Build a Keg Washer

If you’re like me and you own more than four corny kegs (I own 26), then cleaning them by hand is a real drag. After working in a professional brewery for years and seeing the beauty and convenience of a keg washing system, I decided to build my own. Most homebrewers start with a submersible pump in a bucket with a perforated pipe coming up from it to spray cleaning solution into the keg. I built a crude version of this and was disappointed in the results.

My pump kept going into thermal shutdown (I like my PBW hot) and then started leaking oil. It was time to up my cleaning game.

The system I designed accomplishes rinsing, cleaning, and re-rinsing of kegs with minimal changing of hoses. When the cleaning and rinsing cycles are finished, the kegs are ready to be broken down and sanitized.

To achieve this the system uses a re-purposed keg as the cleaning solution vessel (CSV). It is outfitted with a drain in the bottom (I used a stainless steel bar sink drain from the hardware store for a weldless solution), an electric element to keep the solution hot, and a temperature probe for the element’s controller. The heating element shouldn’t be left out of this project as effective CIP cleaning (in a reasonable amount of time) requires a hot cleaning solution. The top of the keg is cut to support the handles of a corny keg, with notches for clearance of the port cleaning hoses.

The pump I used is an AMT 429B-98. This is a 3⁄4 horsepower pump with a stainless head. Its seals are chemical resistant and it is rated for fluids up to 200 °F (93 °C). These pumps are usually cost-prohibitive for homebrewers, but I found a new one on eBay for under $200. You don’t have to buy this exact pump to build a great CIP system, but I would recommend something with at least 1⁄2 HP and the above-mentioned properties for safe, effective cleaning.

Cleaning solution is pumped from the CSV and up through a stainless spray ball that sits inside the inverted corny keg. The solution drains out of the keg and back into the cleaning solution vessel. There is a 1⁄2 in. (13 mm) port on the 90° elbow above the pump that allows the cleaner to flow through a check valve and into the two hoses that connect to the liquid and gas ports of the corny keg.

When washing is complete, the port cleaning hoses stay connected to the ports. The corny keg is removed from atop the cleaning vessel and placed on the rinsing wand. The rinsing wand (a vertical copper pipe drilled with a series of 1⁄8-inch/3-mm holes) and its plumbing are all made of potable water rated components (CPVC and copper). When the rinse water valve is opened, cold tap water flows to the rinsing wand and through a tee and a check valve to the port cleaning hoses. The check valve on the cleaning side prevents rinse water from entering the cleaning loop, just as the check valve on the rinse side prevents cleaning solution from entering the rinse apparatus. Once the keg has been sufficiently rinsed, it is ready to be broken down and sanitized.

To put the unit into storage I disconnect power from the pump and heating element and open the dump valve (see photo). When the cleaning solution has emptied I close the dump valve and then hook a fresh tap water hose to the feed side of the pump and close the valve below the vessel. This forces the rinse water up through the pump and the spray ball. It’s handy to have a spare corny keg sitting on the unit for this so you don’t get soaked! Finally, I re-open the dump valve and open the valve directly below the CSV and give it a good hand rinsing.

Since your pump may vary from mine, the materials list is approximate. Pick out the fittings that suit your needs to accomplish the same functions as my machine.

This is an advanced project that should only be attempted by those familiar with plumbing and wiring. If any parts of this project are assembled improperly you risk failure of key components, injury, electrocution, and making a gigantic mess.

 BUILD YOUR OWN CIP SYSTEM