2024 Head pressure hvac

Apr 17, 2022 ... HVACR Service Call: Water Source Refrigerator With High Head Pressure Tripping On Pressure Control. Jumper man Tech•6.1K views · 11:06. Go to .... Psa 308 sabre

Physical Properties Of R22. In parallel to using the R22 PT chart, professionals will usually need to know some of the following R22 physical properties: R22 liquid density at -69°C: 1.49 g/cm 3. R22 gas density at 15°C: 3.66 kg/m 3. Triple point temperature: -115.76K. Critical pressure: 49.36 bar. Heat capacity ratio at 86°F: 1.178253.Bryan with HVAC School goes over AC pressures, subcooling, and superheat in his troubleshooting mindset presentation from the BTrained HVAC training event in Birmingham, AL. Bryan also talks a bit about his educational photo-sharing app, MechPic. The suction pressure and suction saturation give us an idea of the refrigerant’s boiling …Suction fluctuating pressure was 70 - 74 PSIG. Fluctuation is immediately following start up. Superheat was low about 7F. Subcooling was high like 35F. My first impression was maybe it was overcharged so I recovered about 1 and 1/2 pounds. It brought the head pressure down to a fluctuation of 195 -> 225. Suction pressure to 69 …Head pressure is the pressure generated by the gas compressor of your air conditioning system. It can be high or low depending on various factors, such a…Head pressure is a measure of the gas pressure in your AC system. Learn what causes high head pressure, how it affects your AC performance and how to fix it with professional help.Suction pressure and head pressure are directly proportional, and compression ratios remain close to constant roughly 3 to 1 for older A/C systems. So with 60# suction or 75 psia at 3 to 1 compression you get 225 psia head pressure, raise that return temp and get suction pressure up to 85# or 100 psia you get 300 psia.Dec 5, 2020 ... HPCV/ head pressure control valve / head ... D2D NY Real World HVAC Simplified. 16.2K ... HVACR Service Call: Water Source Refrigerator With High ...The high side guage was connected to the liquid line. Static, both guages are 160 psig. When the unit ran, BOTH guages dropped to about 130. The high side was perhaps 2-5 higher. The amp draw at the compressor was 8.6 RLA out of a 22.1 suggest maximum on the equipment sticker.The fan speed controller keeps the condensing pressure at a steady level by regulating the speed of the fan motors. When pressure is declining, the controller decreases the output voltage, changing the speed of fan motor. The proportional band is a non-adjustable pressure difference between max. and min. pressure where the regulation occurs ...Apr 17, 2022 ... HVACR Service Call: Water Source Refrigerator With High Head Pressure Tripping On Pressure Control. Jumper man Tech•6.1K views · 11:06. Go to ...In conclusion, the Head Pressure Calculator presented here offers a reliable tool for quick and accurate calculations. Whether you’re dealing with fluid dynamics, HVAC systems, or plumbing, this calculator simplifies the process. By understanding the formula, utilizing the example, and referring to the FAQs, users can confidently use this ...Head-Pressure Control Valves Operation. The ORI head pressure-control valve is an inlet pressure regulating valve. It responds to changes in condensing pressure only. The valve designation stands for opens on rise of inlet pressure. As shown in Fig. 11-32, the outlet pressure is exerted on the underside of the bellows and on top of the seat …Mar 10, 2014 · This video explains what determines head pressure in refrigeration systems. Its explained by a Dunwoody College of Technology staff member Tom Kleinman. 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... Various experts and professionals claim that head pressure for a 410A system should be 400 to 418 PSIG on the high side while 120 to 130 PSI on the lower side. Anything more than this range is considered high head pressure. This value may vary a little bit depending on the weather and other external conditions. Pressure in the head and neck. The stress in the nerves and muscles of the neck can cause pain in the head. Sometimes, pressure or pain appears in both the head and the neck. This can be caused by ...R410a min. head pressure. before i ask let me say i am certified in R410a and i work with it almost everyday so please keep that in mind. i was always taught that if it was below 65 oat you have to keep a min. head pressure. what is a min head pressure for 410a? Reply. 02-15-2009, 05:31 PM #2.Low suction pressure and high head pressure is a condition where there is a decreased refrigerant pressure in the AC system and at the same time a high output pressure in a compressor. This condition is mainly caused by a …Low suction pressure and high head pressure is a condition where there is a decreased refrigerant pressure in the AC system and at the same time a high output pressure in a compressor. This condition is mainly caused by a defective or malfunctioning TXV valve. An expansion valve is a device that regulates the flow of the liquid refrigerant into ...Feb 6, 2013 · If you are wanting to maintain 180 psig. head pressure the controls would be set as follows: Cut-in Cut-out. Fans 1-2 180 psig. 160 psig. Fans 2-4 200 psig 190 psig. As you can see, this causes fluctuation of the head pressure and can result in expansion valve hunting and poor superheat control. HVAC Static Pressure - Main Duct Must Reduce in Size. HVAC static pressure is maintained in your home by making the main supply duct get smaller the farther away it is from the furnace. Tim Carter. HVAC static pressure needs to be maintained equally in all ducts for you to be comfortable in your home. Lennox Learning Solutions teaches you what causes high head pressure on a heat pump in the heating mode.There is several factors that can cause hight pressur...Bryan with HVAC School goes over AC pressures, subcooling, and superheat in his troubleshooting mindset presentation from the BTrained HVAC training event in...During air conditioning mode, the pressure on the vapor line of an R-410A system will be somewhere between 102 to 145 PSIG. If the system had R-22, the vapor pressure would be between 58 to 85 PSIG but these pressures will be dependent on the wet bulb temperature inside the building and the ambient temperature outside the …condenser cycles off, the water regulating valve should. Click the card to flip 👆. a. remain open during the off cycle. b. close, since the head pressure is lower. c. open all the way to remove any residual heat. d. re-calibrate itself to maintain the new lower head pressure. ANSWER :B. Click the card to flip 👆.Make your influence uniquely far-reaching. If they pulled a vacuum period, and broke the vacuum with R22, then the problem isn't noncondensables. There simply wouldn't be enough air or nitrogen in the system even at 28-29" vacuum to affect the head pressure. The high head pressure is more likely due to an overcharge.Totalineﬁ Head Pressure Controls The Totalineﬁ P251-0083C Solid State Head Pressure Control Designed specifically for HVAC and Refrigeration applications, the P251-0083C is a temperature-sensitive fan motor speed control which regulates head pressure at low ambients by varying the air volume through the condenser. Its unique constructionHead just surging from 280 t0 330 about every 10 to 15 seconds. Talking with owner had Company X out on a service contract, he signed up on a year prior. Guess his system was freezing up and tech wrote down he found leak at schraeder core on LL valve. Replaced schraeder and added 2 pound and 3 ounces of NU22. Undercharged. Can lead to low head pressure. Overcharged. Can lead to high head pressure. Understanding Overcharged Systems When too much refrigerant is crammed into your AC system, a few detrimental things happen: Excess Liquid: Overcharged systems usually have an excess of liquid refrigerant flowing into the compressor. Head pressure in HVAC refers to the force that keeps refrigerant flowing smoothly through the system. It is essential for optimizing performance and energy efficiency. Understanding head pressure is crucial for troubleshooting and resolving issues that affect system stability.If you are wanting to maintain 180 psig. head pressure the controls would be set as follows: Cut-in Cut-out. Fans 1-2 180 psig. 160 psig. Fans 2-4 200 psig 190 psig. As you can see, this causes fluctuation of the head pressure and can result in expansion valve hunting and poor superheat control.Came across another Rheem recently with a high head pressure in heat mode. Its a RPPL. Head pressure slowly climbs to above 600, suction pressure is normal not low at all. Airflow inside is okay... static pressure is .7inWc. Coils are clean. In cooling mode the charge looks damn near perfect... 11 degrees subcooling and 9-11 degrees superheat.What exactly is head pressure in an HVAC system? Head pressure, also known as high-side pressure, is the force that the compressor in your HVAC system uses to push refrigerant through the cooling cycle. It’s crucial for efficient operation.Suction Pressure: 65 PSIG (roughly 10 degrees) Discharge Pressure: 205 PSIG (roughly 72 degrees) Suction temp: 61 F Discharge temp: 64 Superheat: 51 F Subcool: 8 F Trane R410A system has a design subcool of 10 +/- 3 degrees so my subcooling is within the threshold.Head pressure in HVAC systems is a critical factor for efficient operation, reflecting the pressure at which the refrigerant is condensed into a liquid. Properly managing head pressure ensures the longevity and efficiency of your HVAC system, reducing the likelihood of breakdowns and energy waste.condenser cycles off, the water regulating valve should. Click the card to flip 👆. a. remain open during the off cycle. b. close, since the head pressure is lower. c. open all the way to remove any residual heat. d. re-calibrate itself to maintain the new lower head pressure. ANSWER :B. Click the card to flip 👆.Fluctuating head pressure, R22, Piston. Looks like non condensables. Noncondensibles for sure, possibly moisture. -Recover all refrigerant. -If you can change the oil in the compressor might be worth it. -Replace Filter drier. -Triple evac If you have the time. -Charge by weight, then check superheat and add what’s needed.Bryan with HVAC School goes over AC pressures, subcooling, and superheat in his troubleshooting mindset presentation from the BTrained HVAC training event in Birmingham, AL. Bryan also talks a bit about his educational photo-sharing app, MechPic. The suction pressure and suction saturation give us an idea of the refrigerant’s boiling temperature.Watch on. Compression ratio is the ratio of head pressure to suction pressure in an HVAC/R unit. Generally, compression ratios approach 2.5:1 on high-efficiency, 16+ SEER A/C systems. The highest compression ratio in A/C compressors is typically 11:1. Refrigeration compression ratios tend to be quite a bit higher (up to 26:1).Mar 10, 2014 · This video explains what determines head pressure in refrigeration systems. Its explained by a Dunwoody College of Technology staff member Tom Kleinman. February 8, 2024by J & J Services. Static pressure in HVAC systems is the resistance to airflow within the ductwork, which is crucial for maintaining system efficiency and preventing issues such as uneven heating/cooling and increased energy costs. Table of Contents. Effects of Static Pressure on HVAC System Performance.In this HVAC Training Video, I show the R-22 and R-410A Range of Operating Pressures on Air Conditioning Systems! I show why we Measure Pressures and Tempera...Low suction pressure and high head pressure is a condition where there is a decreased refrigerant pressure in the AC system and at the same time a high output pressure in a compressor. This condition is mainly caused by a defective or malfunctioning TXV valve. An expansion valve is a device that regulates the flow of the liquid refrigerant …When the temperature and pressure of the bulb’s charge rises, the powerhead provides the force to open the TXV. When the temperature and pressure of the bulb charge decreases, the TXV closes. As you can see, the sensing bulb determines if a TXV opens or closes. The powerhead is simply there to relay the pressure from the bulb and provide the ...Nov 9, 2018 · The most common liquid line restrictions are clogged filter-driers, metering device inlet screens, a kinked liquid line, or a TXV with an empty bulb. These very rarely cause high head for more than a short period of time. The most common causes of high head pressure include high load, overcharge, and poor heat rejection (such as from dirty or ... Here are some of the symptoms of this system: • Higher than normal discharge temperatures; • Low condensing (head) pressures and temperatures; • Normal to high condenser subcooling; • Normal to high superheats; • High evaporator (suction) pressures; and. • Low amp draw. Higher than normal discharge temperatures:A discharge valve ...head pressure will result in low suction pressure and/or iced evaporator coils. The primary off-cycle problem is the possible inability to get the system on-line if the refrigerant has migrated to the condenser. The evaporator pressure may not build up to the cut-in point of the low pressure control and the compressor can’t start even though refrigeration is …Low Ambient, Condenser Flooding, and Headmaster Valves. In this podcast episode, Jeremy Smith comes on the podcast to talk about low-ambient controls, headmaster valves, charging, and condenser flooding. If our head pressure drops too much, we won't get enough of a pressure drop across the TXV. Pressures dictate the TXV function, so we …A thermostatic expansion valve (TXV) (see Figure 1) is a refrigeration and air conditioning throttling device that controls the amount of refrigerant liquid injected into a system’s evaporator—based on the …Head pressure, also known as high-side pressure, is the force that a HVAC compressor generates to move refrigerant through the system. Why is head pressure significant in an HVAC system? Proper head pressure ensures efficient operation and cooling performance of your HVAC unit.Understanding Head Pressure in HVAC Systems Force Exertion. Head pressure in an HVAC system is the force that refrigerant exerts within the compressor. It’s a key player in moving refrigerant through the system, including head pressure controls. Think of it as pushing a fluid through a pipe at home; more pressure control means faster movement.With your HVAC unit’s head pressure, there are two that are more common than the rest: high head pressure and low head pressure. High Head Pressure. High head pressure is typically accompanied by a low suction pressure. This combination can be indicative of restricted refrigerant.Helps prevent evaporator freeze-ups, liquid-slugged compressors, low pressure cutouts and overshoots seen with on/off & pressure switch controls. Mode of Operation ICM Head Pressure Controls operate as temperature-sensitive motor fan speed controls. Head pressure is regulated during ... Air Conditioning and Heat Pumps ICM326HN Typical ...When it comes to purchasing an HVAC system, one of the most well-known brands is Lennox. However, you may have noticed that prices for Lennox systems can vary greatly depending on ...Pump head pressure basics, learn why pumps read pressure in height and call it head pressure.Learn more here ️ https://theengineeringmindset.com/pump-head-...In fluid mechanics, pressure head is the height of a liquid column that corresponds to a particular pressure exerted by the liquid column on the base of its container. It may also be called static pressure head or simply static head (but not static head pressure). Mathematically this is expressed as: = = where is pressure head (which is actually a …Gonzo, if your evap was dirty you would have a low suction and low superheat. Not dirty evap let that go. High suction low head, with 100 lb suc and 100 degree ambient your head should be quite a bit higher. Really need the amp draw of comp and rated RLA but appears to be a compressor issue.An HVAC technician taking a static pressure measurement. STEP 2: Drill test ports using a 3/8′ drill bit with a metal piercing tip. A bullet-tip drill makes a clean round port. So make sure to use your drill bit sheath (described above) to help prevent you from drilling into the coil.Today customer claims Liebert mini-mate has been locking out on high head pressure once or twice a month, sometimes more often, since it was installed approx. 1 year ago. The company that installed it has come out several times to check it out but found no high pressures. I decided to take the high pressure control out of the picture and …Jun 11, 2021 · Head pressure is also sometimes referred to as discharge pressure or high side pressure. The output side of the compressor in an HVAC unit generates this pressure, and it can be affected by many variables. For instance, the condenser fan’s size and speed can play into the head pressure, as can the condenser coil’s overall condition and how ... There are three main reasons why a reciprocating compressor will simultaneously have a low head pressure and a high suction pressure. • Bad (leaky) compressor valves; • Worn compressor piston rings; and. • Leaky oil separator return line. LEAKY COMPRESSOR VALVES.To replace a defective low-ambient control valve with a pressurized dome charge, follow the steps below: 1. Recover the refrigeration system’s refrigerant; 2. Cut the process tube on the valve’s charged dome to remove the pressure charge (wear safety glasses); 3. With a torch, heat the valve until the solder melts; 4.HVAC Static Pressure - Main Duct Must Reduce in Size. HVAC static pressure is maintained in your home by making the main supply duct get smaller the farther away it is from the furnace. Tim Carter. HVAC static pressure needs to be maintained equally in all ducts for you to be comfortable in your home.Very high suctuion and head pressure on heating mode. Hello, I have a Rheem (2015) heat pump 2ton 410A, on cooling mode the system runs great; suction and liquid pressure are ok 185/360, super heat 10 F, with 90F outdoor temperature, now the winter is coming and the system on heating mode the gages read high pressure on both …I was working on a water source heat pump Trane serial number# W04C11546 MN# GEVB02411J0110TL. The unit is an upflow with the compressor compartment being on the bottom and the fan and coil on top. The problem is that the unit will run for about one minute in cooling mode then goes off on high head (400 psi r-22). Unit runs fine in heat.Three indications that your HVAC system make have high static pressure are: Uneven Heating and Cooling. Higher Energy Bills. A Noisy System. Before we go any further, we’ll note that these symptoms aren’t exclusive to this problem. But, if you’re noticing all three, then this could be what’s causing them.Took a reading off one of our units that cool an elevator machine room. It's an old Carrier 10 ton unit, single compressor, water cooled tube in tube condenser. Suction pressure was good at 68 , head pressure went over 300 and was tripping it out. Cleaned the strainer, same thing happens. Brought in a mechanic who says the TEV is bad and …0.1 Understanding HVAC Pressure; 0.2 Common Causes of High Head Pressure; 0.3 Refrigerant what causes high head pressure hvac? 0.4 Dirty Condenser Coils; 0.5 Restricted what causes high head pressure hvac; 0.6 Faulty Condenser Fan Motor; 0.7 Non-condensables in the System; 0.8 Diagnosing High Head Pressure; 0.9 Preventing High Head PressureSingle Package Air Conditioner and Heat Pumps ... The Head Pressure Control Kit is designed for use in the ... pressure switch opens when the head pressure rises ...What exactly is head pressure in an HVAC system? Head pressure, also known as high-side pressure, is the force that the compressor in your HVAC system uses to push refrigerant through the cooling cycle. It’s crucial for efficient operation.Head pressure is essential to the proper operation of your HVAC system because it helps maintain the refrigerant in a liquid state. If the head pressure is too low, it can indicate problems like insufficient airflow or refrigerant charge, which can lead to poor cooling efficiency. Conversely, if the head pressure is too high, it can mean issues ...Dec 5, 2020 ... HPCV/ head pressure control valve / head ... D2D NY Real World HVAC Simplified. 16.2K ... HVACR Service Call: Water Source Refrigerator With High ...Optimised Head Pressure Control. A unique controls feature available to Chiller, Precision and Data Centre DX products, Optimised Head Pressure Control offers substantial energy savings. In HVAC systems, head pressure is typically controlled during low ambient conditions by varying the amount of airflow through the condenser in order to prevent ...Lennox Learning Solutions teaches you what causes high head pressure on a heat pump in the heating mode.There is several factors that can cause hight pressur...6 days ago ... Head Pressure Control Valve Operation in Commercial Refrigeration #technology #cool #hvac #training hvac training, hvac training videos, ...Typical Low Side Pressure Range for R410A in the field: 115-120 psi. Typical High Side Pressure Range for R410A in the field: 410-420 psi. By 2025, high Global Warming Potential (GWP) refrigerants with a GWP of over 750, will be banned together with the systems using that gas. R410A has a GWP > 2,000. Various experts and professionals claim that head pressure for a 410A system should be 400 to 418 PSIG on the high side while 120 to 130 PSI on the lower side. Anything more than this range is considered high head pressure. This value may vary a little bit depending on the weather and other external conditions. Head pressure is a critical factor in HVAC (Heating, Ventilation, and Air Conditioning) systems. It refers to the pressure exerted by the refrigerant in the condenser coil, and it is measured in pounds per square inch (PSI).Head just surging from 280 t0 330 about every 10 to 15 seconds. Talking with owner had Company X out on a service contract, he signed up on a year prior. Guess his system was freezing up and tech wrote down he found leak at schraeder core on LL valve. Replaced schraeder and added 2 pound and 3 ounces of NU22.OPERATING PRESSURE POINTS “Systems using R-410A operate at higher pressures [than R-22],” points out the Field Diagnostics team. “For example, to produce an evaporating temperature of 40 degrees F and a condensing temperature of 115 degrees, the suction and head pressures would be 83 psia and 257 psia in an R-22 … Fan cycling is the easiest and cheapest way to maintain a minimum head pressure. By using a close on rise pressure control we can successfully cycle the condenser fan on or off to maintain head pressure. Fan cycling controls can be adjustable or non-adjustable. The non-adjustable fan cycling controls are selected by the pressure settings ... During air conditioning mode, the pressure on the vapor line of an R-410A system will be somewhere between 102 to 145 PSIG. If the system had R-22, the vapor pressure would be between 58 to 85 PSIG but these pressures will be dependent on the wet bulb temperature inside the building and the ambient temperature outside the building.The warmer it is outside, the higher the pressure will be. For a general reference, you can check out this chart of R-134a system pressures. If you find you’ve got a low pressure on the low side of your system, then it’s most likely that you’ve got a leak as that is a common problem in automobile air conditioning systems.

Oct 29, 2004 · A 30 degree reduction in condensing temperature (110 degrees to 80 degrees) will reduce the current draw to 37.5 amps. While a 6.75-percent reduction is significant, it's only part of the story. The typical supermarket compressor rack will run a reasonably constant suction pressure, regardless of head pressure. . Road closings nashville tn

Understanding Head Pressure in HVAC Systems Force Exertion. Head pressure in an HVAC system is the force that refrigerant exerts within the compressor. It’s a key player in moving refrigerant through the system, including head pressure controls. Think of it as pushing a fluid through a pipe at home; more pressure control means faster movement.Nov 9, 2018 · The most common liquid line restrictions are clogged filter-driers, metering device inlet screens, a kinked liquid line, or a TXV with an empty bulb. These very rarely cause high head for more than a short period of time. The most common causes of high head pressure include high load, overcharge, and poor heat rejection (such as from dirty or ... Caffeine intake, nicotine, exercise, stress, fever and medication can all cause the palpitations that result in you feeling your own heartbeat in your head, according to MedlinePlu...Sep 9, 2021 · The pressure created on the output side of a gas compressor in a refrigeration or air conditioning system is known as discharge pressure. It is also known as high side pressure or head pressure. A refrigerant restriction indicates an extraordinarily high discharge pressure combined with an external suction pressure. Suction Pressure: 65 PSIG (roughly 10 degrees) Discharge Pressure: 205 PSIG (roughly 72 degrees) Suction temp: 61 F Discharge temp: 64 Superheat: 51 F Subcool: 8 F Trane R410A system has a design subcool of 10 +/- 3 degrees so my subcooling is within the threshold.Low-side (evaporator) pressure - 3.94 inches Hg (minus 20°F) High-side (condensing) pressure - 86.4 psig (80°F) Calculated Values: Condenser split - 10°F; Condenser subcooling - 2°F; Evaporator superheat - 30°F; Compressor superheat - 70°F; Since the evaporator is starved of refrigerant from the undercharge, there will be high …Oct 29, 2004 · A 30 degree reduction in condensing temperature (110 degrees to 80 degrees) will reduce the current draw to 37.5 amps. While a 6.75-percent reduction is significant, it's only part of the story. The typical supermarket compressor rack will run a reasonably constant suction pressure, regardless of head pressure. Take two flat head screwdrivers, carefully put one one each side under the spring on the water reg valve, and lift the spring up for 20-30 seconds. If there is any junk stuck in the valve the water flow may flush it out and get it going for now. Sent from my SGH-I747M using Tapatalk. Reply. 04-15-2014, 01:55 PM #6.On 2019-01-24 by Rkg1963 - Nordyne heat pump head pressure shuts the system down at 600 in heat mode. Have a 3 ton Nordyne Residential HeatPump Condenser that the head pressure run up around 600 before it shuts down . Only in Heat mode. Pressures look great in Cool mode. Any ideas as to why this is? On 2017-11-01 by DavidThe two most common causes of low head pressure at an air conditioner or heat pump compressor motor are: Refrigerant under-charge, due to a refrigerant leak or improper charge. TXV (TEV) malfunction, over-metering refrigerant. This condition is not likely to occur on smaller air conditioners or heat pumps that use a capillary tube to meter ...The pressure created on the output side of a gas compressor in a refrigeration or air conditioning system is known as discharge pressure. It is also known as high side pressure or head pressure. A refrigerant restriction indicates an extraordinarily high discharge pressure combined with an external suction pressure.Dec 5, 2020 ... HPCV/ head pressure control valve / head ... D2D NY Real World HVAC Simplified. 16.2K ... HVACR Service Call: Water Source Refrigerator With High ... The fan speed controller keeps the condensing pressure at a steady level by regulating the speed of the fan motors. When pressure is declining, the controller decreases the output voltage, changing the speed of fan motor. The proportional band is a non-adjustable pressure difference between max. and min. pressure where the regulation occurs ... Head-Pressure Control Valves Operation. The ORI head pressure-control valve is an inlet pressure regulating valve. It responds to changes in condensing pressure only. The valve designation stands for opens on rise of inlet pressure. As shown in Fig. 11-32, the outlet pressure is exerted on the underside of the bellows and on top of the seat …February 8, 2024by J & J Services. Static pressure in HVAC systems is the resistance to airflow within the ductwork, which is crucial for maintaining system efficiency and preventing issues such as uneven heating/cooling and increased energy costs. Table of Contents. Effects of Static Pressure on HVAC System Performance.May 25, 2017 ... In this HVAC Video, I go over how to Calculate a Refrigerant Charge on an Air Conditioning Condenser by Measuring Temperature and Pressure ....

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