Monitoring of oil concentration in a refrigeration cycle

 

Decades of experience show that measurements in research, especially in the refrigerant circuit, are time-consuming and complicated. Sampling is often difficult or even impossible. Therefore, the relationship between oil and refrigerant must be estimated using indirect methods.

The aim is to find out how efficiently a cooling system works depending on the oil concentration. The information obtained from the measurements provides information on how the processes in the compressor take place and when it is no longer operational.

SensoTech has developed the inline solution LiquiSonic® OCR, which offers unbeatable advantages, in order to carry out the measurements as precisely as possible.

What if the ratio between oil and refrigerant was known at all times and with high precision?
What if it were no longer necessary to take costly samples to determine the oil/refrigerant ratio?

With LiquiSonic® OCR, comprehensive information about the refrigerant process is continuously available. The permanent knowledge of the concentration ensures optimal process control, while the fast approach to the optimal oil/refrigerant ratio reduces the adjustment time.

Contact us

Efficiently determine the optimum ratio of refrigerant and oil with LiquiSonic® OCR

SensoTech makes it possible to have precise knowledge of the concentration of compressor oil in refrigerant at all times. Accurate inline measurements eliminate the need for time-consuming and error-prone sampling. Measured values are available at all times and are updated every second.

 

Maximum precision when monitoring oil in the refrigerant circuit

SensoTech places the highest value on precise measured values when monitoring the oil concentration. The determination of the oil concentration is based on pressure, temperature and sonic velocity measurements in the liquid refrigerant. This highly accurate measuring principle enables precise adjustment of the desired oil circulation speed.

Continuous determination of the oil concentration instead of selective measured values

The major advantage of online oil condition monitoring is the permanent availability of the measured values. As the data is updated every second, the operator has precise knowledge of the measured oil concentration at all times. Time-consuming adjustment of the oil concentration in the circuit is therefore a thing of the past.

 

Monitoring a wide range of refrigerants with one refrigerant measuring device

SensoTech impresses with sustainable and comprehensive process solutions. A total of up to 32 product data sets (calculation models) can be stored in the controller. This makes it easy to monitor a wide range of refrigerants with the LiquiSonic® measuring technology. Thanks to decades of experience and the manufacture of the measuring devices, there is almost no refrigerant left that has not yet been measured by SensoTech.

Selection of measured refrigerants

  • R134a
  • R407c
  • R410A
  • R744
  • R1234yf
  • R1234ze
  • R290 (Propan)
  • R1233zd (E)
  • R407A
  • R404A
  • R454-B
  • R454-C
  • R717 (Ammoniak)

Selection of measured compressor oils

  • D11
  • ND12
  • PAG
  • ACC-HV
  • POE 68

Comprehensive support for the analysis of oil in the refrigerant circuit

  • Clarification of the framework conditions
    The first step is to discuss with the user which medium is to be measured. SensoTech engineers check whether the combination of refrigerant and oil is already available in the existing database. If this is not the case, the feasibility of the measurement is determined in the in-house laboratory.
     
  • Clarification of the specification for the measurement of oil in refrigerant
    Once the measurement task is clear, specifics are clarified. Among other things, whether special materials, installation variants or special accessories are required for monitoring in the refrigerant circuit. The LiquiSonic® OCR system developed for this application, for example, already has a special measuring head and an adapter vessel. This equipment enables easy integration into the refrigerant circuit.
     
  • On-site installation qualification on therefrigerant circuit
    SensoTech can support the entire process on request. Our application engineers check that the measuring system is installed correctly and check that the first measurements run correctly.
     
  • Regular training and further education
    SensoTech offers additional webinars and training courses for various applications. This gives the operator the opportunity to get to know the measuring system in advance or to discover new functions afterwards.
     
  • Provision of new data sets for oil in refrigerants
    The LiquiSonic® measuring system is not limited to a specific refrigerant or oil. Different refrigerants, such as the refrigerant R32 and R134a, are analyzed in the in-house SensoTech laboratory. The use of a different refrigerant at a later stage is not a problem. SensoTech simply calculates a new data set, loads it onto the controller and the oil content in the new refrigerant can be determined.
     
  • Advice on follow-up projects
    SensoTech's expert team is on hand to answer any questions about the projects or other applications.

Practical application example of already measured refrigerants

There are countless refrigerants in use worldwide. As a globally active company, SensoTech has already implemented countless projects with partners.

 

Oil circulation rate in R410A

  • Mainly used in refrigeration and air conditioning systems and in heat pumps in buildings
  • Very accurate inline determination of the oil concentration
  • Replacement refrigerant for banned R22 systems

Refrigerant analysis for R1234yf

  • 357 times more climate-friendly than other refrigerants used
  • Used as a replacement for R134a in new cars
  • Works more efficiently at higher temperatures
  • Used in automotive air conditioning systems

Oil in refrigerant R134a

  • Banned in new cars within the EU, so often used outside the EU
  • Worldwide use in automotive air conditioning systems
  • R134a is considered the standard reference worldwide

FAQ on determining the concentration of refrigerant oil

If you have any questions about measuring the oil concentration in the refrigerant circuit or the LiquiSonic® OCR measuring system, the competent SensoTech team will be happy to help.

Frequently asked questions:
 

  • Why is taking a sample to determine the concentration of the refrigerant-oil mixture problematic?
    Taking a sample to determine the concentration is inaccurate and cumbersome, as it interferes with the closed system. In general, refrigerants volatilize as soon as they come into contact with air. The samples amount to approx. one liter. The analysis is carried out in the laboratory. The concentration of oil in refrigerant to be determined is only available after some time and is only a snapshot. The missing sample quantity ensures that the measured value does not reflect the current concentration. The system first has to settle again. Real-time inline monitoring is therefore preferable to sampling.
     
  • What is the purpose of the oil in a refrigeration system?
    The oil in the refrigeration system lubricates the compressor and ensures that it functions smoothly and does not suffer any damage. Attention must be paid to the perfect mixing ratio of oil and refrigerant. The rule here is: as little oil as possible, but as much as necessary. Too much oil can reduce the cooling capacity, among other things.
     
  • What happens if there is too much oil in the AC system?
    If there is too much oil in the AC system, the cooling capacity is reduced. This reduction means that the AC system only works to a limited extent, meaning that more time is required for the desired cooling or the desired temperature cannot be reached.
     
  • What type of oil is used in the refrigerant?
    There are a large number of combinations of oil and refrigerant that are used in a wide variety of compressors. The exact type of oil used depends entirely on the compressor manufacturer, as the respective compressors are only suitable for certain oils.
     
  • Can the refrigerant in the air conditioning system be replaced with a different one?
    While the measurements can be carried out in any known refrigerant, not every refrigerant can be used in every air conditioning system. If a refrigerant other than the previous one is used, it can attack and damage the compressor seals.

 

Request now