Converting an Immersion chiller to a Counter-Flow Chiller

Building a Counter Flow Chiller

This work instruction document may be used at your own risk to construct a counter flow chiller from scratch, or converting an immersion chiller to a counter-flow chiller using basic workshop tools. One advantage of a counter flow chiller over an immersion chiller is that the hose water will not come in contact with the wort as sometimes happens with a leaky immersion chiller.  You’re on your own.

Materials

• Cooling Tube, Copper, straightened, smaller diameter than Nipple ID (or straightened immersion chiller to be converted)
• (1) 25’ (8m) Water hose without fittings (Length of the cooling tube determines the length)
• (1) 1.5’ (.5m) Water hose with male fitting
• (1) 1.5’ (.5m) Water hose with female fitting
• (6) Nipples, 2” (50mm) length copper tubes (must be able to fit inside ID of hose)
• (2) Tee fittings, copper, female openings, to fit Nipples
• (2) Reducers. Copper, to transition from Nipple OD to Cooling Tube OD
• (6) Hose Clamps, to compress Hose ends onto Nipples
• Solder
• Solder Flux
• Plastic zip ties as needed, about 8” long
• Tools Required
• Sharp knife
• Wooden Dowel, 2” (50mm), approximately the diameter of the Reducer small end OD
• Sandpaper, for roughing up the solder joint surfaces
• Round file small enough to fit into small end of the Reducer
• (2) metal C-Clamps, about as large as your hand
• Needle Nosed Pliers
• Channel Locks
• Clean shop rags
• Clean Paint Brush (Optional, for cooling soldered joints)
• Hand held Propane tank and valve / nozzle
• Bucket
• Soapy Warm Water
• Clean water from spigot as needed
• Socket wrench and socket to fit the hose clamp fastener
• Soda pop keg to use as a mandrel about which to coil the finished assembly
• Preparations
• Clean and dry the copper components;
• Sand and then tin the surfaces to be soldered

Figure 1 – TINNING THE SURFACES: X = EXTERNAL SURFACES; Y = INTERNAL SURFACES

• Uncoil chiller tube, relatively straight;
• Using the round file, open the small ends of the reducer until it fits easily over the chiller tube;
• Directions, Assembling the Adapters
• Make a pilot from the wooden dowel with the knife with a pilot that fits snuggly into the ID of the reducer’s small end, and a major diameter as large or larger than the OD of the small end;

Figure 2 - PILOT FOR INSTALLING HOSE

• Place the torch upright on the work surface and set it alight; This frees both hands;
• Assemble the adapter, starting by holding the Tee with the channel locks and adding the nipples one at a time, starting with the middle connection;
• Clamp a C-Clamp onto the middle joint to act as a heat sink to prevent it coming un-soldered whilst making the other two joints;
• Dampen the clean cloth, cool the joint once it is soldered; or use the paintbrush loaded with water as an optional method;
• Finish by adding the reducer.

Figure 3 - ASSEMBLED ADAPTER; (2) REQUIRED

NOTE: BEFORE YOU SOLDER THE OTHER ADAPTER ONTO OTHER END: do so ONLY on one end.

• Slide an adapter assembly over one end of the Chiller Tube;
• Note the area where the reducer and the Chiller Tube contact one another;
• Remove the adapter and tin the area of the tube;
• Replace the adapter and attach the C-Clamp to the large end of the reducer; this will draw heat away from the joint that has already been soldered on the adapter;
• Heat the chiller tube and the reducer, and solder the joint.
• Cool with the damp cloth or the optional soaked paintbrush

BEFORE YOU SOLDER THE OTHER ADAPTER ON THE OTHER END!!! Do the Following:

Directions, Adding the Long Hose

• Coil the hose in the bucked and add the warm soapy water; (You really want to do this)
• Insert the pilot into the Chiller Tube; (You really want to do this too)
• Place two of the Hose Clamps onto the end of the Hose; (You DEFINATELY want to do this)
• Feed the hose over the Tube and force it over the end of the nipple on the adapter;
• Position the Hose Clamps onto the hose in the area of the nipple, and tighten them both with the socket wrench;
• Locate the other end of the Chiller Tube by feel through the hose;
• Cut the hose off at a desired position that will leave enough of the chiller tube exposed to add the other adapter;
• Remove, and discard the pilot- unless you need it for another build.

Directions for Adding the second adapter

• Slide the other adapter over the chiller tube;
• Place two of the Hose Clamps onto the end of the Hose;
• Note where the Reducer and the Chiller Tube will make contact;
• Remove the adapter and tin that area of the chiller tube;
• Replace the adapter on the chiller tube;
• PULL THE HOSE BACK in the direction of the other end, and use the C-Clamp to keep it out of the way. This will keep the hose as far from the heat as possible;
• Locate the adapter in position for soldering;
• Clamp the other C-Clamp onto the large end joint of the reducer to act as a heat sink;
• Solder the small end of the reducer to the tinned area of the Chiller Tube;
• Cool the joint with the damp cloth or the soaked paintbrush;
• Remove both C-Clamps;
• Force the hose over the adapter Nipple;
• Locate the two Hose Clamps and tighten with the Socket Wrench.
• Directions to add the short hoses;
• Place the remaining Hose Clamps over the ends of the 1.5’ (.5m) hoses;
• Force the hoses over the Adapter Nipples;
• Locate the two Hose Clamps and tighten with the Socket Wrench.

Directions to Pressure Test the solder joints (May be done before or after coiling the final assembly)

• Connect the female end of the assembly to the spigot;
• Turn the water on as much as it will be when used to chill;
• On the Male connection of the hose, block the stream and take note of any leaks;
• If no leaks, go on to the Coiling portion of the show;
• If there are leaks, fix them, using the C-Clamps as heat sinks to prevent loosening other solder joints and to prevent burning the hose. (Use this method to rotate the adapters in the final assembly to orientations that best serve your purposes.)

Directions for Coiling the finished assembly

• Zip tie one end of the assembly to the handle of the Keg;
• Place a Zip Tie under the hose;
• Wrap the hose around the Keg;
• When the wrap comes to the Zip Tie, zip the coils together;
• Continue until the assembly is wrapped into a coil;
• Remove the tie that bound the end of the coil to the keg handle;
• Remove the coil from the keg;
• Use more Zip Ties to bind together adjacent coils at one or two more locations around the coil;
• Clip the stray ends of the zip ties;
• Sanitize the inside of the chiller tube.

Figure 4 - COUNTER FLOW CHILLER ASSEMBLY, WATER SOURCE (BOTTOM) AND WASTE WATER (TOP) HOSES NOT SHOWN

Go brew beer.

• Put the Female End of the Counter Flow Chiller Jacket ON the bottom;
• Connect the water supply to the bottom;
• Connect a hose to the top to remove the heated water to another location.
• Connect the top end of the Counter Flow Chiller Tube to the hot wort drain;
• Connect the bottom end of the Counter Flow Chiller Tube to the tube leading into the Carboy.

Notes

I place a valve on the egress side of the water jacket to regulate the water flow, and thus, regulate the temperature of the wort exiting the chiller tube; By doing this I will not have to adjust the water flow at the spigot end of the water supply hose to achieve the temperature that I desire.

Cheers!