Hvac superheat formula

Quick Tip #9: Superheating and Subcooling. Fully understanding superheat and subcooling is the key to a refrigeration system performing at its optimum level. Closed captioning is available for this video. To activate this feature, play the video and then select "English" from the menu (CC icon) in the upper left corner of the video player ...

Hvac superheat formula. Chw in 49.8/out 44.0./. Evap refr 41.8/ CDw in 77/out82.8/ cond temp 87.0 /oil press. 24.3/ temp.132.7/ amps80.9%. If your oil sump level is low and the chiller is tripping on low discharge superheat, it is likely the oil is in the evap and carrying over resulting in this fault.

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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.The maximum recommended temperature is often around 150 to 160 degrees Fahrenheit (65.6 to 71.1°C) for the condenser coil. What is normal subcooling for 410A? Normal subcooling for R-410A systems can range from 10 to 20 degrees Fahrenheit (5.6 to 11.1°C) depending on the specific system design and conditions.Superheat and subcooling ... Superheat is just one component of the refrigerant charging equation ... High-Performance HVAC Today, Copyright © 2024 National Comfort ...The formula to calculate superheat uses the current temperature and boiling point. Superheat = Current Temperature – Boiling Point. In this example, the superheat is 10-degrees. Superheat is critical in HVAC …145 °F. 571.7 psig. 150 °F. 607.6 psig. 155 °F. 645.2 psig. You can see that this R410A pressure chart includes high and low side pressures at temperatures ranging from -60 °F to 155 °F. Higher temperature equates to higher pressure. Here are 4 examples of how you can use this chart:Chw in 49.8/out 44.0./. Evap refr 41.8/ CDw in 77/out82.8/ cond temp 87.0 /oil press. 24.3/ temp.132.7/ amps80.9%. If your oil sump level is low and the chiller is tripping on low discharge superheat, it is likely the oil is in the evap and carrying over resulting in this fault.

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 ... For example, the temperature in the return duct may read 72°F (T1) while the temperature at the supply may be 53°F (T2). In this case, 72°F (T1) - 53°F (T2) = 19°F therefore Delta T (ΔT) = 19°F. You can write this as ΔT = 19°F or Delta T = 19°F and either would both be correct. At this point, we have covered how to find the Delta T ...Welcome to HVAC-Talk.com, a non-DIY site and the ultimate Source for HVAC Information & Knowledge Sharing for the industry professional! ... LTMD please elaborate on superheat formula. Old system with no chart, I go 10 - 15* for 80* to 90* ambient. 5* to 10* superheat for 90 to 100* ambient, thats once indoors has reached …You will need a psychrometer, a target superheat calculator (such as on hvacrschool.com or the HVAC School app), and a manufacturer target superheat chart; measureQuick can help you take these measurements. Once you know your target superheat, you can set the charge accordingly. A common rule of thumb is to achieve a 10-degree target superheat ...In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to check the refrigerant charge, and show where the measurement points are taken on an air conditioning system. Total Superheat Formula: Actual Vapor Line Temp - Sat Temp = Total Superheat So what does this mean ...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.Evaporating. R452A, operating with suction pressure of 1.5barg, has a bubble point temperature of -26.27°C and a dew point temperature of -22.37°C. This means the first part of the refrigerant composition starts to evaporate at -26.27°C. The first vapour bubble forms at -26.27°C, and as it continues to absorb energy, the refrigerant ...

Jan 5, 2024 · Understanding Superheat: The Perfect Formula. How Superheat is Calculated: Superheat is a crucial parameter in refrigeration and air conditioning systems. It represents the temperature difference between the vapor’s actual temperature and its saturation temperature at a given pressure. The formula for calculating superheat is: Con frecuencia se refiere al sobrecalentamiento como el "pulso" de la válvula de termo expansión. El sobrecalentamiento es importante para evaluar el funcionamiento de una válvula, sobre todo, para hacer un buen diagnóstico cuando se sospecha que la válvula es la que está fallando.SEC Superheat Control Kit. SEC Superheat Control Kit for LPF Electric Expansion Valve includes an SEC613-R4 controller and components to complete an EEV installation. With a few components on your truck, you can replace thousands of TXV variations. LPF Electric Expansion Valves can be purchased separately.Do not try this at home! HVAC training is required!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 ...

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Nov 21, 2023 · 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. Subtract the saturation (or dew point) temperature from the actual line temperature to get your superheat (temperature gained above the boiling point) at that point of the system. In order for this process to work at all, you need: An accurate, calibrated pressure gauge. An accurate, calibrated thermometer.A 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 ...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...To determine the Target Superheat for an air conditioning system with a fixed orifice (such as a piston or capillary tube) measure the indoor WB (wet bulb) temperature with a digital psychrometer and the outdoor DB (dry bulb) temperature with a standard digital temperature reader. Input these temperatures in a superheat chart, calculation, app, or digital manifold set in order to determine the ...

How To Check Evaporator Superheat - it is very important for any HVAC and refrigeration technician performing service, maintenance or start ups to understand...When we use PT charts on refrigerants with glide, we must understand exactly what dew point and bubble point are. The dew point marks the first change from vapor to liquid, and the bubble point marks the first change from a liquid to vapor. In the case of a refrigerant like R-407C, the difference between dew and bubble point is significant.Superheat in HVAC refers to the temperature of refrigerant vapor above its saturation point in the evaporator. Ideal superheat is typically 10-15°F. Subcooling involves refrigerant liquid temperature below its saturation point at the condenser outlet. Normal subcooling is often 10-15°F. Both metrics help assess system efficiency and refrigerant state, but acceptable values can vary by ...So you got to take that wet bulb. You take the outdoor dry bulb in the shade not affected by radiant. You find that and then you charge to it. If your superheat is higher than your target, you add charge slowly and carefully. If your superheat is lower than your target, then you recover charge slowly and carefully.Subtract the two and you have 10 degrees of Superheat. SUBCOOL. The Saturation temperature for Subcooling is acquired from the high side gauge. In this example the Sat Temp is about 110 degrees. Next is to “Minus Liquid Line Temp”. The Liquid Line Temperature is also measured at the outlet of the condensing unit but now is measured …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.Superheat hunting is a cyclical fluctuation in suction superheat due to varying refrigerant flow rate in the system. Superheat hunting is the result of the expansion valve (see Figure 1) excessively opening and closing in an attempt to maintain a constant operating condition.By keeping an eye on both subcooling and superheating, you can optimize your refrigeration system’s efficiency, prolong its life, and minimize energy consumption. Navigating through this hub page, you have learned the importance of maintaining the ideal superheat range, as both high and low superheat can cause potential problems in your system.In superheat, the temperature plays a vital role in the system’s performance. The discharge temperature should be less than 225 ° F. If the temperature is increased more than 225 ° F, the system’s performance is decreased. Most of the compressors used in refrigeration and air conditioning can withstand temperatures up to 225 ° F.Table of Contents. What is superheat and why is it important. What does superheat tell you. What is Superheat and Subcooling HVAC. Superheat and subcooling formula. …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.

Superheat is a critical concept in HVAC systems, referring to the temperature increase of a vapor—specifically the refrigerant in HVAC systems—above its boiling point at a specific pressure. This is not merely a technical detail; it’s an essential part of how your heating and air conditioning systems function.

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.HVAC superheat measures the difference between the vaporized refrigerant’s temperature and its saturation temperature. The saturation point, or boiling point, describes when the liquid refrigerant turns to vapor. Saturation occurs when there is a high level of heat and moisture in the air. The evaporator coil turns this moisture into a gas ...If you’re considering a career in the heating, ventilation, and air conditioning (HVAC) industry, one important credential you should consider is the Environmental Protection Agenc...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 ...ADD refrigerant to DECREASE total superheat. REMOVE refrigerant to INCREASE total superheat. Allow approximately 10 to 15 minutes of operation after refrigerant has been added or removed to determine final superheat. Verify proper evaporator performance (temperature split) using page RD9 of the "NON TXV Charging Guide".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 ...Understanding Superheat: The Perfect Formula. How Superheat is Calculated: Superheat is a crucial parameter in refrigeration and air conditioning systems. It represents the temperature difference between the vapor’s actual temperature and its saturation temperature at a given pressure. The formula for calculating superheat is:In air conditioning applications, compression ratios of 2.3:1 to 3.5:1 are common, with ratios below 3:1 and above 2:1 as the standard for modern high-efficiency air conditioning equipment. In a 404a medium-temp refrigeration (cooler) ... Once all of the discharge superheat (sensible heat) is removed in the first part of the condenser coil, it ...

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The formula to calculate superheat uses the current temperature and boiling point. Superheat = Current Temperature – Boiling Point. In this example, the superheat is 10-degrees. Superheat is critical in HVAC because it ensures the liquid refrigerant is boiled off before it leaves the evaporator and heads to the compressor.This minimizes superheat horn area when using i-pentane. The superheat horn area is created by replacing the isothermal heat transfer process in the Carnot cycle with the isothermal heat transfer in the standard vapor compression refrigeration system cycle. The smaller superheat horn area leads to higher exergy efficiency [29].In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to check the refrigerant charge, and show where the measurement points are taken on an air conditioning system. Total Superheat Formula: Actual Vapor Line Temp - Sat Temp = Total Superheat So what does this mean ...Or download onto your own device. P-T Calculator. This comprehensive Pressure/Temperature calculation tool provides several unique features designed to make the HVAC/R technician's job easier. Available for iOS and Android devices: For more information, call 800-262-0012. or e-mail [email protected]. a) Most walk-in coolers and freezers use a TX valve to regulate the flow of refrigerant into the evaporator. If the superheat is low the TX valve will allow refrigerant to flow into the evaporator at a rate that exceeds the capacity of the evaporator and as a result liquid will enter the suction line.Dec 27, 2023 · 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 ... Adjust and optimize superheat in less than 15 minutes. TXV Superheat Tuner is now part of Ref Tools, the essential, all-in-one mobile app for air conditioning and refrigeration technicians. Ref Tools gives you access to the tools, guidance, support, and information you need—on the job and in the field.The “approach” simply refers to the temperature difference between the liquid line leaving the condenser and the air entering the condenser. If you take readings in both places, the liquid line will be …Superheat = Evaporator Outlet Temperature – Saturation Temperature at Evaporator Pressure. What is the best way to calculate superheat? The best way to …Turn the unit on and immediately off to check for proper spin up and listen for bearing noise and out-of-balance vibration as the fan coasts to a stop. Check for a solid mounting and visually check for bent fan blades. Lubricate the motor shaft to minimize shaft corrosion. Check for exposed or loose fan wires.14 hours ago ... ... hvaccharts. air 121 Unit 10 ... formula, superheat calculator (410a, r22, etc. ... · How To Check Superheat & Subcooling On An HVAC System ·. ….

Evaporator outlet temperature. 56°F. Condenser outlet temperature. 74°F. When dealing with refrigerant blends that have temperature glide, when the liquid refrigerant boils in the evaporator, the composition of the liquid and vapor phases are different. The liquid phase becomes richer in the higher boiling point component as the low boiling ...By keeping an eye on both subcooling and superheating, you can optimize your refrigeration system’s efficiency, prolong its life, and minimize energy consumption. Navigating through this hub page, you have learned the importance of maintaining the ideal superheat range, as both high and low superheat can cause potential problems in your system.Liquid line temp 101 degrees and the suction was 49 degrees. The low subcooling and low suction pressure indicate low airflow. The somewhat low deltaT seems to contradict that. Could be a significant amount of air bypassing the coil based on your report, which would account for all of the numbers that you posted.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.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 twoRobo stated it clear, the normal superheat for a residential system can and will vary and some charts go even further than he stated 2-45 degrees. That answer above drives the point, if you do not know the evaporator load, you can not predict the superheat. Reply. 06-02-2011, 06:58 PM #14. hvacvegas.Superheater - increases the steam temperature above the saturation temperature. Reheater - removes the moisture and increases steam temperature after a partial expansion. The superheating process is the only way to increase the peak temperature of the Rankine cycle (and to increase efficiency) without increasing the boiler pressure. This ...In short, high discharge temp can commonly be caused by: Low charge (high suction superheat, low suction pressure, low subcool) Severe overcharge. Low condenser airflow. Restricted metering devices. Other restrictions (liquid line drier, suction line drier, kinked lines, clogged screens) Low discharge line temp can be caused by.The figure on the following page shows the difference between 0 °F and 15 °F superheat. Point B is the 100% vapor point at a constant evaporator/suction ... Hvac superheat formula, Here's the step-by-step guide: Prior to subcooling measurement, the AC unit should be off for at least 30 minutes. This will equalize the refrigerant pressure throughout the unit (lines, coils) since the refrigerant is in a saturated state (mixture of vapor and liquid). Let the air out of the HVAC gauge. Open the vent, listen to that ..., 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..., Taking the measurements is useful for any type of system, to identify trouble spots. However, when charging a TXV system, you charge by subcooling. And, when charging a cap-tube system, you charge by superheat. Both types can be charged by weight, if known. Trust, but verify. RSES Certificate Member Specialist., 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)., This is something I always wondered when looking at a target superheat table, and no one I've asked has really had a good answer. Wet bulb temperature alone doesn't correspond to a unique enthalpy. However, I think most target superheat tables assume 50% relative humidity, and that assumption together with the wet bulb temperature does correspond to a unique enthalpy., Feb 3, 2022 · In superheat, the temperature plays a vital role in the system’s performance. The discharge temperature should be less than 225 ° F. If the temperature is increased more than 225 ° F, the system’s performance is decreased. Most of the compressors used in refrigeration and air conditioning can withstand temperatures up to 225 ° F. , Refrigerant GWP Chart For 61 Freons (R410A, R134A, R22, etc.) List of Low GWP Refrigerants: 69 Refrigerants Below 500 GWP; All 16 Refrigerant Types + Lists Of Refrigerants (HFC, HC, HO, etc.) Target Superheat Chart + Calculator, Formula, R22, 410A Examples; Generators. What Size Generator Do I Need? (Simple 3-Step Method + Calculator), 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., To find your target superheat, you’ll need to measure the wet-bulb temperature indoors and the outdoor temperature. Then, use a superheat chart or formula to get your magic number. Simple enough, right? Measuring Existing Superheat. Next, obtain the suction line temperature and read the suction pressure using your HVAC gauges., If you'd like to support the channel, you can do so by shopping for whatever you need on Amazon through this link, http://amzn.to/2lEadp4Dirty Maintenance Sh..., 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., In this HVAC Training Video, I Show How to Explain Subcooling and Total Superheat to an Apprentice. I Show Where the Measurements are Taken, Tips to Help You..., Jun 6, 2021 · SUPERHEAT HVAC FORMULA. The Superheat for an HVAC system is calculated as the temperature difference between the saturation temperature of the fluid and the actual temperature of the gas. The refrigerants which are used in the HVAC system often boil at temperatures lower than that of water. Suppose a refrigerant’s boiling temperature is -20 0 ... , Superheat and Sub-Cooling. Whenever an HVAC technician needs to add refrigerant to a system or adjust the charge the tech needs to know what superheat and/or sub-cooling is to properly ensure the refrigerant charge is correct. It is also important to have a pressure-temperature or PT Chart to properly read the pressures and temperatures., Oct 26, 2021 - In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to check the refrigerant charge, and show where the measurement points are taken on an air conditioning system. Total Superheat Formula: Actual Vapor Line Temp - Sat Temp = Total Superheat So what does this mean and what is the difference between ..., 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% vapor, Do not try this at home! HVAC training is required!, 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., HVAC Charts - Your Source for Heating & Air Conditioning Charts and Supplies. R-410a Superheat & Subcooling Calculator. This tool is used for charging cooling systems that use R-410a 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 ..., This can be seen by measuring the superheat. To measure evaporator superheat: Record the actual temperature at the TXV bulb with a probe. Record the evaporating pressure at the TXV bulb. (Low side gauge pressure) Convert the evaporating pressure to temperature by using a pressure/temperature comparator. Subtract the …, For more information regarding our HVAC Training please visit http://www.hvactrainingsolutions.net or call (904) 671-7144This is part of our Online HVAC Cert..., 2. HVAC superheat calculator. This app can be used to do the HVACR diagnostics and service. It can calculate the target superheat for fixed orifice expansion devices, superheat and sub-cooling for 26 refrigerants, airflow calculations, and psychrometric calculations to aid with field service HVACR equipment., Charging a A/C system by subcooling. Determine your target subcooling. This is usually displayed on the back of the nameplate, located on your condensing unit. If not, 10-15 degrees F will get you ballpark range. With the unit running, connect your high side refrigerant gauge, to the liquid line port, or fitting., The TXV controls superheat by controlling the flow of liquid refrigerant. As it does this, it also reduces refrigerant pressure. Liquid refrigerant enters the TXV under high pressure. As the flow of liquid refrigerant is reduced, its pressure drops. The refrigerant leaving the TXV is now a combination of low-pressure liquid and vapor., 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., Liquid line temp 101 degrees and the suction was 49 degrees. The low subcooling and low suction pressure indicate low airflow. The somewhat low deltaT seems to contradict that. Could be a significant amount of air bypassing the coil based on your report, which would account for all of the numbers that you posted., The best way to calculate Superheat and Sub-Cooling. An HVACR system with an expansion valve (TXV) must be charged by Sub-Cooling. A system with a fixed metering device must be charged by Superheat. , It's fairly simple and it'll really help. Low side saturation 30-40 degrees F lower than return. High side saturation 10-15 higher than ambient. Refer to manufacturer's charts for subcool. Most superheats are around 10-15 in resi, Goodman should tell you the superheat and Subcool if they are an adjustable Txv., It has a good table of contents. Subcool is basically telling you stack of refrigerant in the condenser. Higher subcool = more refrigerant stacking in condenser. It's telling you how many degrees below saturation the refrigerant is getting. Saturation temp minus line temp. Superheat is telling you the opposite in the evaporator., As we will see in the R-22 and R-410A examples at the end, target superheat for a system using R-22 and the target superheat for a system using R-410A (or any other refrigerant) are the same. Only the DB and WB temperatures determine the target superheat. Here is the formula we use to calculate superheat: Target Superheat = (3 × TWet Bulb ... , Posts. 1,165. Post Likes. superheat is the amount of heat above the refrigerants saturation point, check you pressure temp chart, learn it love it. r-22 system running 68.5 psi suction 40 degree saturation point add 15 degrees superheat suction line temp 55 degrees. sub-cool would be the opposite the amount of heat below its saturation point., Aug 29, 2016 · In this HVAC Video, I Explain Superheat and Subcooling in the Refrigeration Cycle to Understand the Operation Easier! I go over how to understand the importa... , Oct 15, 2019 · 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 load on the coil.