rosa, California asks,

 I have a kegerator with two taps on top. Inside I can easily fit two Cornelius kegs plus a 5-pound CO2 cylinder. However, I recently started nitrogenating some of my beers, which requires another cylinder (slightly larger than the CO2 cylinder). I also sometimes have three kegs of beer that I want to refrigerate, or perhaps two kegs and a carboy in secondary fermentation. I would like to drill a couple of holes in the side of my kegerator so that I can keep the gas cylinders outside the kegerator, leaving more space for beer inside. My wife is concerned that the kegerator will leak cold air, and thus increase our electricity consumption. What is the best way to accomplish this while satisfying my wife’s concerns?




There is something about homebrewing that seems to result in debates about the home. The most frequent seems to involve brewers commandeering the kitchen and leaving it a wreck. This, however, is the first dispute over BTUs and homebrewing that I have been sent for comment. This general topic is very fresh in my mind and later in this issue’s column I discuss some of the talks given at the recent Craft Brewers Convention held in San Diego from April 16 to April 19.

Your wife has a valid concern since refrigerators contribute significantly to the monthly energy bill. Older refrigerators cost between $15 and $20 a month to operate, depending on local utility costs and how much heat load is put on the compressor. Heat load increases when you place warm items in the refrigerator or when you allow warm air to enter by either opening the door or by allowing it to enter through cracks in the seal or in your case holes around carbon dioxide lines.

The good news is that this is a really easy problem to properly address by choosing an appropriate installation method. One method is to drill a hole in the side of your kegerator with a hole saw and then cram a flexible hose with a slightly larger diameter than the hole into the side of the cooler. The hose will seal up the hole and air leaks will be kept to a minimum. Another method is to insert a rigid pipe through the hole and attach the gas hose to either end of the pipe. Some people prefer rigid pipe to hose because the hose can wear if wiggled around and the installation can appear messy, but with the pipe you have a decent conductor connecting the inside of the fridge to the ambient air temperature. If you choose pipe over hose you can insulate the pipe and this problem is solved.

We have a fairly large keg cooler we take to beer festivals and it has a single hose supplying carbon dioxide to a small valve block that is screwed to the inside wall. The valve block has little ball valves with hose barbs attached to them and makes it easy to turn the gas on and off to taps as needed. It also eliminates multiple hoses running into the side of the cooler, thereby reducing potential energy loss to the environment and making for a tidier installation.

This seems like a red herring argument. I don’t think your wife is real thrilled about having your kegerator with some ugly carbon dioxide bottle sitting next to it messing up the house. Perhaps a more elegant design and a special brew for your wife will quell her objections to your kegerator improvement project.

Response by Ashton Lewis.