Low subcool high superheat

Step-by-Step Low Superheat High Subcooling Fixes. Once you’ve identified low superheat high subcooling imbalances in your refrigeration system using the diagnostic tools and equipment mentioned earlier, it’s time to take corrective action. Here’s a step-by-step process to help you address these issues effectively: 1. Ensure Safety …

A low delta T may also be an indicator of low charge. The telltale signs are a low condensing temperature, low evaporator temperature, low subcooling, and high superheat. To get the most accurate readings, you should ensure that there are NO airflow restrictions and that the Schrader cores have been depressed if you take your readings with gauges.Subcooling is a process that takes place inside of your condenser coil shortly before the refrigerant moves on to the evaporator coil. This article takes a closer look at the important role that subcooling plays in overall air conditioning efficiency. The Nature of Subcooling. Before getting to the specifics of subcooling, you should know what ...Superheat & Subcooling Tools. Sort By: 14766 Robinair -58° to 302° F Superheat Thermometer For 18560 18561 Valve Core Remover Installer. Provides a means of checking refrigerant temperature in the stream of gas. The most accurate method of testing gas temp is by sampling the liquid directly. Price $44.58. Add To Cart.Low subcool and low superheat??? HSSAT: 84 HSLT: 82 SC: 2 LSSAT:46 LSLT: 54 SH: 8 Target super heat of 15 Wet bulb 63 Outdoor temp 79 R-410A. Coins. 0 coins. Premium Powerups Explore Gaming. Valheim Genshin ...To measure liquid subcooling: 1. Attach your gauge manifold to the liquid line service port. If you use a quick-connect fitting on the end of your hose, make sure it’s a low-loss fitting. I’ve seen some quick-connect fittings that allow pressure loss, which can cause inaccuracies in the charging procedure.Welcome to Enertech University, online training by Enertech. Measuring subcooling and superheat is a critical diagnostic testing procedure when a unit is not...Ferguson HVAC is a national distributor of residential and commercial heating and cooling equipment, parts and supplies. HVAC contractors across the country rely on us for the best unitary and ductless equipment brands and for a wide-range of HVAC products including accessories, controls, air distribution supplies, and service and repair parts.

When changing the superheat setting on a TXV. Converts high-pressure high temperature liquid refrigerant in to low pressure low temperature mix of vapor and liquid. A metering device is a refrigerant circuit device that. More sub-cooling improves the efficiency and capacity of the system. Which of the following statements about metering devices ...How to measure SUPERHEAT and SUBCOOLING! HVAC/R Training Video.How to calculate SUPERHEAT and SUBCOOLING on your air conditioner or refrigerator? R22 R410a R...Low superheat high subcooling is a common issue with AC units. There are 5-6 low superheat causes and 3 high subcooling causes. By comparing these causes, we can see which ones are the reason we have low superheat and high subcooling. Here is a chart of low superheat causes (on the left) and high subcooling causes (on the right). The culprits ...Adjusting Superheat and Subcooling Values Troubleshooting high superheat. If your superheat value is too high, it might be due to issues like low refrigerant charge, dirty evaporator coils, or an incorrect metering device. It's like trying to find the cause of a flat tire - you need to inspect and fix the problem! Troubleshooting low superheatApr 22, 2024 · Many manufacturers recommend a subcooling range of 10° – 15°F, but always refer to manufacturer instructions to be sure. Just as there are two kinds of superheat, there are also two kinds of subcooling. They are condenser subcooling and total subcooling. We usually measure subcooling at the liquid line service valve. High suction pressure. One sign of low subcooling is high suction pressure in your HVAC system. When there’s not enough subcooling, the refrigerant pressure in the system can become elevated, which can lead to poor cooling performance and potential damage to your system. Low discharge pressure. Low discharge pressure is another sign of low ...In this HVAC Video, I Show SEVERELY UNDERCHARGED, UNDERCHARGED, CORRECTLY CHARGED, and OVERCHARGED Scenarios on a Running R-410A Refrigerant Air Conditioner ...

Superheat is calculated as the difference between the saturation temperature of a substance and the actual temperature of the gas. 3 When it comes to HVAC, refrigerants often boil at much lower temperatures than water. For example, if a liquid refrigerant boils at -10 degrees and is then heated up to -5 degrees, it has been superheated by 5 ...20°F. Notice the 30°F of liquid subcooling backed up in the condenser in this overcharged system. Because of this overcharge, the condenser will have too much liquid backed up in its bottom, causing high condenser subcooling. With an overcharge, increased liquid subcooling amounts will be realized in the condenser.Bryan teaches a class about what superheat signifies. Superheat is the difference between a vapor's actual temperature and its suction saturation temperature; it lets us know how much an HVAC system feeds its evaporator coil with boiling refrigerant. Liquid refrigerant goes into the metering device, and there needs to be enough liquid going ...Subcool low and Superheat high I had a new goodman heat pump 410a 15 seer and air handler unit installed last week. The installer had overcharged it the first time and had to return to cool the compressor and remove coolant. I dont feel it is working as it should after research on the proper method to ensure the superheat and subcool are within ...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 …High superheat and high subcool is usually a indicates an restriction in the refrigeration line. Reply . 06-04-2014, 11:19 PM #5. hvacrmedic. View Profile ... Your pressures seem to be a bit low for 410. Try charging to 130(L) and 325-330(H). Reply . 06-05-2014, 11:51 AM #12. gravity. View Profile View Forum Posts

Nslij follow my health.

Figure 1 is an example of a superheat-charging curve instead of a table. The curve is based on 400-cfm/ton airflow at 50% relative humidity across the evaporator coil. The steps to charge a system according to this curve are listed below. 1. Measure indoor drybulb temperature (DBT).Low subcooling for R22. Low subcooling usually means your system is undercharged or has a dirty evaporator coil. It's like running your car with low tire pressure - it won't perform well. The solution? Add refrigerant or clean the coil, depending on the issue. High subcooling for R22. High subcooling often indicates overcharging or a ...An undercharged system will exhibit low operating pressures, low condenser subcooling, high evaporator superheat, reduced compressor motor winding cooling, reduced cooling, and low temperature differential across the evaporator coil, said Eugene Silberstein, director of technical education and standards, The ESCO Institute, Mount Prospect ...Subcooling high, superheat low, vsat low, suction line low and liquid line normal/high, Brand new install, ArcoAire - Answered by a verified HVAC Technician. We use cookies to give you the best possible experience on our website.

Figure 1 is an example of a superheat-charging curve instead of a table. The curve is based on 400-cfm/ton airflow at 50% relative humidity across the evaporator coil. The steps to charge a system according to this curve are listed below. 1. Measure indoor drybulb temperature (DBT).A high superheat is an indication of either a low refrigerant charge or a liquid line restriction problem. To tell the difference between the two problems, we look at subcooling. A system with a low refrigerant charge will have a low subcooling. A system with a liquid line restriction will have a normal to high subcooling.Oct 12, 2018 ... When the suction pressure is low, the technician should take the subcooling and superheat inside and outside. ... If the superheat is high, you ...Step-by-Step Low Superheat High Subcooling Fixes. Once you’ve identified low superheat high subcooling imbalances in your refrigeration system using the diagnostic tools and equipment mentioned earlier, it’s time to take corrective action. Here’s a step-by-step process to help you address these issues effectively: 1. Ensure Safety …proper low- and high-side pressures, set superheat and subcooling temperatures, and to set pressure controls. The tempera-ture glide of a blend will determine how the PT chart will look. Therefore, a quick review of tem-perature glide from last month's arti-cle is necessary: • As a portion of a refrigerant blend works its way down the lengthCheck your wetbulb return air temperature - can use it to determine target supply temperature. 15F drop may be okay if it's relatively humid or the blower speed is set high. On a 3 ton drive furnace the fan should be on high or medium high for 2.5 tons, depends on your air ducts. On a 4 ton drive - lower.Jul 19, 2016 · Low airflow typically not related to high superheat. High superheat and high subcooling often indicate a restricted metering device, since the evaporator would be starved and liquid refrigerant wouod be stacking up in the condenser. And if that was the case I don't think the unit would cool or dehumidify the house very well. Evaporator Superheat Method: 1. Take the suction line pressure and temperature at the condenser's suction service valve (air conditioning) or service port at the compressor (heat pump). If you use a probe-type thermometer, put a piece of pipe insulation around the probe and pipe. 2. Jul 24, 2018 · From the Goodman manual for that model. Outside drybulb 95F inside drybulb 80F. Hi pressure = 335 Psig, Lo pressure 130 Psig. Which is 20-30 psi off on both. But I was under the assumption if it where low on 410a there would be high superheat and high subcooling. Like I said I’m new. With the excessive subcooling and no superheat, I am confused. 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.

Nov 21, 2023 · Superheat and subcooling data can help you pinpoint these issues quickly. Common Causes of Superheat and Subcooling Imbalance. Common reasons for superheating and subcooling include issues such as liquid line restriction, malfunctioning metering systems, and limited airflow, all of which can lead to high superheating and low subcooling levels. 1.

Has been checked numerous times. 1 thing that stands out is..the superheat is always normal but subcooling is always real low, usually 2 or 3 degree subcooling. ... Some units operate with a very low subcooling, such as window units & some self contained units. Also saw where, some new high efficiency equipment runs as low as 4-F subcooling.High superheat - refrigerant is boiling off faster in the evaporator, meaning the evaporator is starved. This leads to higher suction (vapor) temperature that can lead to overheating the compressor although that's rare. Typically caused by high heat load or undercharge. Low superheat - refrigerant is boiling slower in the evaporator, meaning ...A) A high subcooling and a high superheat. B) A low subcooling and a low superheat. C) A high subcooling and a low superheat. D) A low subcooling and a high superheat. Question 2 A problem that can look like low refrigerant charge if a service technician is only looking at system pressures is: A) Low evaporator airflow. B) Low condenser airflow.Jul 8, 2022 · High superheat low subcooling is when there is a limited flow of refrigerant in the evaporator and a limited flow of the refrigerant in the condenser. It is worth noting that in systems with liquid line receivers, subcooling will not increase because the liquid will go to the receiver instead of the condenser although the receive line filter is ... ค่ามาตรฐาน Superheat กับ Sub-cooling ของสารทำความเย็น R22 มีค่าเท่าไหร่ครับ ... - อุณหภูมิของท่อน้ำยา ด้าน Low และด้าน High - แรงดันของน้ำยา ด้าน Low ...Superheat determines by how many degrees of temperature refrigerant vapor increases in the system. We are usually looking for 7°F to 15°F superheat.Too low superheat (below 2°F) = Risk of flooding the compressor, too high superheat (above 15°F) = Risk of overheating the compressor.More about that in our general superheat and subcooling …4 Using Table 2, select the column which is closest to the measured vapor pressure. 5 Scroll down the column to find your calculated superheat. 6 Read the required vapor line temperature at the intersection. (°F) If the measured vapor line temperature does not agree with the required vapor line. 7 temperature, add refrigerant to lower ...Here is a table with these causes that will help us understand why we get low superheat normal subcooling: Low Superheat Causes: Non-Normal Subcooling Causes (High Or Low): Indoor airflow (CFMs) is too low. Oversized AC unit. Outdoor airflow is too low (or condenser coils heat exchange is impeded). High refrigerant charge (overcharged AC unit).Step-by-Step Low Superheat High Subcooling Fixes. Once you’ve identified low superheat high subcooling imbalances in your refrigeration system using the diagnostic tools and equipment mentioned earlier, it’s time to take corrective action. Here’s a step-by-step process to help you address these issues effectively: 1. Ensure Safety Precautions

Motorcycle wreck in amarillo last night.

Joannes san diego.

Many servicemen experience service calls where the compressor has both a low head pressure and a high suction pressure. There are three main reasons why a reciprocating compressor will simultaneously have a low head pressure and a high suction pressure. ... Condenser subcooling: 10 Evaporator superheat: 15 Compressor superheat: 45 Here are some ...Compare credit cards with no annual fee and low interest to find the best deal. Apply online for the best credit card with low interest and no annual fee. WalletHub makes it easy t...High superheat can be caused by (the culprits that at the same time cause low or high subcooling are crossed out): Low refrigerant charge. Restriction in the liquid line. Too …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.To check subcooling, attach a thermometer to the liquid line near the condenser. Take the head pressure and convert it to temperature on a temperature/pressure chart. Subtract the two numbers to get the subcooling. For example, 275 psi head pressure on an R-22 system converts to 124°F. The liquid line temperature is 88°F.For superheat measurement, we use the blue low side gauge. The red one (high side) is for measuring subcooling on the liquid line. Needless to say, we: Don’t want a very low superheat (0°F, 1°, or 2°F) since this indicates liquid refrigerant might be entering the compressor. The compressor can only handle vapor, not liquid.162. 25. I know that having both high superheat and low subcooling on an Air-Conditioner (A/C) is a strong indication that an air-conditioner does not have enough refrigerant. When the charge on an A/C is low, there is less refrigerant that enters the evaporator. When there is a lower amount of refrigerant entering the evaporator, it takes …System Information R22 2.5 ton: Low Side: 115. High Side: 240. Return Air: 83. Suction Line Temp: 75. Measured Super heat: 5. Super heat should be around 15. Low superheat is an indication that liquid refrigerant not changing state in the evaporator and is possibly flooding back to the compressor.High evaporator superheat; High compressor superheat; Low condenser subcooling; Low compressor amps; and; Low condensing temperatures and pressures. Also, remember that it is the British thermal units (Btu) that determine how much heat content is being absorbed by the evaporator, not its temperature. Temperature is simply a measure of the heat ...Resources & Apps. JB Industries SH-35N Superheat Subcooling Gauge Digital with Memory has the capability of saving low, high, and average values that can be analyzed later and has preloaded values for pressure and temperature of R-22, 31, and other popular refrigerants. JB Industries SH-35N includes an A34000 access tee, 6 foot dry/wet bulb ...The higher the efficiency of a system, the more critical it is that it is charged properly. The Fieldpiece Superheat and Subcooling for Air Conditioning and Refrigeration meter, model SSX34, measures suction line, or low side, line temperature and pressure. It then calculates actual superheat in real time using built in P/T charts. ….

Superheat is measured as the difference between the actual temperature of refrigerant vapor at a certain point and the saturation temperature of the refrigerant. It’s not complicated, but for a beginning tech, it might be.”. Superheat may be so complicated just because of the term “heat,” Tomczyk said. “Because something can be minus ...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 …High Suction - Low Superheat and No Subcooling 2.5 ton lennox condenser 3 ton drive on blower 3.5 ton evap 50 evap 45 SLT 100 condensing temp 105 LLT ... Elevated suction, low superheat, lowish head and low subcooling are typically symptoms of an overfeeding metering device. But 10 SC and 7 SH are reasonable …Robo 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.on target subcool with high superheat could mean a few things. 1. charge is low and condenser is underperforming 2. evap/condenser performing normally, but low charge takes txv out of range 3. low charge with restricted metering device. Reply . 06-07-2020, 11:28 PM #18. Adlerberts-Protege.In Vegas, all the indoor relative humidity is very low, abt 30 percent, so after measure the webbulb and outside condenser ambient temperature, the superheat is way below zero, so I decide put it at 5 degree. Even that, I couldnt reach it. The more R22 I added, the little increase in low pressure but high jump in head pressure. The latest like thisAs 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 ...low Suction press / low suct line temp indicates low air flow through evap. coil. But, 245# head on 78 degree day seems a little high, especially with only 60# suct. Of course 78 'f' outside is going to make yur condenser very efficient, so the increased subcooling could be attributable to the OAT. Low subcool high superheat, Well, 304-psig is 96-F SCT, therefore the suction line would have to be 89-F to get 7-F subcooling. A 156-psig is 55-F SST, a 56-F suction line would be around 1-F superheat. Many heat pumps use 10 to even 7-F TXV superheat. Appears beenthere nailed it, you appear to be using the pressure saturation temps., Superheat that is too low or too high may cause damage to a compressor. A refrigerant with a 0°F superheat value (saturated refrigerant) at this location indicates that some amount of liquid refrigerant is returning to the compressor. In this condition, the amount of liquid refrigerant returning is unknown, but any amount is too much. ..., What is the reason a dirty evap would cause higher than normal subcooling? I understand low superheat low suction pressure which would lower high side pressure. Would the lower high side pressure cause refrigerant to condense at a lower temp thereby increasing liquid level in coil thereby increasing subcooling? Any help much appreciated. I am thinking less refrig vapor (less dense) so less ..., Anything above the boiling point is all vapor, and it's superheated. Very high superheat indicates that the refrigerant boiled off very early in the evaporator, meaning that the system could be low on charge. On fixed-orifice systems, you charge a system via superheat. Zero superheat indicates that you have liquid in the suction line., How to check, measure, and read superheat and subcooling on a central air conditioner unit. In this video I do not go into the details of superheat and subco..., Lowe’s is the second-largest hardware chain store in the country, and one of America’s largest retailers, reports the website The Balance. As of 2018, it had just under 2,400 locat..., High subcooling is usually accompanied by high head pressure because liquid is displacing available condensing area. Low superheat, low evaporator load - dirty filter, slipping belt, low fan speed, filthy coil. High superheat, evaporators being starved for refrigerant if suction pressure is low. If suction pressure is high and superheat seems ..., The difference of the two temperatures is the subcooling value. TROUBLE DIAGNOSIS. Data from superheat and subcooling measurements can be useful for determining various conditions within the HVACR system, including the amount of refrigerant charge and verifying the operating condition of the metering device., Calculating superheat can tell us how far liquid Freon is traveling through an evaporator coil. If superheat is too high, there’s less liquid and more gas in the coil. This can cause overheating. If superheat is too low, more liquid and less gas are in the coil. This can cause flooding and damage in the compressor., Evaporator Superheat Method: 1. Take the suction line pressure and temperature at the condenser's suction service valve (air conditioning) or service port at the compressor (heat pump). If you use a probe-type thermometer, put a piece of pipe insulation around the probe and pipe. 2., And yes, you can have too much subcool, but don't want to since it will, as been talked about before "destroy" the capacity of your system! and will lower the capacity of your condensor. Last edited by Lowrider; 03-03-2007 at 10:05 PM . 04-03-2007, 06:23 AM #15. Gary., When the device overfeeds, there are high chances for both the suction pressure and the discharge pressure to increase. 3. Reduced airflow through the evaporator. One of the most common reasons for low superheat is due to reduced airflow. With reduced airflow, there isn’t enough warm air to vaporize the refrigerant., I agree, charge with suction superheat on straight cool [only] and then verify the subcooling with a clean-as-new condenser coil. The subcooling changes as the coil ages too. Verify with checking Discharge superheat [apx 100 degrees]. Charging with subcooling only works to get the highest efficiency on High SEER matched system., This will cause the compressor superheat to be high. The 100 percent saturated vapor point in the evaporator will climb up the evaporator coil, causing high superheats. Low Amp Draw High compressor superheats and low suction pressures cause low-density vapors to enter the compressor., High superheat and high subcool is usually a indicates an restriction in the refrigeration line. I'm new here, just wanted to grab some knowledge. I'm working with a newer Lennox R410A (13SEER) unit. The call was for not cooling properly. Any help would be great! Your subcooling is 19° and your superheat is 16°., In my thread asking how high charge level causes high subcooling, you told me that low charge level causes low superheat because the refrigerant gets subcooled less in the condenser which makes the refrigerant enter the evaporator at a warmer temperature, which leads to more superheat. ... High superheat with low condenser sub-cooling generally ..., When the device overfeeds, there are high chances for both the suction pressure and the discharge pressure to increase. 3. Reduced airflow through the evaporator. One of the most common reasons for low superheat is due to reduced airflow. With reduced airflow, there isn't enough warm air to vaporize the refrigerant., The TXV also needs a proper pressure drop (about 100 PSI); without that pressure drop, the TXV can't do its job properly. When the suction pressure is low, the technician should take the subcooling and superheat inside and outside. The goal is to look for the temperature differences between the inside and outside measurements., Oct 29, 2022 · The 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 ... , To use our two examples from the previous paragraph, R134a at 0 psig and -5 F has 10 degrees of superheat, and the same refrigerant at the same pressure but at -20 F has 5 degrees of subcooling. These concepts of saturation, superheat, and subcooling are the foundation of all sealed system troubleshooting., If the metering device is a fixed orifice such as a piston or capillary tube, the refrigerant charge of the system can be checked with Total Superheat. If the metering device is a TXV then the refrigerant charge can be checked with Subcooling. See the Picture below. If the unit has a TXV, check for the Target Subcooling posted at the outdoor unit., A low suction superheat does not 'indicate' an overcharge. Low suction superheat is the result of too much refrigerant in the evaporator for the heating loading of the evaporator at that moment in time. Post the startup report data: Outdoor Ambient temperature. Condenser air temp in. Condenser air temp out., Low superheat high subcooling is a common issue with AC units. There are 5-6 low superheat causes and 3 high subcooling causes. By comparing these causes, we can see which ones are the reason we have low superheat and high subcooling. Here is a chart of low superheat causes (on the left) and high subcooling causes (on the right). The …, What would cause an AC unit to have low superheat and low Subcooling? It was an 80F day and my low pressure was 90 and my head pressure was 263. Now I did added refrigerant but that just made my low pressure go lower and my superheat to go lower. My suction temp was 32 and my evap was 30. System is a 2 ton with a txv and air flow is adjusted for a 2 ton my static pressure is 0.49 across the ..., Unfortunately, there is a lot of misunderstanding as to what exactly Superheat and Subcool actually are and even less understanding on how to measure it. There are so many novice technicians that get 'stumped' on a system without even checking Subcool or Superheat temperatures…. or if they did check them they checked in the wrong section., I'm a new tech and I am confused about subcool and liquid line restrictions. I've read that a unit that is low on charge will have low subcool and high superheat. Units that have LL restrictions but a good charge will have good subcool, around 10 degrees, and high superheat., SUPERHEAT & SUBCOOLING High Superheat & High Sub-cooling: -- restriction/blockage in coil, orifice or line set -- too little refrigerant in low side (suction line) ... Low Superheat & High Sub-cooling: -- Overcharged on both sides (suction line & liquid line) -- remove, adjust charge TROUBLESHOOTING: SUPERHEAT, SUBCOOLING, DELTA T 1. LOW CHARGE, One sign of low subcooling is high suction pressure in your HVAC system. When there's not enough subcooling, the refrigerant pressure in the system can become elevated, which can lead to poor cooling performance and potential damage to your system. Low discharge pressure. Low discharge pressure is another sign of low subcooling., If superheat is high and sub-cooling is low: Charge must be adjusted. System undercharged. If superheat is low and sub-cooling is high: Charge must be adjusted. System overcharged If superheat is high and sub-cooling is high: Could have blockage in coil, orifice or line set., What causes low superheat and high subcooling? Because these readings are normal, the low suction pressure is caused by insufficient heat getting to the evaporator rather than low refrigerant. CAUSE #2: A faulty, plugged-in, or undersized metering device is to blame. As refrigerant is added to TXV systems with high superheat, double-check the ... , High Subcool, Low Charge First pic was initial reading, liquid pressure got around 450 soon afterward, and subcool went up to 30+. I ended up adding a little over 1lb to get it to 10 subcool. ... 1deg subcool, superheat went up and it all of a sudden looked low. So I charged it then it was great. Reply reply, Superheat is a temperature value measured of vapour (steam or refrigerant) above boiling point. The reading will show the amount of refrigerant going through the evaporator and whether it is sufficient. …, 28. Post Likes. high super heat low suction. any ideas. I am working on a ruud heat pump. Freeze up problems. Low suction pressure, 24 superheat, 8 subcooling. 14 degree air drop across my coil. I have evacuated and wieghed in a charge r-22 and replaced txv. No kinks in line set and not a plugged filter dryer. .5 static pressure across …