Hvac superheat formula

Superheat, a term often thrown around in the realms of thermodynamics and HVAC systems, holds the key to unlocking the full potential of temperature control. In this guide, we will unravel the mysteries of superheat, providing you with a detailed understanding, practical insights, and expert recommendations. ... Breaking down the formula for ...

Hvac superheat formula. That's a great question and it's a really simple formula that you can use in the field and it can help you get out of that bind if you don't have the OEM data to figure out where the charge needs to be and the formula for that is is going to be three times the indoor wet bolt temperature minus 80 minus the outdoor ambient temperature and divide ...

Q: How Do You Calculate the Target Superheat of a Residential Air Conditioner and Heat Pump? A: Well, there's a very simple formula for that and the formula is three times the indoor wet bulb temperature minus 80 minus the outdoor ambient temperature and you divide the results by two

Take low side pressure and p/t chart .convert low side press. to temp. then take line temp of suction line near condensing unit and subtract the two and the diff. is superheat. Reply. 07-16-2005, 09:59 PM #3. fitter638nyc. Professional Member. Join Date. Apr 2004. Posts. 395.wattage = the rated power of the fan motors (Watts) 1000 = convert from watts to kw. In this cold room evaporator we'll be using 3 fans rated at 200W each and estimate that they will be running for 14 hours per day. Calculation: Q = fans x time x wattage / 1000. Q = 3 x 14 hours x 200W / 1000. Q = 8.4kWh/day.Next, attach the PV350 to the suction line service valve (or refrigerant service port on your manifold gauge set). Make a note of the pipe temperature and pressure. This pressure reading will be that of the boiling refrig-erant inside the evaporator, assuming no abnormal restric-tions exist within the suction.The superheat setting is an essential parameter to ensure the TEV operates effectively. thermostatic expansion valve (TEV) Superheat refers to the additional temperature increase of a gas after it has fully transitioned from a liquid to a gas phase. In the context of a TEV, superheat is the temperature difference between the refrigerant gas at ...Superheat is a measurement of the temperature a vapour is above its saturation or boiling point. Superheat can be measured in any vapour such as steam or refrigerant. There are two important superheat readings that can be taken on a system. The evaporator superheat and the system or compressor superheat. You will get different results …A practical definition for wet bulb: for a sample of air at a given temperature and moisture content, it is the temperature to which air can be cooled via evaporation. Example: dry bulb temperature outdoors is 90 degrees. Wet bulb temperature is 70 degrees. Turn on a swamp cooler fan and wet the pads real well.You can enter altitude, DB and one of WB,DP or RH and the app will compute the remaining parameters. The difference in enthalpy is displayed and if you enter an airflow the total change in heat content in btu/hr will be displayed. The airflow page has added the ability to compute duct parameters for oval ducts.All in One Slide Rule R22 & R410a SuperHeat & SubCooling Charging Duct Calculator Air Conditioning and HVAC Troubleshooting

Hvac charts Superheat, subcooling & temperature pressure chart 8.3"x11.8" flexible Superheat charging chart r22 subcooling calculator amazon conditioning trouble refrigeration air Superheat . ... How to calculate subcooling? formula, subcooling calculator (r22, 410aEffect of subcooling on r22 mass flow rate. fig. 20 - effect of R22 subcooling ...Turn the thermostat to cool and set the target temperature at least 10 degrees lower than the indoor temperature. Let the system operate for at least 10 minutes to let pressures equalize. Record the suction line pressure. Use a temperature measuring device to measure the temperature of the suction line.Apr 22, 2024 · Now you look at your digital thermometer and see the suction line temperature is 53°F. These readings would indicate you have 10°F of superheat (53-43 = 10). Calculate subcooling. Once you know superheat, you can determine subcooling to see what is happening to refrigerant on the system’s high-side. By keeping track of superheat, HVAC professionals can ensure that the refrigerant is neither overheating or damaging the compressor overall. Superheat can ultimately tell a homeowner a lot about their HVAC system. For example, a superheat that is too high might indicate the refrigerant is overcharging. If it is too low, it may mean the ...9 Oct 2023 ... 115°F – 100°F = 15°F subcooling. Conclusion. Calculating superheat and subcooling is crucial for HVAC technicians to diagnose system performance ...SuperheatCalc—SuperheatCalc is a free app in the Apple App Store and Google Play, enables HVAC service technicians to calculate target superheat for systems using fixed-orifice expansion devices, superheat and subcooling for 26 refrigerants, and airflow and psychrometric calculations to aid with field service of HVAC&R equipment.The app was a winner of ASHRAE's 2016 Apps Contest.Overall Process: Enter refrigerant, temps, and pressures. The math is done for you; superheat calculations, subcooling calculations, and airflow calculations all display Target, Actual, and Difference. Repeat steps 1-2 until all HVAC Diagnostics check out as "Okay"; send system status report VIA text message or email as needed.

Superheat is a crucial factor in HVAC systems that helps ensure optimal performance and efficiency. In simple terms, superheat refers to the temperature difference between the refrigerant vapor and its saturation temperature at a particular pressure. It plays a significant role in the refrigeration cycle by indicating the amount of heat ...Superheated steam. Superheated steam is steam at a temperature higher than its vaporization point at the absolute pressure where the temperature is measured. Superheated steam can therefore cool (lose internal energy) by some amount, resulting in a lowering of its temperature without changing state (i.e., condensing) from a gas, to a mixture of ...Superheat and Subcooling are technical readings in an HVAC that measure the Freon (refrigerant) reading. Superheat measures the Freon boiling point in gas form while subcooling measures the Freon in liquid form below the evaporation level. To calculate superheat and subcooling measurements, a specific Mathematical chart is used, and the process ...An Excel spreadsheet for calculating target and actual superheat for R22 refrigerant. This is commonly used when charging an air conditioning / HVAC system utilizing a fixed orifice metering device. The exact values are calculated based upon your input temperature and pressure measurements.Charge 90% liquid of the original R-22 charge and let the system run for 20 minutes. Add liquid refrigerant to attain target superheat/subcooling. Properly label the system as being retrofitted with Forane ® 427A (R427A). For Forane ® 427A (R427A) system labels, contact our customer service department in the US at (800) 245-5858 (if you are ...

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How To Check Evaporator Superheat - it is very important for any HVAC and refrigeration technician performing service, maintenance or start ups to understand...All of these articles deal with refrigerant pressures, states, and conditions as applied to a refrigeration system with a refrigerant like R-134a that is not a blend. search. Search search ... Superheat always refers to a vapor. A superheated vapor is any vapor above its saturation temperature for a given pressure. In order for vapor to be ...If the actual subcooling is higher than the target subcooling, the unit’s refrigerant charge level is overcharged. Some refrigerant will need to be recovered into a recovery bottle. • Actual Subcooling +/-3° F Target Subcooling = Correct Refrigerant Level. • Actual Subcooling < Target Subcooling = Add Refrigerant.KV: Flow correction factor due to viscosity (KV = 0.9 to 1.0 for most HVAC applications with water) KN: Capacity correction factor for dry saturated steam at set pressures above 1500 psia and up to 3200 psia (KN = 1.0 for most HVAC applications) KSH: Capacity correction factor due to the degree of superheat (KSH = 1.0 for saturated steam)The SI equivalent of this formula would be: TSH=IWB- (OAT-IWB)/2-4.44. In my understanding, this formula provides an approximation for the expected line temperature and 4.44C (40F) represents Tevap. The indoor wet bulb (IWB) and outdoor dry bulb (OAT) temperatures represents the boundary conditions in terms of temperature in which the equipment ...Superheat is a way to ensure that the system is boiling off all of the liquid before it exits the evaporator. Refrigeration and air-conditioning systems may produce different superheat readings, but they are all determined the same way: by measuring indoor wet bulb and outdoor dry bulb measurements and using a pressure-temperature chart.

g. Calculate isentropic efficiency by Equation 1: µIsen = (h2Isen - h1)/ (h2 - h1) h. Calculate power by Equation 2: Estimating Efficiency - Shortcut Method. The isentropic path exponent (k) or ideal gas heat capacity ratio (k=CP/CV) can be calculated by the correlation presented in the May 2013 TOTM: Where:Superheat Charging. To charge a system using superheat, you will need to monitor the actual temperature of the low-pressure suction line, the saturation temperature of the low side suction gauge, and the indoor and outdoor temperatures entering the unit(s).. Most, if not all, manufacturers have a charging chart available with their respective units. With the information you have gathered on ... Superheat and subcooling are two important concepts in HVAC. Superheat is the number of degrees a vapor is above its boiling point at a specific pressure. Subcooling, on the other hand, is the number of degrees a liquid is below its freezing point at a specific pressure. By keeping track of both superheat and subcooling, technicians can more ... Jess Gordon is the service manager at Tempo Mechanical Services, Irving, TX. The company was Contracting Business magazine’s 2003 Residential Contractor of the Year. Jess can be reached at 972-579-2000, or by e-mail at [email protected]. Superheat is a way to ensure that the system is boiling off all of the liquid before it exits the evaporator.Our 300 question HVAC practice test provides: A 100 question EPA 608 practice test comes with our materials. Take this free HVAC practice test to see how prepared you are for an HVAC certification exam. 1. a. Open area of wall and low to the ground. b. Behind appliances and high on the wall. c. Open area of wall and high on the wall.Step 10: Compare Superheat to Recommended Values. Refer to the manufacturer's specifications or industry guidelines to determine the recommended superheat range for the specific HVAC system and refrigerant type. Compare the measured superheat value to the recommended range to assess system performance. Step 11: Adjust Superheat (If Necessary)Here is the formula for calculating superheat and total superheat: Superheat = T vapor after evaporator coil exit - T saturated refrigerant when it turns to 100% vapor. Total Superheat = T vapor at service valve; prior to entering the compressor - T saturated refrigerant when it turns to 100% vaporA Superheat Subcooling Calculator can help us achieve these precise calculations quickly and conveniently. Definition. Superheat Subcooling refers to two separate but interconnected processes in an HVAC system. Superheat is the surplus heat added to a refrigerant, beyond its boiling point. Subcooling refers to the cooling of the refrigerant ...

The Target Superheat Calculator is a valuable tool used in the field of HVAC (Heating, Ventilation, and Air Conditioning) to determine the optimal superheat level in a refrigeration system. Superheat refers to the temperature increase of a vapor above its saturation temperature at a given pressure. Achieving the correct superheat is crucial for ...

Low Superheat = Too much Refrigerant is going through the Evaporator. High Superheat = Not Enough Refrigerant is going through the Evaporator. Condenser = Sub-Cooling: Low Sub-Cooling = Not Enough Refrigerant is going through the Condenser. High Sub-Cooling = Too much Refrigerant is going through the Condenser.Since it seems like the formula was derived from a table I can see why this might be the case. For now the best thing for the conversion would be to use the table using the WB and DB values converted from C to F. After finding the superheat convert the superheat back to C but using the technique mentioned earlier (multiply by 5/9).26 Jul 2023 ... To calculate the subcooling temperature, subtract the liquid line temperature from the saturated liquid temperature. For the formula above, the ...In this HVAC Training Video, I Explain what Superheat is by Looking at an Evaporator Coil, TXV Metering Device, and Refrigerant Flowing from the Metering Dev...Suction superheat is a significant measurement. The point of taking that measure is a few inches from the suction service valve at the compressor. My rule of thumb for that superheat is: No less than 20 °F superheat and no more than 60 °F superheat! This is a "rule of thumb" and is only recommended as a guideline. The importantThe increase in temperature above saturation is described as the refrigerant’s superheat value. For example, at 18.42 psig, R-134a has a saturation temperature of 20°F. If its measured temperature is 30°F, the refrigerant is said to be superheated by 10°F. One useful area to measure the refrigerant’s superheated value is at the exit of ...No, the refrigerant is very close to being saturated. An infrared thermometer is the best tool to measure superheat. No, a contact thermometer should be used. A superheat reading indicates that there is liquid refrigerant at the location. No, superheat indicates vapor refrigerant. What is subcooling. Liquid refrigerant cooled below its ...I realize there is a calculation for your target superheat (eg. (IWB)*3-80- (OAT)/2=Target Superheat. However most units that I have come accross DO NOT specify the target subcooling (I speak of TXV/13 SEER units of course). I was wondering if anybody here knew of some calculation to determine this.When it comes to finding the right HVAC system for your home or business, there are many factors to consider. With so many options available on the market, it can be overwhelming t...

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Theory of Rankine Cycle. The Rankine cycle was named after him and describes the performance of steam turbine systems, though the theoretical principle also applies to reciprocating engines such as steam locomotives.The Rankine cycle is an idealized thermodynamic cycle of a constant pressure heat engine that converts part of heat into mechanical work. . In this cycle, the heat is supplied ...Delta T = 77°F - 56°F = 21°F. We can see that delta T is 21°F. This is normal delta T. The normal delta T range is between 18°F and 22°F. The HVAC school refers to this as "It should be 20°F, of course" lazy rule. Now, normal delta T doesn't necessarily mean that everything is alright with your AC unit.How to Calculate Superheat. Superheat, a term often thrown around in the realms of thermodynamics and HVAC systems, holds the key to unlocking the full potential of temperature control. In this guide, we will unravel the mysteries of superheat, providing you with a detailed understanding, practical insights, and expert recommendations. Steam or vapor in the HVAC systems is also categorized as gas. Superheat usually happens when a gas, vapor, or steam is heated to a temperature that is above the billing point of that material when it is in liquid form. For example, water at sea level starts to boil at 100°C in liquid form. You can experiment to see what superheat is by ... The high-pressure (HP) setting for R404A can vary depending on the specific refrigeration system and its operating conditions but typically falls between 200 and 250 psi. What is the ideal range of subcooling? The ideal range of subcooling for R404A is generally around 10 to 20 degrees Fahrenheit.As energy costs continue to rise, many homeowners are looking for ways to reduce their energy bills. One of the most effective ways to do this is by taking advantage of government ...Target superheat = (3 * Wet bulb temperature – 80 – Dry bulb temperature)/2. Target superheat = (3 * 64 – 80 – 86)/2. Target superheat = (192 – 80 …Superheating. In thermodynamics, superheating (sometimes referred to as boiling retardation, or boiling delay) is the phenomenon in which a liquid is heated to a temperature higher than its boiling point, without boiling. This is a so-called metastable state or metastate, where boiling might occur at any time, induced by external or internal ...Solving problems using R134a refrigerant properties tables such as enthalpy and entropy given a temperature or pressure. ….

Superheat & ΔT Calculator °F °C: brand . indoor wetbulb : indoor drybulb : outdoor ambient: For target SH enter indoor wet bulb & outdoor dry bulb. ...The superheat value should be 4-8K (Kelvin). If the Superheat value is too high then the evaporator is not fully flooded with cold liquid refrigerant causing the evaporator to be inefficient. If the superheat value is too small of even 0K (Kelvin) this means that liquid is coming out of the evaporator and back to the compressor.HVAC Superheat Calculator Measuring the exact superheat values on different temperature points is important to keep running the HVAC, specifically the air conditioning devices, efficiently and prevent damage from all possible HVAC issues. ... To calculate HVAC load, you can use this formula, (House surface in square feet) x (height of the ...Steam at 213 degrees F is superheated by 1 degree F. Superheat is then any temperature of a gas above the boiling point for that liquid. When a refrigerant liquid boils at a low temperature of 40 degrees in a cooling coil and then the refrigerant gas increases in temperature, superheat has been added. If this refrigerant changed from a liquid ...24 Nov 2019 ... Now to bring it all home we take the evaporator saturation temperature from step 2 and add the required superheat from step 1. ... The formula for ...At Superheat, we understand the pains associated with inefficient on-site heat treatment services. We've integrated remote operation technology and equipment advancements with digital project management and quality assurance platforms to produce the most efficient, state-of-the-art, on-site heat treatment solution.HVAC Charts - Your Source for Heating & Air Conditioning Charts and Supplies. R-22 Superheat & Subcooling Calculator. This tool is used for charging cooling systems that use R-22 Refrigerant. One side of this tool is a slide chart used for calculating superheat for a NON-TXV system and the other side is a slide chart used to calculate ...If the cooling load decreases back to normal, the superheat temperature will reduce. The sensing bulb will detect this and will begin to reduce the flow of refrigerant into the evaporator. The refrigerant in the capillary then flows back to the bulb and the main valve begins to close. The superheat temperature will also start to rise as this ... Hvac superheat formula, 26 Jul 2023 ... To calculate the subcooling temperature, subtract the liquid line temperature from the saturated liquid temperature. For the formula above, the ..., Superheat is the temperature of refrigerant vapor above its boiling point, which makes sure the refrigerant remains in vapor form as it exits the evaporator coil. Subcooling, on the other hand, is the temperature of the refrigerant liquid below its boiling point, which guarantees that the refrigerant stays in liquid form as it leaves the condenser., In This HVACR Training Video, I show how to check the charge. I discuss why technicians should check Total Superheat along with Subcooling when checking the ..., Turn the thermostat to cool and set the target temperature at least 10 degrees lower than the indoor temperature. Let the system operate for at least 10 minutes to let pressures equalize. Record the suction line pressure. Use a temperature measuring device to measure the temperature of the suction line., 1. Let Cp be the specific heat at constant pressure for superheated vapor. S2=S2' + 2.3 Cp Log T2/T2' from which Cp can be calculated. Then calcuate h2= h2' + Degree of superheat. T2=Temperature ..., The superheat value should be 4-8K (Kelvin). If the Superheat value is too high then the evaporator is not fully flooded with cold liquid refrigerant causing the evaporator to be inefficient. If the superheat value is too small of even 0K (Kelvin) this means that liquid is coming out of the evaporator and back to the compressor., Next, attach the PV350 to the suction line service valve (or refrigerant service port on your manifold gauge set). Make a note of the pipe temperature and pressure. This pressure reading will be that of the boiling refrig-erant inside the evaporator, assuming no abnormal restric-tions exist within the suction., Originally published on June 24, 2013. Understanding TXVs. Since the minimum efficiency regulation changed to 13 SEER in January 2006, most OEM systems now incorporate a thermostatic expansion valve (TXV) style metering device as the standard for air conditioning systems. It is now extremely important for the HVAC technician to understand the design and operation of this type of valve., You get superheat when you have 100% vapor, and you have subcooling when you have 100% liquid; any liquid-vapor mixtures are in a saturated state. We usually measure superheat outside at the suction or vapor line. It's best to take the superheat reading as close to the port as possible. Anything in the saturated state is boiling; you can only ..., Superheat Method. NOTE: Indoor airflow should be within +/- 20 % of rated cfm. 1. Purge gauge lines. Connect service gauge manifold to base-valve service ports. Run system at least 10 minutes to allow pressure to stabilize. 2. For best results, temporarily install a thermometer on the suction line near. the compressor., Superheated steam at 3 bar g with 10 °C of superheat (154 °C) is to be used as the primary heat source for a shell and tube process heat exchanger with a heating load of 250 kW, heating an oil based fluid from 80 °C to 120 °C (making the arithmetic mean secondary temperature (ΔT AM) 100 °C). Estimate the area of primary steam coil required., Actual Line Temp - Sat Temp = Total Superheat. 55°F - 37°F = 18°F. 18°F of Total Superheat > 9°F Target Superheat = Undercharged. Since the actual total superheat measured is higher than the target superheat, we would need to add refrigerant a little at a time until the superheat is the same as the target superheat., We use gauges and a temperature probe to measure subcooling, just like when measuring superheat. 2. We check the temperature of the liquid line near the condenser coil. 3. We'll check the head pressure at the condenser, comparing the readings to the manufacturer's standard. 4. Then we subtract the two numbers to calculate subcooling., Superheat, a term often thrown around in the realms of thermodynamics and HVAC systems, holds the key to unlocking the full potential of temperature control. In this guide, we will unravel the mysteries of superheat, providing you with a detailed understanding, practical insights, and expert recommendations. ... Breaking down the formula for ..., HVAC School has some handy calculators to help with various HVAC/R field tasks, including recovery tank fill and more. Superheat & Delta T Calculate target superheat for fixed metering device (piston) systems and air split on 400 CFM per ton A/C, By keeping track of superheat, HVAC professionals can ensure that the refrigerant is neither overheating or damaging the compressor overall. Superheat can ultimately tell a homeowner a lot about their HVAC system. For example, a superheat that is too high might indicate the refrigerant is overcharging. If it is too low, it may mean the ..., Design Temperature Difference (DTD) In air conditioning applications, a 35°F DTD is a good guideline for systems that run 400 CFM (679.6 m 3 /h) of air per ton of cooling (12,000 BTU/hr). In refrigeration, the DTD is much lower than in air conditioning. There are several reasons for this, but one big reason is the desire to maintain relatively ..., 4. When ambient air temp (Outside air temp) is 75-85 degrees the superheat should be 12-15 degrees, if the ambient temperature is 85 degrees or over the superheat should be 8-12 degrees. 5. If superheat is low then flooding the evaporator. Note: Do not adjust charge yet. 6. If superheat is high then starving the evaporator. Note: Do not adjust ..., Superheat and Subcooling are technical readings in an HVAC that measure the Freon (refrigerant) reading. Superheat measures the Freon boiling point in gas form while subcooling measures the Freon in liquid form below the evaporation level. To calculate superheat and subcooling measurements, a specific Mathematical chart is used, and the process ... , November 2, 2003. Several major manufacturers are producing comfort air conditioning equipment using refrigerant 410A. The trend towards the use of R-410A continues to grow and there is a demand for technicians who are comfortable working with this higher-pressure replacement for refrigerant 22. Due to the differences between R-22 and the newer ..., For this example the Liquid line Temp is 95 degrees. Subtract the Liquid line Temperature from the Liquid Saturation Temperature and you get a Subcooling of 15. “Typically” on TXV systems the Superheat will range between 8 to 28 degrees with a target of about 10 to 15 degrees. The Subcool range on TXV systems will range from about 8 to 20. , Good Subcooling Value for R-410A: Similar to superheat, the ideal subcooling value for R-410A can vary depending on factors like system design and operating conditions. However, a common target for R-410A systems is to achieve a subcooling value in the range of 8 to 15 degrees Fahrenheit (°F) or approximately 4.4 to 8.3 degrees Celsius (°C)., Our 300 question HVAC practice test provides: A 100 question EPA 608 practice test comes with our materials. Take this free HVAC practice test to see how prepared you are for an HVAC certification exam. 1. a. Open area of wall and low to the ground. b. Behind appliances and high on the wall. c. Open area of wall and high on the wall., Watch on. You can find your target superheat using charts, such as manufacturer-provided ones or universal ones from sources like TruTech Tools or the HVAC School app. You need the outdoor dry-bulb temperature and the indoor wet-bulb temperature; the indoor wet-bulb temperature gives you a better idea of the total indoor …, Fixed metering device- If an air conditioning system contains a fixed metering device, such as a piston, the correct method of evaluating refrigerant charge is superheat. ... Now use the following formula to determine superheat: Suction Line Temp - Evaporator Saturation Temp = Superheat As an example, if the suction line temperature is 59 ..., 13 Dec 2016 ... Do not try this at home! HVAC training is required! Working Joe's Website - http://workingjoesroundtable.com/ Facebook Page ..., Superheat target calculation hvac. Patent us8583384Target superheat calculation for hvac Ton 410 carrier temperature split hvac readings mr 2010 working am system hi name est pearson jeff edited outsideSuperheat chart. Patent us8583384How to check superheat 410a Chart superheat charging 410a heat pump pressure r410a ac target diagram charge ..., Another quality work from Superheat Electrical and Air-conditioning.#heatingandcooling #hvac #heating #COOLING #ventilation #Heating #heatpumps #hvacrepair #hvacmaintenance #hvactechnician #hvacinstall #hvacservice #airconditioning #hvaccontractor #hvaclife #cool #fypシ #fypシ゚viralシ #waikato #newzealand #hamiltonnz, The working conditions are: condenser and evaporator pressures of 7.2 bar and 2.2 bar respectively, R-12 used as a refrigerant and superheating of 10 ℃. The analytical comparison shows the way to give the preference to such superheating under the working conditions mention above. Download Free PDF. View PDF., Superheat = Current Temperature – Boiling Point. Superheat is measured by its temperature above its boiling point. If a refrigerant vapor boiling point is 140 degrees, for example, then anything about that pressure would be too high for that specific refrigerant. To calculate the measurement of subcooling, the formula is: Subcooling = Boiling ..., By Bryan Orr. July 27, 2020. Share this Tech Tip: The most common—and often most frustrating—questions that trainers and senior techs get asked sound something like …, Looking to determine what the target superheat formula is but don't have the manufacturer's charging chart? Find out how in this edition of HVAC Skill Builder,…, Yes, it is recommended by Copeland. "Another method to determine if liquid refrigerant is returning to the compressor is to accurately measure the temperature difference between the compressor oil crankcase and the suction line. During continuous operation we recommend that this difference be a minimum of 50°F (27°C).