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I liked a lot, if I quedadaba any doubt about the state of the refrigerant, now I'm clear. Please Manu Might relocate the link's in this section rechargable fan that can not be accessed, thank you very much. I really want to meet you in Madrid, although not drink any beer glass sure we take, hehe really rechargable fan the best forum of professionals with which nobody could even dream, congratulations.
Hello everyone. True is interesting. I would want to make sure something after reading my post to see all the things so a little abstract. Reheat correct -> 4 º C - 9 C Subcooling rechargable fan right -> 4 º C - 10 º C to think there are all more or less agree, but according to the posts I've stated before all speak of the refrigerant R22. My question is: Are these temperatures are also valid for R134a, R407 and R410? and another question: finally for the gases and the R22 from excessive temperature as would be a gas outlet of the compressor? A greeting.
Re: supercooling and superheating rechargable fan 3 years 2 weeks ago # 58991 OFFLINE lafaraonadelfrio WHAT COLD THERE? Sevilla (SPAIN) Posts: 10969 Thanks received 452 Karma: 365
overheating is the result of utilization of the evaporator flooding and thus is the result of the output temperature and pressure of the expansion element rechargable fan and the suction pressure so that the subject passes through differences of two values, so that in these differences will give the effectiveness of this evaporator, no matter the gas you use as with different gases will be able to work at the same temperature, just vary the pressures of these because each gas have a different put pressure evaporate 0th C here I put a table of pressures is interactive so you can grind it with the mouse, a greeting www.pecomark.com / rdgr.htm
The discharge superheat temperature (outlet temperature of the compressor gas) if the gas depends on cuentión and evaporation temperature, suction superheat etc. To know this value must use a program like duprex and filling some values rechargable fan can meet the discharge superheat. Well, that or experience.
Thank you both. The truth is that I have to get a table for those llebarla always in your pocket. I'm learning a lot thanks to this forum. In what I can only seros useful .... might help you with vrv panasonic and daikin is the only thing I play at gigs. Thanks again ;).
Thank you both. The truth is that I have to get a table for those llebarla always in your pocket. I'm learning a lot thanks to this forum. In what I can only seros useful .... might help you with vrv panasonic and daikin is the only thing I play at gigs. Thanks again ;). Look at this post, specifically Chapter 14 Tables of saturation. Greetings www.forofrio.com/index.php?option=com_ku...iew&catid=6&id=51658
Re: supercooling and superheating 3 years 2 weeks ago # 59066 OFFLINE lafaraonadelfrio WHAT COLD THERE? Sevilla (SPAIN) Posts: 10969 Thanks received 452 Karma: 365
I suggest you see these videos although the expansion is by capillary them overheating and subcooling is explained between two very different concepts but if either should work on their values for the other acted properly
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And finally here is due to the calculation of our thermostatic expansion valve valve with orifice.

Today we'll explain how to calculate thermostatic expansion enthalpy tables valve is performed. For correct dimensioning a thermostatic expansion valve mechanical type is necessary to know and determine the following parameters: - Type of cooling-capacity evaporator - (Qe) temperature / pressure evaporation - (Te / Pe) Minimum coolant temperature -Temperatura/presión (Tc / Pc) at the inlet of the thermostatic valve condensation enthalpy tables (Tl)-pressure drop in the liquid line, evaporator-Retail (deltaP)
2nd-Then go to determining the potential enthalpy tables required to the valve and then, using the potential of the evaporator (Qe) to choose from, with some evaporation temperature, the required capacity of the valve. If you need to adjust enthalpy tables the cropping function of the refrigerant evaporator. Note: In the process of the calculation of thermostatic enthalpy tables expansion valve we consider that the provision of an evaporator rises when the coolant enters the evaporator enthalpy increase that may be selected by a smaller valve. Formula for determining cooling: vacuum enthalpy tables Delta = Tc - Tl
All valve manufacturers provide tables with correction factors relevant to cool, then choose the appropriate correction enthalpy tables factor (FSUB) coincides with the calculated value and determine the potential enthalpy tables required to the valve with the formula: deltaq sub = Qe / FSUB
3rd-At this point go to the port, use the pressure valve, evaporator temperature enthalpy tables and calculated to select the appropriate size of the potential hole in the corresponding table to choose the evaporating refrigerant capacity. Then change to choose enthalpy tables the type of thermostatic charge enthalpy tables and therefore if the work is normal or low temperature is always recommended an external equalizer. A practical example:
Refrigerant R134a (Qe) 6 Kw power evaporator, evaporation temperature (Te) -10 C, temperature of condensation (Tc) +30 C, the coolant temperature (Tl) +20 C, pressure drop (deltaP) 1.5 bar. Then we make our data as follows:
2 - power required by the valve: vacuum manifold Delta t = 30 - 20 = 10. C by the correction tables subcool manufacturers vacuum manifold Delta t = 10 C a correction factor equal to 1.08 is obtained and then the outlet valve is deltaq sub = 6/1.08 = 5.55. KW
And finally here is due to the calculation of our thermostatic expansion valve valve with orifice. Links of interest: as an air conditioner and a video of how to install an air conditioner works.
Categories enthalpy tables Airwell Air Conditioning Heat Pump Vacuum Pump Air Conditioning Carrier Air Conditioning Control and regulation DAITSU 2013 Danfoss enthalpy tables Refrigerant gases authorized Mitsubishi enthalpy tables air conditioning Refrigeration Installers Samsung
A / C Portable Air conditioning inverter air conditioner loses water bio architecture heat pump I calculate valves expansion air quality enthalpy tables CFC air conditioning 2013 Climate HVAC 2013 IFEMA How to save air conditioning how an A / C compressor inverter Danfoss EVRP 10 032F3298 Danfoss KP danfoss Danfoss kvp T2/TE2 leak detector PCE LD 1 evaporative cooling refrigeration cooling Expobioenergía 2012 authorized Gas Gas R-22 HCFC IFEMA 2012 Junkers air conditioning duct cleaning air conditioning plus wifi mont blanc new refrigerator not cooling energy label Olimpia Splendid air conditioning Panasonic enthalpy tables Etherea Plan Renewal A / A Air Conditioning questions enthalpy tables questions cooling Kyoto Protocol 2012 R-134A R-407C R-410A basic refrigeration air conditioning repair TESTO 570-2 4-way valve

However, the policy requires that all new vehicle temazcalli platforms that occur from 2017 use a r

- It has been developed to become one of the key substitutes for CFC and HCFC refrigerants. - Has similar characteristics as the cooling energy efficiency temazcalli and capacity than the R-12 and their toxicity is low. - In its UV version is made with a soluble ultraviolet dye to detect leaks more quickly and easily saving time and overhead. - Glasses and a UV lamps are required temazcalli only to discover their important benefits and advantages. Genetron advantages UV 134a and 134a Genetron temazcalli
- Has ODP = 0 (no chlorine) and is similar temazcalli to R-12 single-fluid - You can use the same expansion device (valve temazcalli hole) - It has a purity regulated by the pattern of ARI 700. - Has a known compatibility of materials.
However, the policy requires that all new vehicle temazcalli platforms that occur from 2017 use a refrigerant with a global warming potential (GWP) below 150, for that reason have developed Quimobásicos Honeywell HFO-1234yf in response to such a directive. temazcalli
The HFO-1234yf in contrast, is more friendly to the atmosphere, remaining there just 11 days, giving a GWP of 4. The GWP is a value used to compare different greenhouse gases that trap heat in the atmosphere.
The International Society of Automotive Engineers (SAE) validates the safety of using HFO-1234yf in automotive temazcalli air conditioning systems because, among all the proposed alternatives, temazcalli has better benefits in relation to the environment.
- Reduced environmental impact: Measured by the LCCP (Life Cycle Climate Potential) on HFO-1234yf has a lower environmental impact than carbon dioxide, as it has a potential for degradation of the ozone layer (ODP) of zero, a potential global warming (GWP) of 4 and an atmospheric lifetime of 11 days. - Increased security: The results indicate that HFO-1234yf is safe for use in automotive temazcalli air conditioning systems. - Low toxicity: Based on toxicity temazcalli tests performed, it is expected that HFO-1234yf is classified as ASHRAE Class A (Low toxicity - Low flammability. According flammability tests, including simulations of car crashes that were conducted the results demonstrate that HFO-1234yf is safe for use in air conditioning systems temazcalli - Low cost of transition. Given its compatibility with the current technology used in automotive air conditioning systems to R-134a, the transition cost is very low. - Global Application: For good energy efficiency, superior performance in high temperature climates and the minimum changes necessary systems, HFO-1234yf is well positioned to be a global solution.
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Therefore, Daimler has already informed the competent authorities of these facts and has also put i

Mercedes-Benz will continue using the refrigerant R134a in passenger vehicles - Motor Magazine
It was expected that the chemical harmless to the environment, the new refrigerant R1234yf were to be used worldwide in the automotive industry, so manufacturers and independent institutions had conducted a series of laboratory tests and crash to verify their behavior in different situations.
Although liquid ortega taco seasoning recipe test had confirmed that their behavior is not evil, Daimler AG conducted a series of additional tests on the basis of a new refrigerant test scenario based on the reality that goes beyond the legal requirements ortega taco seasoning recipe for its approval.
In this test scenario, have seen how the new refrigerant is dispersed dynamically reaching a high pressure when spilled near hot components of the exhaust ortega taco seasoning recipe system of the test vehicle, although researchers of the German group said in evidence laboratory, it is difficult that can ignite, but also noted that, in a compartment with a hot engine, it can be the case that the new refrigerant is inflamed.
Therefore, Daimler has already informed the competent authorities of these facts and has also put its findings available to all relevant associations and other vehicle manufacturers and has asked the authorities to continue using the R134a refrigerant tested and insurance on their vehicles, instead of the new R1234yf.
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The alternative to R-12 is tetrafluoroethane (CH2F-CF3) which belongs to the family of Hidrogenoflu

VIII -. Refrigerants and Lubricants
A. - B. Nature of Electricity - Electrical Quantities C. - Automotive Electrical Components D. - E. Basic Electrical Circuits - F. Starters - Alternators G. - Automotive Batteries h -. Course Ignition Systems Automotive Mechanic
A. - B. Basic Structure - C. Train and Suspension - Steering Systems D. - E. Brake Systems - Engine Combustion F. - G. Cooling System - Exhaust System H. - I. Broadcast System - J. Basic Electrical System - Carburetors K. - L. Injection System - M. Spendable Automotive - Maintenance Cycles and Refrigeration Automotive Misses crock pot lunch crock food warmer Basics Course
It is known that the main function of the device is to produce cold air picking up heat from the ambient air, as all fluid absorbs heat, refrigerants are used in air conditioning for its ability to absorb heat. These fluids crock pot lunch crock food warmer must meet a number of features for optimal effectiveness:
Favorable characteristics of pressure and temperature to ensure that the pressures are not very high in the condenser and evaporator too low value high latent heat of evaporation in order to achieve crock pot lunch crock food warmer greater effect refrigerator value of the critical temperature high enough to prevent the compressor compresses crock pot lunch crock food warmer the fluid to a pressure above the critical pressure, in which case no change of state occur in the condenser temperature lower evaporation at room temperature Safety crock pot lunch crock food warmer against fire and explosion Chemical stability and material compatibility that make up the circuit Low toxicity to avoid damage to persons handling Miscibility with lubricating oil used
Types of fluids: CFC: Chlorofluorocarbons (Example R12, R11, R502) are compounds of chlorine, fluorine and carbon. Contribute to the destruction of the ozone layer HCFC: hydrochlorofluorocarbons (Example R22, D124): They are compounds of chlorine, fluorine, carbon and hydrogen. Contribute to the destruction of the ozone layer and global warming through the greenhouse effect. HFCs: hydrofluorocarbons (Example crock pot lunch crock food warmer R134a, ISCEON 49) are compounds of fluorine, crock pot lunch crock food warmer carbon and hydrogen. Contribute to global crock pot lunch crock food warmer warming through the greenhouse effect
Dichlorodifluoromethane (C Cl2 F2) called R-12 or Freon 12 is a fluid characterized by a high heat of evaporation. It belongs to the family of chlorofluorocarbons, CFCs. Its boiling point is -29.4 C at atmospheric pressure. Exhibits high stability at high temperatures and non-reactive with most metals (except zinc and magnesium) also does not deteriorate the rubber tubing, however in the presence of water is highly corrosive because the reaction produces hydrochloric acid. Under normal conditions it is a colorless gas with a slight odor and produces no stains. It is miscible with mineral lubricating oils, taking crock pot lunch crock food warmer the necessary precautions crock pot lunch crock food warmer in the sizing of the pipes in order to ensure oil return to the compressor.
Under normal conditions it is not flammable or explosive, both liquid and gaseous state, however if it comes into contact with a flame or a hot metal decomposes into phosgene gas (mustard gas) which is a very poisonous gas, plus no should be contacting the fluid with eyes, because they can cause frostbite.
Unfortunately this compound rapidly reaches the upper layers of the atmosphere where the ozone, O3, is situated at an altitude of 15 km. and can remain for 120 years. Due to the effect of ultraviolet rays, the chemical degradation of R-12 is produced, releasing chlorine molecules, which react with ozone, an oxygen capturing, decreasing the concentration of ozone in the area. A chlorine molecule crock pot lunch crock food warmer can destroy between 50,000 and 100,000 ozone molecules. The ozone layer surrounding the earth's stratosphere level ensures protection against lightning
UV, which attack the human and animal organism and plant life. In addition, this layer limits the greenhouse crock pot lunch crock food warmer effect, keeping the heat balance of the planet by reflecting infrared rays toward Earth. Thus, the destruction of the ozone layer will cause the penetration of UV rays, with the consequent risk to the health and global warming.
The alternative to R-12 is tetrafluoroethane (CH2F-CF3) which belongs to the family of Hidrogenofluorocarbonos (HFC), its boiling point is -26.3 C at atmospheric pressure, so it presents a low toxicity, in the same so that the R-12, is not flammable under normal crock pot lunch crock food warmer conditions, yet is corrosive in the presence of water, since hydrogen fluoride is produced, is not miscible with mineral oils but

When starting a Scroll compressor must monitor their suction and discharge pressures, temperature i

Most Common Failures your Cooling System and its Solution in Country S After considering all the variables involved where lubrication and refrigerant charging, another critical in the implementation of cooling systems is the monitoring point of the compressor / evaporator.
When starting a Scroll compressor must monitor their suction and discharge pressures, temperature inside the camera, and especially amperage overheating or evaporator superheat and / or compressor and adjust if necessary. Therefore, we have: the amperage draw of the actual compressor field should be within 70% to 80% of the value of the RLA (FLA). To illustrate this case, considering a feeding 208-230/3/60 catalog and at the scroll compressor condensing units as previously cited, we note that the unit in question is a model mounted compressor ZF33K4E-TWC, it establishes chandi heffner duke a RLA value of 39.1 amperes. Under this line consumption in half from 27.0 to 31.0 amperes in the compressor is recommended. Regarding operating pressures, it is important to know what are the best values of operating pressure chandi heffner duke in a refrigeration system. Temp. Evap. = Temp. Desired Interior - 5.55 C C Temp. Evap. = -24.0 C - 5.55 C = - 29.55 C (-20.0 F) C is possible to know the operating suction pressure based on the temperature of operation chandi heffner duke of our cold room according to the following formula: With help of the tables that establish relations pressure - temperature, which can place pressure corresponds to a given evaporation temperature also known as suction saturation temperature. TABLE TEMPERATURE-PRESSURE VALUES IN RED = EMPTY VALUES BLUE = VAPOR PRESSURE (PSIG) / PRESSURE LIQUID (PSIG) º C º F R-12 R-22 R-502 R-134a AZ-50 (R-507) HP- 62 (R-404A) -45.6 -50 15.4 6.2 0.2 18.4 0.8 0.0 -44.4 -48 14.6 4.8 0.7 17.7 1.7 0.8 -43.3 -46 13.8 3.4 1.5 17.0 2.6 1.6 -42.2 -44 12.9 2.0 2.3 16.2 3.5 2.5 -41.1 -42 11.9 0.5 3.2 15.4 4.5 3.4 -40.0 -40 11.0 0.5 4.1 14.5 5.5 5.5 -38.9 -38 10.0 1.3 5.0 13.7 6.5 6.5 -37.8 -36 8.9 2.2 6.0 12.8 7.6 7.5 -36.7 -34 7.8 3.0 7.0 11.8 8.7 8.6 -35.6 -32 6.7 4.0 8.1 10.8 9.9 9.7 -34.4 -30 5.5 4.9 9.2 9.7 11.1 10.8 -33.3 -28 4.3 5.9 10.3 8.6 12.4 12.0 -32.2 -26 3.0 6.9 11.5 7.7 13.7 13.2 -31.1 -24 1.6 7.9 12.7 6.2 15.0 14.5 -30.0 -22 0.3 9.0 14.0 4.9 16.4 15.8 -28.9 -20 0.6 10.1 15.3 3.6 17.8 17.1 -27.8 -18 1.3 11.3 16.7 2.3 19.3 18.5 -26.7 -16 2.1 12.5 18.1 0.8 20.9 20.0 - According chandi heffner duke to the above table and temperature data Evaporation of -29.55 C and the refrigerant R-404a, obtain an indication where the ideal pressure to -30.0 C corresponds to 15.8 pounds. After obtaining the value, to subtract the losses in the suction pressure of about 2.0 psig, in this way, in our system we have a field suction pressure of about 13.8 psig. Overheating or Superheat In the refrigeration sector, especially talking chandi heffner duke about compressors / evaporators often hear, "You know what the value of the superheat of your cooling system?" Or "What is superheat?" The superheat are the additional degrees acquiring the output steam of the evaporation temperature (suction temperature), chandi heffner duke i.e., overheating, from where it finished vaporize liquid refrigerant. It is known that in a good cooling system, evaporator inside the coolant evaporate finishes in the last return (elbow) evaporator outlet. Once this evaporation wins grades refrigerant vapor enters the range of overheating.
It is important to remember that the suction pressure will also depend on the correct selection of the suction pipe diameters and the distance that exists between evaporator and condenser unit and other accessories chandi heffner duke fitted to it. How much is prudent that this vapor from the evaporator is hot? In general, the correct value of this parameter chandi heffner duke for the cooling systems is given according to the following. For differential temperature (DT) design evaporation 5.55 C (10.0 F), an superheat of 3.33 C is recommended to 5.55 C (6.0 F to 10.0 F) for best efficiency of your system cooling. For other selected temperature differential (DT) of more evaporation system, a good value of superheat is 6.7 C to 8.33 C (12.0 F to 15.0 F). The DT evaporation by 5.55 C (10.0 F) normally used in refrigeration systems where the ideal conditions include high indoor relative humidities that make it possible to preserve chandi heffner duke products such as meat, fruit, vegetables and seafood in

, Cascade systems have been used for applications where the compression ratio of the refrigerant is

Cascade Systems and Applications cascade systems have been used for applications where the compression ratio of the refrigerant is too high and / or where evaporation actually lower temperatures (<-50C) are required. Lately this type of system has become more popular to be necessary in low temperature catering food warmers applications using R744 (CO2) as a refrigerant in systems known as subcritical. Different sectors are in cascade systems the best solution for efficiency catering food warmers and performance in low temperature systems.
, Cascade systems have been used for applications where the compression ratio of the refrigerant is too high and / or where really low evaporation catering food warmers temperatures (<-50C) are required. Lately this type of system has become catering food warmers more popular to be necessary in low temperature applications using R744 (CO2) as a refrigerant in systems known as subcritical. What is a cascade system? A cascade system consisting of two independent systems of a stage, where the system with lower evaporation temperature used exchanger as condenser for rejecting catering food warmers heat therefrom, using the system evaporator with higher evaporation temperature. Usually use different refrigerants and their application is mainly for low or ultra-low temperature. (See diagram 1 and 3). Figure 1 two sets of cascaded stage = System Advantages of using a cascade system compression ratio of each system decreases, which causes the increase in volumetric efficiency of each of the stages and, therefore, the system as a whole is more efficient so that less displacement of the compressor is also needed. Also, the discharge temperature (see Figure 1) is decreased compared to a single stage system, which benefits the oil temperature and good lubrication of the compressor. Compression ratio PR, where P2 is the discharge pressure in psia and P1 is the suction pressure in psia. Compression ratio is the result of dividing the discharge catering food warmers pressure catering food warmers and suction pressure in psia. Psia = psig Psig is +14.7 psi gauge pressure. Psia is the absolute pressure including atmospheric pressure.
Furthermore, commonly used high-pressure refrigerant called whose characteristics allow the suction pressure is positive and not be necessary to work under vacuum, even when the saturated suction temperature (TSS) is very low. The R23 and R508B refrigerants catering food warmers are the most popular for these applications.
R-22 (psig)
2.6
7.4
13.2
20.1
28.2
37.7
48.8
61.5
76
92.6
121
168
226
297
382
To use a cascade system is needed to note that the compressors are within applicable limits, which are well lubricated and ensure that no liquid gets by suction. In the high system this is not a problem as it is basically a system of known MT.
For low system, other parameters have to care. For example the return gas temperature should not be less than -60 C as a precaution not to damage the compressor, as this is made of cast iron.
You should also take care of the oil temperature to ensure you have the proper viscosity for both to return the oil to adequately lubricate the compressor. Normally a temperature of the gas return overheated compressor or high (> 20K) is required. For this exchanger between the suction line and liquid used.
In the case of oil, it has to prevent this go to the system having an oil separator Generously sized and high efficiency. Failure to return the oil, perhaps necessary cycles "thaw" is to raise the suction pressure, mass flow increase and decrease oil viscosity with increasing temperature the same and so this return to the compressor. Other coolant may be used to help decrease the viscosity of the oil as the R600 (butane) or R601 (pentane). Normally this method is a must try adding only grams of these refrigerants to obtain the required result. The amount of R600 or R601 depends on the system size.
Moreover, when working with such low temperatures, both pipe insulation and all parts that are exposed and have a lower temperature than the dew and this being sufficient insulation in the parts where the temperature is below required 0 C. This is to prevent condensation and / or freezing of moisture in the atmosphere.
By high pressures with these refrigerants (R508B, R23, R744) is