This brief guide explains how to measure superheat and subcooling. As a review, superheat is heat added to the refrigerant above its boiling point/saturation. Subcooling is removing heat from refrigerant below saturation. Measuring the superheating and subcooling of the refrigerant tells you if it is under the proper amount of pressure and can lead to a diagnosis of the refrigerant level and mechanical issues.

Step-by-step instructions on how to calculate superheating and subcooling values plus possible diagnosis using the measurements are included. Furthermore, the tools, tips, and techniques below assist you in streamlining the process for faster maintenance and diagnosis of the problem.

Why You Might Need to Know How to Measure Superheat and Subcooling

Knowing how to calculate superheat and subcooling (aka sub-cooling and subcooling) values is essential to ensuring proper refrigerant charge in air conditioning systems and refrigeration units. The measurements also assist in troubleshooting problems with the equipment. This is important because knowing superheat, subcooling and temperature difference (Delta) across a coil:

• Allows an HVACR technician to ensure refrigerant levels are properly maintained for maximum efficiency and performance
• Safeguards against improper diagnosis and repair such as diagnosing and replacing the compressor when the problem is something else. That’s a costly but very common mistake.

Tools and Specs to Keep in Mind

The primary tool for the job is a superheat/subcool meter or gauge. They’re produced by many brands in a price range from about $70 to $250. We suggest looking for one with presets for the refrigerants you work with most commonly – R22, R410a (Puron), R134a and R404a, for example. That eliminates the need for inputting the specific refrigerant’s specs.

A handy assistant when converting low-side and high-side pressure to temperatures is a phone app like Emerson’s Check & Charge. The free app is one of many great HVAC troubleshooting apps every tech should have. Its features include superheat (non-TXV) and subcooling (TXV) calculators for R22 and R410A. Check & Charge is available here for iOS and here for Android. A companion to it is the Danfoss Refrigerant Slider with pressure-to-temperature conversions for 80 refrigerants. Those are specs you must know to successfully evaluate the performance of the equipment you’re evaluating.

How to Measure Superheat and Subcooling

Here’s how to determine these values in a few easy steps for each.

Calculating superheat:

1. Measure the low-side pressure with your gauge.
2. Convert pressure to temperature with an app, slide or chart.
3. Next, take the temperature of the suction line where it leaves the condensing unit, though stay 4-6 inches from the compressor.
4. Use your measurements to determine the amount of superheat. For example, if suction line temperature is 65 degrees and your conversion of the suction pressure to temperatures yields 50 degrees, then the difference is 15 degrees of superheat.

Calculating subcooling:

1. Measure the high-side pressure with your gauge.
2. Convert pressure to liquid temperature with an app, slide or chart.
3. Measure the temperature of the liquid line where it meets the evaporator and before the metering device.
4. Finally, determine the difference in the temperatures determined in Steps 1 and 2 by subtracting the liquid temperature from the saturation temperature of the refrigerant you’re working with. A difference of 12-15 degrees is standard. For example, if your conversion of pressure to temperature yields 115 degrees for saturation and the liquid line temperature is 100 degrees, that’s 15 degrees of subcooling.

Note: Superheat should be 12-5 degrees in ambient air temperature below 85 and 8-12 degrees in warmer air. Subcooling should be 5-18 degrees, at the high end of that spectrum when the equipment has a TXV. Always go by the manufacturer’s specifications.

Using superheat and subcooling data in troubleshooting:

• Low superheat: Too much refrigerant in the evaporator. It’s likely overcharged.
• High superheat: Too little refrigerant in the evaporator. This might indicate that the system is low on refrigerant, but it’s just as commonly caused by insufficient heat getting to the evaporator (dirty filter or blower, undersized or blocked ductwork, plugged evaporator coil) or a dirty/defective metering device.

Caution Notes

Don’t try this at home! Diagnosing and repairing air conditioning and refrigeration is one of those jobs experienced DIY homeowners are wise enough to steer clear of. Moreover, working with refrigerant is not a DIY job unless you’re a licensed HVACR technician.

Only licensed techs can legally handle refrigerants. Additionally, overcharging and undercharging a system lead to serious issues with air conditioning and refrigeration equipment. There’s no reason to turn what might be a small problem into a major mechanical failure.

And here’s an important caution: Refrigerant might not be the issue. If you misdiagnose the cause of the problem, your solution won’t work. Consequently, the right approach is to leave the work to an experienced HVAC technician.

Hiring a Pro for your AC or Refrigerant Job

Finally, if this post interested you, it’s possible you ARE an HVACR pro. If so, we hope it was a good refresher in superheat and subcooling basics. We’d enjoy getting your feedback in the Reply box below. If you’re a homeowner diagnosing an AC or refrigerant issue, we’d recommend discussing the issue with a professional.As such, look for one certified by N.A.T.E., the North American Technician Excellence. The organization provides the most broadly respected training, testing, and certification for professionals in the HVACR industry. If you’re a hands-on homeowner that likes to know what the issue is, so you can fix it yourself or knowledgeably discuss it with a pro, you probably know other homeowners who feel the same. In the end, perhaps they’d benefit from this information on superheating and subcooling, so feel free to share!

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Our Amana AC guide is your one-stop place to research for the right Amana central air conditioner. Then, you can decide if the brand is a good choice for your residential or commercial space. The information below allows you to browse Amana air conditioner performance with technical specification and top units in each class.

Amana AC pros and cons offer insight for comparing this brand with others we’ve reviewed. Our reviews include Goodman, Bryant, and Carrier.

Amana Air Conditioner Brand Overview

George Foerstner designed and started manufacturing a beverage cooler in Amana, IA, in 1934. His company grew into the Amana Corporation and enjoyed decades of innovative productivity. Some examples are the first upright freezer and first side-by-side refrigerator. In 1997, Goodman Manufacturing acquired Amana. The company maintained it as a separate brand but with a nearly identical product lineup to Goodman’s.

The next chapter began in 2014 when global HVAC giant Daikin acquired both brands. Currently, the Amana air conditioner lineup is being upgraded to make Amana/Daikin one of the top five to ten brands in the industry. This places them alongside Trane/American Standard, Carrier/Bryant, Maytag/Westinghouse and Lennox. Goodman remains the leading budget brand of HVAC equipment.

Amana Air Conditioner Technical Specifications

The eight Amana air conditioner models perform well in three classes:

• Base Amana ACs: These single-stage air conditioners with SEER ratings for efficiency between 14 SEER and the top pick in this series, the 16 SEER Energy Star-qualified Amana ASX16 central AC;
• Better Amana air conditioners: The ASXC16 with 16 SEER efficiency and the ASXC18 with 19 SEER efficiency, contain a two-stage scroll compressor for low-capacity/high-capacity cooling. This tool is quieter, reduces humidity better than single-stage models and improves temperature balance;
• The Amana AVXC20 is the best Amana air conditioner currently available. It has an outstanding 24.5 SEER rating made possible with the inverter technology compressor. The compressor runs at variable speed like cruise control with slight modulations. It aims to deliver precise cooling and premium dehumidification;
• Both Amana two-stage models and the variable speed AVXC20 are wired for an Amana ComfortNet Communications thermostat. This is a $500 upgrade that synchronizes system components to ensure the best possible performance and efficiency;
• As with all brands, superior efficiency and climate control go hand in hand. This is because the longer, slower cycles of two-stage and variable-capacity compressors make the best use of energy too.

Pros and Cons of Amana Air Conditioners

With the acquisition by Daikin, Amana is once again an industry leader. Here are reasons to consider Amana and a few potential disadvantages too.

Amana AC Pros

• The range of models in price, performance and efficiency create options for homeowners in all climates;
• Try replacing an old AC with a 19 SEER Amana ASXC18 or the 24.5 SEER Amana AVXC20. Then, you’ll get eco-friendly cooling that will cut energy costs up to 60%;
• The 24.5 SEER efficiency of the AVXC20 is in the top three of all models with the Lennox XC25 (26 SEER) and Maytag PSA4BI (25.5 SEER);
• Amana air conditioner models that qualify for Energy Star might also be eligible for energy rebates. So check with your local unity company or look for local rebates;
• Amana warranties are among the very best in the industry. They include a complete unit replacement warranty, covering the compressor on the top models;
• Even the base models ANX13 and ASX13 have 10-year warranties. All this time, base models from top brands like Carrier come with 5-year warranties and a higher price. That makes Amana a very good value;
• Amana air conditioners consistently receive verified user ratings above 90%, often as high as 98% recommendations.

Amana AC Cons

• The upgrade to Amana products has happened in the last few years. So if you choose Amana, make sure the equipment you receive was made in 2016 or later. This way you also ensure you’re getting a superior AC or complete HVAC system;
• As of this writing, none of the Amana control/thermostats are Wi-Fi enabled for controlling your system remotely using your phone and an app. But there are Wi-Fi thermostats like the ecobee3 and the 3^rd generation Nest thermostat that support Amana systems;
• With the upgrade in the quality of the Amana air conditioner lineup, it is likely that prices might rise and costs will be higher. But Goodman’s lineup that Amana was once identical with should remain a best seller in the low-cost HVAC market niche;
• There might be some early confusion about Amana’s old and new units. This is because the newer models need Daikin replacement parts, not the old Amana parts. But the confusion should be cleared up within the first few years. Also, new ACs shouldn’t require much service anyway.

Things to Consider Before Buying an Amana Air Conditioner

• Efficiency: The hotter and more humid your climate is on this Climate Zone map and/or the longer you plan to stay in your current home, the more cost-effective it is to buy a very efficient Amana air conditioner. It can be the 19 SEER ASXC18 or the 24.5 SEER AVXC20. In cool climates where running the AC is an occasional need, a moderately efficient model like the ANX13 or ANX14 cost less compared with more efficient models.
• Eco-friendliness: If minimizing your environmental impact is important to you, then buy the most efficient AC model you can afford. Keep it maintained to run as efficiently and durably as possible.
• AC vs. heat pump: ACs come with gas or oil furnaces, most of the time. But did you know that a heat pump is a more efficient way to heat than even an efficient gas furnace? And heat pumps provide air conditioning too. If you’re buying the equipment for new construction or are replacing an entire HVAC system, talk to your HVAC contractor about heat pump or dual fuel heat pump options.
• AC size: If you’ve added insulation or upgraded windows with energy-efficient glass, your replacement AC probably doesn’t need to be as large as the old one. It also shouldn’t be so. Talk to your contractor about doing a Manual J load calculation to accurately size the unit.

Choosing and Cooling

The best way to get a quality Amana air conditioner properly installed is to request estimates from three of the top HVAC companies in your area. Look for an experienced installer that is licensed, insured and has a proven track record of quality installation and excellent customer service.

We make HVAC research easy, and we hope it’s been interesting too. If your friends and followers might be researching an AC or HVAC system for their homes, perhaps they’d benefit from you sharing this Amana AC guide with them!

When looking for a new central air conditioner, it’s important to know that the lowest central air conditioners prices are not necessarily the best prices. In fact, pricing should be among the last criteria on your list. Here’s what to focus on when buying a central air conditioning unit, and how each aspect influences the pricing of said unit:

Central Air Conditioner Prices: Why the Big Differences?

Central air conditioner units prices start off at about $800 for a new appliance and can go well beyond $10,000. This means installation and any additional work will increase the overall cost. Although the price range is extensive, it’s not unjustified. The most important variables when talking about central air conditioners prices are capacity, efficiency, and brand. Here’s a breakdown of the costs involved in acquiring and installing a new central air conditioner:

Central Air Conditioner Prices by Brand

Here are the most popular central air conditioner brands and their lowest, highest, and average prices:

Note: These prices only refer to the central air conditioner unit; Installation costs are not included in the examples above.

As you can see, the price range is considerable for many manufacturers. The lowest price usually refers to the small, less efficient, and usually, older models that are still available for sale. The highest prices are those of new appliances that feature the highest efficiency ratio and the most powerful compressors.

Even though the manufacturer is an important criterion when looking for a new central air conditioner, it is not the only one to matter. Capacity and efficiency are critical aspects that need to be taken into account when looking for a new central air conditioner.

Central Air Conditioner Prices by Capacity

Generally, the climate zone you live in determines the capacity of your future central air conditioner unit. However, the area of your home is a decisive factor, too. Here are the average prices for different central air conditioner units in terms of capacity:

Note: 1 ton = 12,000 BTU (British Thermal Units) = the amount of energy it would take to melt 1 ton of ice in 24 hours. To put things in perspective, a 12,000 BTU central air conditioner will be able to cool off about 500 square feet.

When buying a central air conditioner, it’s important to accurately match the unit’s capacity with the space it needs to cool off. An appliance that is too weak will obviously not be able to provide a comfortable temperature during summer months. However, one that’s too strong will cycle on and off every few minutes, thus becoming inefficient. In addition, given it will not work permanently, it will not be able to control the air humidity – an important factor when it comes to your comfort.

Central Air Conditioner Prices by Efficiency

The most efficient central air conditioners are usually the most expensive, but they are the cheapest to run. Therefore, the cheapest appliance is not always the best one for long-term use. in fact, efficiency should be among the first things to take into account when looking for a new central air conditioner. Here are the average prices for central AC units in terms of efficiency:

No matter their efficiency ratio, central air conditioners can be heavy consumers – especially if you live in warm or hot areas. At the moment of writing, the U.S. government offered a tax credit of about $300 for those who purchase central air conditioners that comply with Energy Star rules and have a SEER of 16 or more.

The highest efficiency central air conditioners are the best for our environment: They use significantly less energy and produce fewer greenhouse emissions. However, when it comes to our wallets, things are not that simple. There’s a fine balance between efficiency and overall costs, balance that mainly depends on the following factors:

• How much and often you will use your central air conditioner.
• How well insulated your home is.

For example, if you live in the northern part of the country and only use the central AC 2 or 3 months per year, sending more than $3,000 for a highly efficient appliance will not make as much sense as spending $2,000 for an average efficiency one. On the other hand, if you live in Southern California, a highly efficient central AC is the best way to go – but only if you have proper home insulation.

Extra Costs of a Central Air Conditioner Unit

The following initial expenses might save you more in the long run:

A Thermostat

A programmable thermostat is one of the easiest and most efficient ways to reduce energy consumption in your home. It can cost anywhere from $20 to $400, but will pay for itself in a month or so. A thermostat adjusts the activity of your central air conditioner based on a pattern inputted by you.

Extended Warranty

If you feel the manufacturer’s default warranty is not enough, you can invest in extending it. Default warranties usually last between 8 and 15 years, with an average of 10 – 12 years. Many sellers offer 1, 2, or 5 extra years of warranty for a few dozens or hundreds of dollars. This is particularly important for those who live in warmer climates since the appliance will be used more frequently.

Keep in mind the lifespan of a central air conditioner unit depends on how often you use it. The average lifespan of 10 years that most manufacturers promise refers to temperate areas where the appliance is used a few months per year. If you live is warmer climates with high humidity, or by the ocean where the air is saltier, your central AC is likely to last about 8 years or less.

Extra Functions

Most central air conditioners today come with a humidity control function. However, other features might be desirable for some customers. Quiet operation functions can be extremely useful for small homes or for those where the outside unit is placed near the bedrooms. Multistage compressors are another desirable feature in central ACs. They can significantly lower your energy bills and extend the appliance’s lifespan.

Central Air Conditioner Prices: Installation

Installation costs alone for a central air conditioning system range between $350 and $8,000 for a new appliance. Here’s the breakdown:

• Delivery costs: Completely depend on each retailer.
• Materials & supplies: Between $50 and $150 if your home already has ducts and they are properly insulated.
• Contractor(s): Between $300 and $2,000, depending on the amount of work needed to install the central AC unit. Some appliances can be installed in just a few hours with minimal effort, while others require extensive work. Under no circumstances should you install the central AC unit by yourself. This is a complex project that involves handling refrigerant, high-voltage electricity, and sensitive electronics – not to mention the environmental concerns that come with improper
• Ducting: Between $400 and $3,500, mainly depending on the size of your home.
• Insulation: Between $450 and $3000, depending on how many ducts you have in your home.
• Debris removal & cleanup: If you do not want to do this by yourself, be prepared to pay $100 at most for these services.

Some high-SEER central air conditioners will also require solar panels to keep the energy consumption to a minimum. Therefore, you might need to be ready to invest in these, too.

How to Find the Best Central Air Conditioner Prices

As mentioned before, the lowest price rarely is the best price. Here’s how to effectively find the best central air conditioner price and contractor:

• Ask yourself how long you plan on living in this house. If you are not sure, installing an expensive appliance might not be the best idea.
• Always check for references and read reviews for contractors.
• Ask recommendations and quotes from at least 3 professionals. Analyze what they have in common – ideally, they should have identical or similar capacities. Then, analyze their differences and see which ones matter the most to you. Maybe a certain model has an extensive warranty, while another is highly efficient. Use what you read in our article to decide which will fit your needs.
• Do not cheap out, but don’t go above your budget either.

Central Air Conditioner Prices Recap

All in all, installing a new central air conditioner will cost between $2,000 for small homes or apartments and $15,000 or more for large homes. Given the significant number of variables that decide the central air conditioner prices, it would be impossible to give a more accurate response.

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