FAQ – SRA
The SRA removes the “oil fouling” in an air conditioning or refrigeration system. In these systems, a compressor pumps the refrigerant around the circuit. That compressor needs oil to operate and that oil is circulated along with the refrigerant. Over time, the oil sticks to the walls of the pipes in a very thin layer and forms an insulation barrier between the refrigerant and the copper of the pipes. The SRA cleans the inside walls of the pipes and prevents the oil from again sticking to the pipes. Now, the refrigerant is in direct contact with the refrigerant so the system operates more efficiently.
With all the tests that we have done, we typically see an improvement of 15% to 25% in the efficiency of the system.
Yes. We guarantee that you will get a gain in efficiency of 10% or we will give you your money back.
The SRA product can be used with most types of air conditioning systems: • cars and tucks • refrigerated containers • residential systems • hotel systems • commercial and industrial units • walk in refrigerators
Your warranty should be unaffected by the addition of the SRA. The SRA will make the system operate more efficiently. That will translate to less maintenance and a longer lifetime for the system.
No, the system must be running when the SRA is installed.
You must turn on the air conditioning systems to install the SRA. However, the system needs to run only for a short while before, during, and after the installation. So it could be on for only ten minutes and might not cause too much disruption to the occupants of the building. If it is very cold outside (below 0°C (32°F)), you should not turn on the air conditioning system as you may cause damage to the system. In that case, wait until the weather is warmer before you treat the air conditioning system.
For a small system (like a residential or small office rooftop unit) the change is seen in hours. For large systems, it could take a few weeks.
The SRA is installed only once. Like the refrigerant, it never wears out and lasts as long as you own your system.
We have conducted scores of case studies and these are described in detail on our web site. No other company has the conclusive proofs of performance that Power Knot has. If you need to see a specific case study that we have done on equipment similar to yours, please contact us.
No. The utility companies provide rebates only for hardware products they can see and touch. Also, the amount of your savings depend on the age of your system and the time it has operated since being installed. Unlike a light bulb, the utility company cannot know exactly how much energy your system will use after it has been treated with the SRA.
Installation and Usage
You use 10% of the total oil capacity in a system. So, if a system has one gallon (4 litres) of oil, you add 13 oz (400 ml) of SRA. As a rough rule, this is about one US fluid ounce (30 ml) for each ton (3.5 kW) of refrigeration. So, a 30 ton (100 kW) system typically requires 30 ounces (900 ml) of SRA.
Not normally, and never on a hermetic system. However, on a semi hermetic system, if you have been adding oil to a system over the years, that oil is stuck to the inside of the pipes. It has not been dripping onto he floor like a worn out old car. After applying the SRA, all this oil will be returned to the system and therefore you may need to remove oil from the system to maintain the correct level.
It is injected into the low pressure port of the system while it the system is running.
On small systems we use a hand pump and on larger systems we use the same pump a technician might use to add more oil to the system. This is commonly called a Yellow Jacket bicycle pump.
The SRA will last the lifetime of the system. It never wears out and they never needs replacing. Because we don’t live forever, we warrant the products for five years.
Yes. However, any system where you install the SRA must be working well prior to the installation of the SRA.
If you evacuate and replace the refrigerant you don’t need to add any more SRA. However, if you have a catastrophic leak, we recommend adding a third of the original amount of SRA. If the leak happens soon after the SRA is installed, it may not have stuck to the insides of the pipes. In that case, you may need to put the full amount of SRA into the system again.
No. The SRA will remain in the pipes and no further application is necessary provided you replace the refrigerant you removed (because some of the SRA will be mixed with the refrigerant). You will lose some of the effect of the lubricity agent that is in the SRA. To restore that, add a fifth of the original amount of the SRA.
Yes. The SRA will be stuck to the inside of the pipes and you need to replace it after you change the coils.
No. Such systems operate so differently than the common refrigeration systems.
No. There is no effect on the refrigerant; none needs to be added or removed and you do not need to adjust the superheat or subcool.
No. However, if you regularly replace the oil in your system, change the oil and the filter drier prior to installing the SRA. We recommend you thereafter check the oil before changing it. It will probably last 50% longer than before.
A few minutes to a few hours, depending on the size and condition of the system.
Yes, we have arrangements with local service companies in many areas of the US. They can fully support the installation and commissioning of the SRA.
The SRA works on all common refrigerants, including R-22, R-32, R-115, R-123, R-125, R-134a, R-142b, R-152a, and blends of these including R-407(A~F), R-410(A,B), and R-502.
The SRA cannot be used with R-11, any of the R-6xx family, or any of the R-7xx family (including ammonia, R-717).
Our trained technicians can calculate the exact amount one they know the details of a system. However, to a first approximation, the usage is one US fluid ounce (30 ml) per ton (3.5 kW) of air conditioning.
No. The SRA is much more than an oil additive. SRA does include an oil additive to improve the efficiency of the compressor and works in a way similar to other oil additives. However, the major component of SRA removes “oil fouling.” The oil fouling occurs because the oil inside the compressor circulates with the refrigerant and sticks to the inside of the pipes, especially in the evaporator. That oil acts as an insulation barrier between the refrigerant and the copper (or aluminum) pipes. The SRA removes this oil thereby improving heat transfer between the refrigerant and the copper (and hence the air or water that is being cooled).
Removal of the oil fouling results in an improvement of between 15% and 25% in the efficiency of the air conditioning system. We guarantee an improvement of at least 10%.
The oil is returned to the compressor. It is still good oil and continues to lubricate the pump. Meanwhile, our product continues to do its job for as long as you own the system – you need to apply it only once.
Old lubricating oils would stick to the metal surfaces. As the surfaces moved the oil would shear and the oil had to be replaced often. If you replaced the oil in your own car 30 years ago, you had to do it frequently and the oil came out black. Modern oils have a detergent that prevents the oils from sticking. The oil functions by forming a barrier between the metal surfaces without adhering to them. Now, oils last much longer and we replace oil in our cars, for example, five or ten times as infrequently as before. The SRA helps to prevent the oil from sticking to the metal surfaces and this provides better lubricity to the compressor and therefore makes it and the oil last longer. In fact, the effect on the compressor is to reduce the vibration and power consumption when the compressor is running.
Yes, you need only a small amount (typically ½ oz, 15 ml) to make the air cooler and the system more efficient.
Yes, we or our business partners have treated water cooled and air cooled chillers with great success. The basics are the same on an air to air (DX) system or a chiller system: the SRA is added to the refrigerant circuit at a rate of 10% of the oil. The SRA is physically injected into the low pressure port of the system while the system is running.
There are two ways to prove performance: with an enthalpy test or with a power test. We have done both and there are detailed reports on our case studies page on our web site. The enthalpy test is quick and gives instantaneous results. However, it is easily fooled by poor measurement technique. However, if done correctly, it gives an accurate estimate of the efficiency gain within a few hours. The power test requires that you monitor the power consumption and temperatures for some time before treatment and also after treatment. For this you need special monitoring equipment that can log the data for some time. We recommend the system is monitored for a minimum of two weeks before installation and two weeks after installation. At a minimum you must monitor the power used by the a/c or refrigeration system. If the load conditions are changing you need to also monitor the temperature of the space being cooled and maybe also the supply air and return air temperatures. Also, you must monitor the outside air temperature. Whatever system you monitor and however you monitor it, you must ensure that it is not co-mingled. That is, it alone is cooling the space. If the system is co-mingled, you can perform and enthalpy test, but it is difficult to perform a power test. Logging is time consuming. Analyzing the data afterwards is laborious and difficult. You need equipment that must be kept in place and not disturbed until after you have completed the report. However, logging the power is accurate and thorough.
The system is operating more efficiently. That means it has less stress. That in turn means less wear and tear and improved longevity.
No. You can use the SRA in systems that have an evaporator temperature above –20°C (–4°F). This is typically any system with a cold space that operates above –10°C (14°F). Typical freezers to store food have a space temperature of –18°C (0°F). The evaporator for such a freezer operates at about –28°C (–18°F). This is too cold for the SRA.
Yes, you can still recycle the refrigerant after treating with SRA. There are two reasons: Most (over 99%) of the SRA remains in the system when you remove the refrigerant. Only a small part will be in the refrigerant. The SRA boils at a temperature much higher than the refrigerant so it is easy for the recycle company to separate the SRA from the refrigerant. When the refrigerant is removed from a system, it will usually have more oil in it than it will have SRA. The recycle company has no problem to separate the two.
Yes. The SRA lasts forever in a system. Just like the refrigerant, it never needs replacing.
Yes, but you won’t get the big improvement in efficiency. The oil fouling builds up over time so we recommend the system be at least two years old and must have had at least 2000 hours of service. On a new system, you will obtain an improvement in efficiency of about 3%.
A catalyst is a substance that causes or accelerates a chemical reaction without itself being affected. The SRA neither causes nor accelerates any chemical reaction within the refrigeration system. That is, the oil, refrigerant, and SRA are unaltered. Therefore, the SRA is not a catalyst.
No, We have proved the longevity of the SRA. Installations we did in 2009 are still functioning well.
Screw compressors rely on an oil film to make the rotor to rotor seal as well as to prevent wear in this area. The SRA does not interfere with this sealing process. We have treated screw compressors and no problems have ever been reported.
Purchase and Distribution
In the US, we have many HVAC companies that install the product. Contact us to find your nearest service company. Outside the US, we have authorized distributors that usually have exclusivity to a country or region. Power Knot does not sell directly to end users.
Power Knot carries stock and ships from Milpitas California.
We supply the SRA in 8 oz, 32 oz, and 128 oz (1 US gallon) containers (240 ml, 950 ml, and 3.8 l). For our large volume customers we also supply it in 5 US gallon containers.
The product is safe to transport by land, sea, or air. It is safe to store. You can put your fingers in the liquid; it is harmless (but you probably want to wash your fingers before eating any food!).
We normally use FedEx, but we can send it by any carrier of your choosing.
No. Once the SRA is installed, it cannot be retrieved.
Yes. The SRA must be installed by a fully qualified and certified HVAC technician. In the US, such person must hold EPA-608 certification.
The SRA can be kept indefinitely in a cool dark place (out of the sun and in an environment such as ordinary room temperature).
No. The SRA is proven to work every time. It is highly unlikely that it won’t work in your system.
Impact on the Environment
By making the system 15~25% more efficient, this usually means that the system uses 15~25% less electricity. That results in a great reduction of carbon footprint with a saving of significant CO2 production.
No. The SRA is environmentally friendly, non-toxic, non hazardous, and has no issues with disposal.
The SRA is a proprietary formula. However, it does not contain chlorine or sulphur. These elements could turn to hydrochloric acid (HCl) or sulphuric acid (H2SO4) inside the cooling system. Both of these acids are undesirable in the system.
Product Quality and Service
The SRA is made either in the USA or in China.
No. The equipment manufacturers have no incentive to recommend or approve of the SRA. They do not get paid to do so. In fact, because the SRA makes the equipment operate 15~25% more efficiently, it is likely to last 15~25% longer. That will result in a corresponding reduction in the sales of replacement units; this is a disincentive for the equipment manufacturer to approve of the SRA.
Yes, once installed, the SRA the SRA will continue to do its job forever.
It will last as long as you own the cooling system.
This should never be necessary. However, if it is desired, drain the refrigerant completely and then flush out the system with a solvent.
Power Knot and its global partners have installed SRA in systems from: • Bryant • Carrier • Compu-Aire • DataAire • Emerson • Fujitsu • LG • Liebert • Omega • Trane • York
The life of the SRA is indefinite. Like the refrigerant, it has no mechanism whereby it wears out. The savings from the SRA will continue year after year. However, as a practical matter, Power Knot provides a Performance Warranty for five years.