The design of my chiller needs to fit the peculiar requirements of my kit so there are some aspects that would not be of interest and just be an over-complication. But I’ll describe the steps I took for my application and hope there might be something that will help you make yours.
I used a 5 metre length of 10mm diameter copper pipe* (available at Wickes, Screwfix and other DIY suppliers), a 6 metre length of 1.2mm diameter copper wire (available from eBay sellers), a 4 metre length of 14mm ID radiator hose* (available from eBay sellers). I used mostly endfeed copper fittings and 15mm copper pipe for making the various connections for the chiller.
*Some people use 8mm diameter copper pipe. Some people use silicone pipe (more expensive) others use braided PVC hose pipe (less expensive).
I started by making three sub-assemblies, i.e. two “T” connectors for the ends of the chiller and a camlock connector for the chiller hot wort input.
The “T” connectors consisted of one 15mm endfeed copper T fitting with a short length of 15mm pipe soldered into each opening. A 15mm to 10mm reducer is soldered to one of the ends at the top of the T. A 1/2” male BSP to 15mm endfeed is soldered to the bottom of the T. The remaining end is for attaching the radiator hose.
Having made the sub-assemblies the 10mm fitting needs to be drilled and filed out to enable the 10mm copper pipe to pass all the way through.
The third sub-assembly consists of a short length of 15mm copper pipe soldered to a 15mm to 10mm reducer at one end and at the other a 1/2” female BSP to 15mm adaptor. A camlock fitting will be fitted to the BSP fitting later.
Now the fun bit, the chiller coil. The 10mm copper pipe is supplied as a coil about 400mm diameter. The copper wire is also supplied as a coil. The first job to be done is coil the copper wire around the outside of the 10mm copper pipe, soldering it in place at intervals and thread this through the outer, radiator hose.
I approached this by first laying the radiator hose out in a straight(ish) line across my back lawn. I found the best way to straighten the coil of 10mm copper pipe was to hold the free end of the coil against a flat surface, in my case my patio, and unrolling the coil. I did a metre or two at a time. I then threaded the straightened pipe through the coil of copper wire. I then wrapped the wire around the pipe starting about 150-200mm from the end. Solder the wire in place, then continue to wrap the wire around the pipe in a loose spiral (about one turn per 50mm). I soldered the wire to the pipe at about 600mm intervals.
Having established the wire coil I went back to the start and trimmed the wire back to the solder joint and filed it smooth to avoid it catching on the hose as it was inserted.
Before starting to thread the copper pipe through the hose I poured a solution of washing up liquid and hot water down the hose from the far end. I then introduced the first length of pipe into the hose then straightened another metre or so of the coiled pipe, coiled and soldered the wire in position then inserted it further into the hose. This was repeated until the copper pipe appeared out of the far end of the hose. The last coil of wire can be soldered in place so the first and last solder joint are level(ish) with the ends of the radiator hose. The wire was trimmed flush to the last solder joint and filed smooth.
At this point a jubilee clip is threaded on to the hose and one of the T sub-assemblies was threaded on to the far end of the copper pipe and pushed on until the start of the wire coil reached into the sub-assembly.
The sub-assembly was soldered to the 10mm pipe. The 10mm pipe was trimmed to length so the camlock sub-assembly could be soldered in position. The hose was then threaded onto the sub-assembly and fixed in position with the jubilee clip.
Time to coil. For my particular application I wanted the coil to be quite high (long) so opted for a 110mm soil pipe as both a former and a support. The size of the former is optional.
In order to make the job a bit easier, rather than do the coiling at ground level I used a couple of old scaffold planks sat on some old fence posts to raise the coiling surface so the T piece assembly cleared the ground as the coil was produced.
With the T piece positioned so it was flat on the scaffold plank, the soil pipe was laid across the hose, just behind the jubilee clip, and the first half a turn was made. I then drilled a couple of holes either side of the hose, sufficient for a wire wrap, and secured the hose to the soil pipe former.
The coil was then produced by rolling the former along the hose to the end.
The excess 10mm pipe was trimmed to length, a jubilee clip (VERY IMPORTANT) is threaded on to the hose and the second T sub-assembly put into position, threading it on to the hose. The T sub-assembly was soldered into position and the hose secured with the jubilee clip.
(N.B. For my particular application I wanted this connection at the top so cut the cable tie and reversed the coil on the former and retied.)
For my particular application I then spaced the coils out over the length of the former and secured each coil in position using a 25mm conduit clamp and M6 screws and nut.
Having produced the chiller I then turned my attention to how it was to be used. (This is where you might want to stop reading if all you want is a counterflow chiller).
My individual pieces of brewery kit are mounted on castors for ease of storage and setting up. So I needed a base board. I used a square piece of 19mm plywood. Using a hole saw I drilled three holes at an angle at the centre of the base. A short length (~200mm) of soil pipe was positioned at the centre of the base board over the holes and the interior filled with expanding foam.
As a “belts and braces” precaution a disc of plywood was cut to fit the soil pipe and secured in position using M8 stud, washers and nuts.
After priming and painting the base board, the castors were fitted and the chiller assembly fitted onto the base. I made a last minute decision to move the cold water connections to the base that meant fitting a couple of brackets to the base with wall plate elbows. A length of 15mm copper pipe was fitted between the 1/2” BSP connectors and the wall plate connectors on the base. Hoselock connectors were fitted to the wall plate connectors. One unforeseen consequence of this last minute change meant that the water wouldn’t drain from the chiller due to the inverted U configuration of the chiller creating an air lock. A quick mod was required to fit an air vent at the top of the cold water pipe feeding the chiller.
First test run cooled 25 litres of boiling water down to 20C in 20 minutes! Yes, the water supply was very cold but still much better than my immersion chiller performance.
I used a 5 metre length of 10mm diameter copper pipe* (available at Wickes, Screwfix and other DIY suppliers), a 6 metre length of 1.2mm diameter copper wire (available from eBay sellers), a 4 metre length of 14mm ID radiator hose* (available from eBay sellers). I used mostly endfeed copper fittings and 15mm copper pipe for making the various connections for the chiller.
*Some people use 8mm diameter copper pipe. Some people use silicone pipe (more expensive) others use braided PVC hose pipe (less expensive).
I started by making three sub-assemblies, i.e. two “T” connectors for the ends of the chiller and a camlock connector for the chiller hot wort input.
The “T” connectors consisted of one 15mm endfeed copper T fitting with a short length of 15mm pipe soldered into each opening. A 15mm to 10mm reducer is soldered to one of the ends at the top of the T. A 1/2” male BSP to 15mm endfeed is soldered to the bottom of the T. The remaining end is for attaching the radiator hose.
Having made the sub-assemblies the 10mm fitting needs to be drilled and filed out to enable the 10mm copper pipe to pass all the way through.
The third sub-assembly consists of a short length of 15mm copper pipe soldered to a 15mm to 10mm reducer at one end and at the other a 1/2” female BSP to 15mm adaptor. A camlock fitting will be fitted to the BSP fitting later.
Now the fun bit, the chiller coil. The 10mm copper pipe is supplied as a coil about 400mm diameter. The copper wire is also supplied as a coil. The first job to be done is coil the copper wire around the outside of the 10mm copper pipe, soldering it in place at intervals and thread this through the outer, radiator hose.
I approached this by first laying the radiator hose out in a straight(ish) line across my back lawn. I found the best way to straighten the coil of 10mm copper pipe was to hold the free end of the coil against a flat surface, in my case my patio, and unrolling the coil. I did a metre or two at a time. I then threaded the straightened pipe through the coil of copper wire. I then wrapped the wire around the pipe starting about 150-200mm from the end. Solder the wire in place, then continue to wrap the wire around the pipe in a loose spiral (about one turn per 50mm). I soldered the wire to the pipe at about 600mm intervals.
Having established the wire coil I went back to the start and trimmed the wire back to the solder joint and filed it smooth to avoid it catching on the hose as it was inserted.
Before starting to thread the copper pipe through the hose I poured a solution of washing up liquid and hot water down the hose from the far end. I then introduced the first length of pipe into the hose then straightened another metre or so of the coiled pipe, coiled and soldered the wire in position then inserted it further into the hose. This was repeated until the copper pipe appeared out of the far end of the hose. The last coil of wire can be soldered in place so the first and last solder joint are level(ish) with the ends of the radiator hose. The wire was trimmed flush to the last solder joint and filed smooth.
At this point a jubilee clip is threaded on to the hose and one of the T sub-assemblies was threaded on to the far end of the copper pipe and pushed on until the start of the wire coil reached into the sub-assembly.
The sub-assembly was soldered to the 10mm pipe. The 10mm pipe was trimmed to length so the camlock sub-assembly could be soldered in position. The hose was then threaded onto the sub-assembly and fixed in position with the jubilee clip.
Time to coil. For my particular application I wanted the coil to be quite high (long) so opted for a 110mm soil pipe as both a former and a support. The size of the former is optional.
In order to make the job a bit easier, rather than do the coiling at ground level I used a couple of old scaffold planks sat on some old fence posts to raise the coiling surface so the T piece assembly cleared the ground as the coil was produced.
With the T piece positioned so it was flat on the scaffold plank, the soil pipe was laid across the hose, just behind the jubilee clip, and the first half a turn was made. I then drilled a couple of holes either side of the hose, sufficient for a wire wrap, and secured the hose to the soil pipe former.
The coil was then produced by rolling the former along the hose to the end.
The excess 10mm pipe was trimmed to length, a jubilee clip (VERY IMPORTANT) is threaded on to the hose and the second T sub-assembly put into position, threading it on to the hose. The T sub-assembly was soldered into position and the hose secured with the jubilee clip.
(N.B. For my particular application I wanted this connection at the top so cut the cable tie and reversed the coil on the former and retied.)
For my particular application I then spaced the coils out over the length of the former and secured each coil in position using a 25mm conduit clamp and M6 screws and nut.
Having produced the chiller I then turned my attention to how it was to be used. (This is where you might want to stop reading if all you want is a counterflow chiller).
My individual pieces of brewery kit are mounted on castors for ease of storage and setting up. So I needed a base board. I used a square piece of 19mm plywood. Using a hole saw I drilled three holes at an angle at the centre of the base. A short length (~200mm) of soil pipe was positioned at the centre of the base board over the holes and the interior filled with expanding foam.
As a “belts and braces” precaution a disc of plywood was cut to fit the soil pipe and secured in position using M8 stud, washers and nuts.
After priming and painting the base board, the castors were fitted and the chiller assembly fitted onto the base. I made a last minute decision to move the cold water connections to the base that meant fitting a couple of brackets to the base with wall plate elbows. A length of 15mm copper pipe was fitted between the 1/2” BSP connectors and the wall plate connectors on the base. Hoselock connectors were fitted to the wall plate connectors. One unforeseen consequence of this last minute change meant that the water wouldn’t drain from the chiller due to the inverted U configuration of the chiller creating an air lock. A quick mod was required to fit an air vent at the top of the cold water pipe feeding the chiller.
First test run cooled 25 litres of boiling water down to 20C in 20 minutes! Yes, the water supply was very cold but still much better than my immersion chiller performance.
