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I’ve run across many reasons for farmer’s decision to invest in aquaponics as I’m sure you have also. It seems as if all share a common interest in preserving Mother Earth and using what she has given us to the best of their abilities. That is where Chillking stands out in our industry. Most that have experience in indoor gardening know our name as the leading name in cooling systems for hydroponics.
We have been building chillers for over twenty years. Our goal is to produce the most economical, environmentally friendly, dependable chiller in the industries we serve. Only Chillking guarantees that our chiller will produce 110% at minimum of the chiller’s nominal tons listing. A ten ton must produce eleven tons at 90F ambient conditions. Many companies boast 100% ratings however they are at 70F ambient or a 90F condenser, not the same thing. Nonetheless Chillking’s chillers exceed their nominal tons rating by a minimum of 10% when tested at 90F ambient. Chillking tests every chiller under load, each chiller is fine tuned to use as little energy as possible. No Chillking chiller is allowed to leave our factory unless it exceeds it’s rating by 10%. In addition to producing 10% more than nominal tons listing we use much less energy while under load. We normally use 15% to 25% less electricity than most of our competitors. When a chiller produces 10% more BTU it is satisfied 10% sooner. Quite often our chillers produce 25% more than their rating.
I’ve gone into depth because we are not the ordinary chiller company. We hold the only patent to yield 100% tank capacity when refueling with hydrocarbons such as methane or compressed natural gas. We are the only authorized Chiller company for International Dairy Queen and Sonic Drive Ins, some of our other customers are Dell, Disney World, International Paper, Rockwell, GE MRI, Hitachi MRI. Airbus is purchasing a 200 ton system from one of our distributors that we will design especially for that application. We have partnered with hydroponic companies building modules for the new MMJ industry in legal states. We worked with the University of Arizona many years ago in designing a system for their agriculture laboratories. In addition we have worked with many other industries.
We are building prototypes that run from solar panels with lower voltage compressors. Our goal is a grid free self-sufficient, stand alone cooling system. We were the first chiller company to recover waste heat from the chiller and repurpose it by storing it for a future need. We have tied our heat recovery system into solar collectors as well. In addition Chillking builds cooling towers and dry coolers however our new chillers have proven more energy efficient than cooling towers so we seldom recommend those. We do have hybrid systems also. The possibilities are endless.
I’ve gone into more depth on this email than I normally would while introducing Chillking. I’ve done so because I feel there is more opportunity for growth as well as being an excellent industry for health and our planet. All companies have an obligation to our planet and consumers. If you feel there are opportunities for your company and Chillking to work hand in hand on projects please contact me. Your company is one of the few companies I am reaching out to in the industry. We would be most happy to design a system especially for your company or offer support.
1 BTU to change 1 pound of water 1F in 1 hour
All calculations are based on that. We first convert GPM to per hour, then get the weight and multiply times the Delta “T” of 20F. The temperature differential of most heat exchangers (HEX or HX) is 20F, meaning in at one temperature and out 20F cooler.
This exercise is to demonstrate the tremendous BTU than be carried by pipe size. The below numbers are based on minimum flow capacity of different sizes of PVC water lines.
The first calculation is for 1.5″ pipe. I use a low GPM in all my calculations such as 1.5″ pipe will easily carry 80 GPM at 40 psi. Each line size below is capable of 50% more given more pressure and clean smooth lines.
80 X 60 minutes = 4800 GPH X 8.34 lbs weight of one gallon = 40,032 X Delta “T” equals 800,640 BTU / 12,000 = 66 tons
1.5″ flows 80 GPM and carries 66 tons
2″ flows 127 GPM and carries 105 tons
2.5″ flows 190 GPM and carries 158 tons
3″ flows 273 GPM and carries 273 tons
These are minimum flow for these sizes, they will easily flow 40% to 50% more
So, depending on length of run and number of turns you have to make a decision.
Usually you don’t have to worry about a couple of hundred feet unless there’s a lot of variables. If you run too large of line it creates a pressure issue so balance is important. Instead of using a large pump our suggestion would be two or three pumps. Three pumps use lower HP. Most 1 HP pumps are 40/40 easily. 40 psi and 40 GPM on 1″ copper lines.
This example was written for a 10 ton chiller
You have more than enough water per BTU however you have to hold enough pressure or GPM to satisfy the equipment although the BTU load isn’t that much compared to volume of water.
A critical factor. Only return used water back to the chiller, use a small bypass to keep water in lines at set point.
If you do not flow unused water back to the chiller then you have more useable GPM and pressure to distribute the flow. Unless the pressure in the line is high enough to force water down each chamber something is going to starve. Most owners are flowing 75% of their water back to the chiller and using 25% or less of it for cooling. This artificially creates a need for GPM. When we do an install we do not attach the supply line to the return line. We use a small bypass to flow some water back to the return line to give a good temperature reading and to keep water flowing in the winter.
Most jacketed vessels are limited to around 15 PSI. Many manufacturers limit the psi to 12 psi. I have toured many of the factories building jacketed vessels.
The below is in reference to an existing brewery wanting to plan for the future when they purchase their new chiller.
If it were me and I was plumbing his system I would use 2″ supply with 2.5″ return. At the largest I would use 2.5″ with 3″ return. If you use 2″ I’d use two 2 HP pumps and on 2.5″ I would use 2 @ 2.5 HP. The sweetest would be 3 @ 1.5 HP, staged based on pressure. Have the second pump kick on if the pressure drops below a certain point. Then the third pump. The pressure switches are field adjustable. If you stop flowing most of the water back to the chiller you will most likely never have the second pump come on or the third pump. It would give excellent redundancy and flow. On either pipe size the three pump alignment would beat VFD. The staging I would use is based on the restriction of chilled water bypassing to the chiller. If your standing pressure without demand from equipment was 40 psi I would stage pump two at 30 psi and three at 15 psi. If you put the range too close your pumps will short cycle.
We build our chillers with a built in bypass from the pump head to the chiller. We use 3/8″ copper and insulate it. This water flowing over our evaporator raises our BTU rating. It also allows the pumps(main supply line from chiller) to be totally closed and run indefinitely without harm.
If you could evenly distribute the flow a 1 HP could supply 33 tons of water. The problem is you would have to have a flow regulator or pressure control on each vessel to make sure non starve. I’m not saying use a 1 HP but it’s easy to see how one could be used. It’s easier to buy a larger pump that can supply the needed pressure for even distribution.
Most customers don’t realize how frequency drives work. It either uses a pulse or it changes power to the pump. Either method uses more energy and drastically shortens pump life. The next two paragraphs are taken from a company that are experts in pressure regulating and flow. From Cycle Stop Valves Inc.’s website. They are based in Lubbock, Texas. They have much more information on their website.
These Variable Speed type pumps do not save energy, and do not make pumps last longer. To the contrary, varying the speed of these type pumps can increase the energy used by as much as 500% per gallon produced. Likewise, varying the speed increases the heat in motors, causes excessive vibration, and shortens the life of motors from other undue stresses.
So how do these people get away with lying? As they say, the Devil is in the details. Read the fine print carefully. Comparing a VFD to the most inefficient pump system possible is the usual way to show it saves energy. Many articles will barely mention discontinuing the use of a dump valve, lowering the pressure required, or even installing a smaller pump in the system. Although these are the real reasons for the documented energy savings, the VFD added to the big pump wrongfully gets all the credit.
Flow is reduced 5 times faster than the amp draw.
If you are considering VFD you should visit www.cyclestopvalves.com
This part is very important. The Chillking chiller cabinet with the components that stay at ground level is dry charged with nitrogen. We weld the lines shut, draw another vacuum and add nitrogen. This ensures a dry system upon arrival. They just need to cut the stub outs and weld in their lines. Pay close attention to keep the lines separate, they are marked as 1 and 2 for condenser 1 and 2. When they make the cut the dry nitrogen charge will leak out. It is not refrigerant. Only the condensers have refrigerant in them. They have the critical charge for the chiller. Then they draw a vacuum on the line sets and evaporator. After the standard 3 on 3 off vacuum they open the king valves on the condensers. The condensers have a pressure valve for low ambient. It does not allow the fan to come on until adequate pressure is attained.
When the installer is ready we can send all pressure settings to just double check everything. A manual is included in the electrical panel. There will be an ETL sticker that has critical charge in ounces and the pressures. The access is marked on the chiller.
The most overlooked thing in the manual is the drawing showing how to put a T in line to use for glycol access. Just as the return line enters the chiller install a “T” with the leg facing up. Install a threaded slip fitting into the upright leg and a cap or plug to seal the line. Use the same size plug or cap as the glycol return line, do not reduce it. This is used to fill the system and add propylene glycol. It is also for testing the strength of your glycol during your late summer checkup.
Very important! If it is very cold upon start up please allow time for the compressor heaters to warm the compressors before start up. We advise 15 to 30 minutes, this is to heat the oil in the compressor to give adequate oiling upon start up. These are very rugged Copeland scroll compressors however every step to extend compressor life will give you at least 15 years of dependable compressor life. Most of our original chillers using Copeland compressors from 20 years ago are running the same compressor.
If the chiller cabinet is lower than the equipment being cooled and you happen to have a power failure the liquid coolant will flow back to the chiller. It is a vented system so the tank could overflow. It is best to install two electrically activated valves at the discharge port and the return port of the glycol chiller lines. These valves open on power applied to the pump. They should be wired into the water pump circuit. This ensures that if the pump is running the valves are open. You can use a check valve on the discharge line however the return line requires a solenoid or motor driven valve. Valves can be purchased in various voltages, we advise using the low voltage for controls coming from the transformer. Our office can assist the installer with drawings depending upon the method used.
Chillking installs a low level float switch as standard practice on every chiller. This switch can be used to turn on a led, an alarm, auto fill, or all three. We feel the float switch is much more dependable than a side mounted sight glass plus we don’t charge for it. Our experience has been that the sight glass will turn opaque and age to the point that you cannot read it. They also get broken easily and leak. When it is on a chiller on the roof it is very difficult to check the level. An alarm or light wired in has proven to be the most dependable. Most customers prefer a buzzer or alarm. I feel this is best because with time the employees stop checking fluid level and a sudden buzz or ring will awaken them. When it sounds the chiller is not desperately low. It is 2″ to 3″ below the full mark.
Many of our new employees will be surprised at how many different methods, refrigerants, designs, solders, and construction methods go into designing or building a chiller. Chillking employees are exposed to a much larger “palette of color” than would be an average HVAC technician. What I mean is that some artist will use many colors to create a work of art while others may limit themselves to black and white.
Chillking employees will work most of the time with a refrigerant commonly known as Puron, Suva or Forane with a refrigerant code of 410A. This refrigerant was designed and engineered by Allied Signal in 1991. They are now a division of Honeywell. It was commercialized by Carrier Company because they were one of the first large equipment manufacturers that recognized its ability to produce higher BTU with less energy.
Brazed Plate Heat Exchangers
Their typical construction materials consist of stainless steel plates held together with a copper based brazing material. Water and refrigerant circulate in alternating plates. This style of heat exchanger can be used for both evaporators and condensers.
1. Their space efficient shape (rectangular allows for compact unit design.
2. The non-ferrous construction eliminates rusting.
3. The alternating plate design makes the brazed plate evaporators less susceptible to freeze damage when compared with shell and tube evaporators.
4. The small passages encourage turbulent flow, which can benefit heat transfer.
5. They are less expensive when compared with a shell & tube design.
1. They cannot be serviced (cleaned, leaked repaired, etc.…)
2. The smaller passages lead to a higher water side pressure drop.
3. They are subject to plugging/fouling, also due to the smaller passages.
4. Although they are typically constructed of stainless steel, the brazing material is copper based and can sacrificially corrode.
Shell & Tube Heat Exchangers
Their construction materials usually consist of a carbon steel shell with end plates and copper tubes. With a DX Evaporator, water circulates in the shell side while the refrigerant passes through the inside of the tubes. In a condenser, the water flows through the tubes while the refrigerant remains inside the shell.
1. Less water side pressure drop due to the larger tube size.
2. Tube leaks are easily located and plugged.
3. They can act as a liquid refrigerant receiver helping with pump-down and low ambient situations.
4. Much easier to service (clean and repair leaks).
5. A better solution for water derived from open cooling towers, rivers, lakes, sea coolant, and other fluids at risk of clogging in narrow spaces.
6. Rugged mechanical construction due to its thicker tube walls.
7. Tubes are available in a wide variety of construction types (Copper, Cupro-Nickel, Stainless steel, and Titanium)
8. The shell is also available in stainless steel, for sea water and other highly corrosive applications.
1. Less thermally efficient due to less total surface area.
2. Requires a larger space.
3. More expensive when compared to brazed plate.
4. In evaporators, the water is passing over a carbon steel surface.
For heat exchangers that use cooling tower water, river, lake or a similar source, it is highly recommended to use a Shell & Tube condenser because of its larger passages and lower probability of fouling and scaling. Shell & Tube heat exchangers can be easily cleaned just by removing the end plates and brushing the tubes. However, for situations that use a closed loop water source, or coolant such as glycol, a Brazed Plate condenser may be used to lower cost and achieve better thermal performance in compact design. When using a brazed plate heat exchanger, a strainer with an appropriate mesh size should always be used.
Source: Air Industrial Refrigeration, “Heat Exchangers Commonly Used for Evaporators and Condensers” 11/16/2017
Source: HumanNHealth.com, “Ozone Kills 99% of Bacteria, Mold and Viruses” 03/10/2016
It’s a common problem for owners to allow machines to run on city bypass water. THIS IS VERY IMPORTANT : One thing that is important to check is this, when the ice cream machine is off, is there still water flowing from the machine? Water flowing throughout the night and after an ice cream machine has finished cycling will increase water cost 60% to 75%!
On each ice cream or yogurt machine there is a valve that controls water flow. When the refrigerant gets to a certain temperature it correlates to the pressure needed to open or close the water valve that cools the refrigerant. In doing so it removes the heat from the machine. The water flows through the internal workings of the machine absorbing heat and goes to waste. That valve is supposed to close when the compressor is off and the refrigerant is cool. Those valves are famous for sticking on the water control side. You do NOT need a refrigeration technician to change it or to clean it. The refrigerant portion of the valve remains attached to the machine and you change the water operation portion only.
Prior to opening Chillking I owned a service company that was authorized to work on every brand of ice cream machine. The main troubleshooting service call was for malfunctioning valves.
I’m happy to help you with a chiller, even if you install new valves you most likely will still have large water bills. But it’s important to save as much water as you can while saving money. We had a customer with $9,000 water bills every month. All events were prior to a chiller and his original water bills were $12,000 a month. When he told me that I was in shock. I knew it should be better. He had a decrease in cost because the machines were running at lower pressure since the refrigerant was now cooler than ambient, thus reducing back pressure on the compressor. I told him that if he was considering a chiller there is no need to change the valves because the water would flow in a continual loop. He insisted we change the valves. We flew a technician to the eastern upper US coast. We found that seven machines had failed valves. Only one valve was working. The technician changed every faulty valve including the machine that was operating. Then all of his ice cream machines began to cycle water. His water bill dropped to $3,500 a month. So faulty valves were costing him $8,500 a month.
I explained how quickly he could recover his cost for installing a chiller, if only against his new bill of $3,500. In a few days he called me to order a chiller. I felt he would save another $2750 to $3,000 a month. His price for the chiller was $13,999. He saved a minimum of $3,000 a month, some months were $3,500. Even at $3,000 he paid for the chiller in five months. That is a tremendous savings. Had he installed the chiller a year earlier he would have saved, 12 months x $108,000. Ten years is over $1,000,000. ONE MILLION DOLLARS in ten years savings! $1,000,000 dollars!!!!
The size of chiller you need is based on how many ice cream machines you have. The other option besides three phase is single phase 240v. It’s the same voltage the dryer or electric range operates on. Single phase compressor over 5 tons is very difficult to find so the largest we build in single phase is 5 tons. 5 tons may work fine for you, how many machines do you have to run on the chiller?