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Bluon Accreditation Program

This program takes about 20 minutes, and by the end you’ll be a Tier I Accredited Contractor. Start here with this overview on R-22 replacement blends. Then you’ll answer a few review questions on the following page, and create a Bluon account to finish.


Bluon TdX 20 works great in both large and small systems, but there are certain critical things you need to know when converting systems to any refrigerant blend, including TdX 20! When you get Tier I Accredited, our warranty will cover TdX 20 when installed in systems up to 20 tons. When you get Tier II Accredited, our warranty will cover installations in systems over 20 tons. Simple!

Getting Tier II Accredited involves completing on-the-job installations with a Bluon Technician. If you are planning to install TdX 20 into larger systems but are not Tier II, you should at least contact us first! We can send our technicians out to assist on large jobs and ensure it’s done correctly. With our guys on-site, we can warranty the product, and credit that job toward a Bluon Tier II Accreditation!


Why you’ll be using R-22 replacement blends


The availability of refrigerants is impacted by an international treaty called the Montreal Protocol. The treaty is designed to protect the ozone layer by phasing out substances known to deplete it.

Under the treaty, early CFC refrigerants (like R-11) have been successfully phased out of use in most of the world. Newer HCFC refrigerants (like R-22) are on a phase out schedule that reduces how much R-22 can be imported each year.

No more R-22 will be imported into the US starting January 1 2020.

r22 decline graph

percentage hvac still use r22


The regulation is designed to slowly force HVAC-R users to replace their R-22 equipment with R-410A equipment. However, most users can’t afford to replace their equipment (which in many cases, still works just fine).

In fact, 60% of the world’s HVAC-R equipment is still R-22 equipment. In many cases, they still have 10+ years of useful life.


R-22 prices are rising dramatically. Soon R-22 will be difficult to obtain and cost prohibitive. As a result, R-22 replacements will become a major part of normal HVAC-R maintenance and repair jobs.


R22 replacement demand graph


Replacement refrigerants are different than R-22 in important ways.

All Replacements Are Blends
R-22 is composed of a single compound, whereas replacements are blends of two or more compounds.

Blends Have Multiple Boiling Points
The different compounds in blends mean that they have multiple boiling points. This is why PT charts for blends have two columns instead of one, because their boiling and condensing temps are different.

All Blends Have a Glide
The different boiling points of the blend constituents results in a Glide. Contrary to industry opinion, glides can be beneficial in a properly designed refrigerant.

All Blends contain HFCs
Because blends are HFC-based they must carry the mineral oil required by R-22 systems. This can happen in one of the following ways:

  • Change MO oil to POE
  • Use a hydrocarbon in the blend
  • Innovate a way for the HFCs to mix with MO

Different Pressures and Temperatures
Replacements operate at different pressures and temperatures than R-22.

Correct SH and SC are Critical
Proper Superheat and Subcool are very important.

Replacements Perform Worse than R-22
Virtually all replacements perform worse than R-22 on energy efficiency and capacity (except Bluon!)

r22 replacement differences

refrigerant blends contain hfcs

r22 replacements are blends


Replacements present new challenges for mechanical contractors

replacement blend problems

For contractors starting to work with blends, some of difficulties they face include:

  • Understanding the behavior of blends
  • Pre-existing problems can get worse
  • Accounting for pressure differences, controls, etc.
  • The impact of fractionation & volumetric issues
  • Tuning is mandatory
  • Client concerns: capacity and efficiency


Pre-existing conditions or problems in equipment can get worse when you convert the system to a replacement. Be aware of these common issues:

Airflow Issues
Equipment might have airflow issues.

Metering Device Problems
TXVs may not work. Non-Adjustable TXV’s may require conversion.

Crank Case Heater Failures
It is more critical that crank case heaters are properly functioning.

Oil Levels
Oil levels might be high or low.

Pressure Controls
Low Pressure and High Pressure controls may need to be calibrated.

Refrigerant Charge
Equipment might be undercharged or overcharged. As a general rule of thumb:

↑ Overcharged = Lower efficiency
↓ Undercharged = Lower capacity

hvac controls with blends

charge issues with replacement blends


r22 blend pressures

hvac replace metering txv devices

TXVs Need Adjustment
Replacing the refrigerant means adjusting TXVs.

EEV Software
EEVs need the proper software profile.

Fixed Metering Devices
Fixed metering device will require more or less refrigerant.

Hot Gas Bypass
Hot gas bypass valves will need to be adjusted or replaced.

Pressure Switches
Pressure switches may need adjustment.

PT Charts
Remember that PT charts have two sides. This is because the constituents in the blend have different boiling and condensing temperatures. Blend PT charts are not absolute, but represent a range between fully liquid and fully vapor. Constituents may be in different states somewhere between that range. This is called “Fractionation” (see below).


Multiple Temperatures
Blend vaporization/condensation happens at multiple temperatures as a result of fractionation.

Pipes Can Condense or Evaporate
Large or volumetric piping can produce unexpected condensing or evaporating issues.

Liquid leaks have smaller impact vs. vapor leaks. This is because in liquid form the constituents leak equally, but as vapor they leak unequally, which affects the blend ability to function.

Use the “20% Rule” with leaks: Generally if you’ve lost more than 20% on the vapor side, you should do a full recharge instead of just topping off.

fractionation glide hvac refrigerant

Fractionation: simply that blend constituents can be in a range of phases between liquid and vapor in the system.


20 percent rule recharge


Hvac digital guage

Glides and Pressures
Glides can actually be beneficial when tuned properly.

Subcool requires liquid line pressure and temperature from bubble column from PT chart.

Superheat requires suction pressure and temperature from vapor column from PT chart. The measurement locations matter.

Target Temperatures
Although pressures are different, target temperatures for the evaporator and condenser should stay consistent.

Example: If an R-22 system is operating with a 40 F evaporator coil and 105 F condenser coil, then the replacement should run at those same temperatures, as measured at the coil outlet. The pressures will be different. Remember that the refrigerant glide will account for the temperature change occurring in the coil.


Remember that you are now using TWO columns on the PT chart, not just one.

1. Condensing Temps
Use the Liquid (Bubble) column to determine Condensing (Bubble) temperatures.

2. Evaporating Temps
Use the Vapor (Dew) column to determine Evaporating (Dew) temperatures.

two column refrigerant pressure temp pt chart


r22 expensive

The price of R-22 is skyrocketing as its availability declines. The price will only continue to rise.

Energy Cost
Most replacements drive up the electricity use of the equipment, which means higher energy bills for customers.

Loss of Cooling Capacity
Most replacements reduce cooling capacity, making the equipment less effective.

4. Introducing Bluon TdX 20 (R-458A)

We set out to make an insanely great R-22 replacement blend. After five years of hardcore R&D, real-world testing, and approvals, we nailed it.

  • Energy efficient vs R-22 (saves up to 25%).

  • Virtually identical capacity to R-22 (+/- 3%).

  • No oil change required. Works with POE & MO.

  • Operates at lower pressures and temperatures.

  • Reduces vibration and boosts stability.

  • ASHRAE & EPA approved, warranty protected.


TdX 20 is the only replacement that actually upgrades your existing R-22 HVAC-R equipment.


HVAC-R systems work by changing a refrigerant between liquid and gas phases. TdX 20 takes this phase change to a whole new level.

  1. Five constituents phase change in a carefully orchestrated sequence.

  2. Heat is absorbed across more of the coil surface area, improving overall heat transfer.

  3. Compressor workload is reduced, resulting in less amp draw and lower compressor head temperature.

  4. Compressor stability is improved, resulting in less noise and vibration and more stable amp draw.

r22 vs tdx 20


Understanding how Bluon has your back

We know that R-22 replacement can be a headache. That’s why we provide industry-first tools and support to make the job easier.

  • Live tech support from expert techs
  • Mobile app with a database of thousands of HVAC units and individual replacement notes, plus guides and tools to make the job easier
  • Warranty protection

hvac bluon support for contractors


hvac tech help

Call Us for Help
If you run into problems or have questions on the job, we’re here for you. Just call live technician support hotline and talk to one our veteran techs. We have decades experience, and we’ve pretty much seen it all.

You can get call our support hotline through the Bluon mobile app.


We did the work so you don’t have to. Save time and do it right with our growing Best Practice guides for common procedures, including:

  • Recovery
  • Evacuation
  • Hot Gas Bypass Valves
  • Charging & Tuning
  • Crankcase Heaters
  • Leak Detection
  • 3D Scrolls & Off-Cycle Migration
  • Thermostatic Expansion Valves
  • Elastomer Seals & Gaskets
  • Pressure Set Points

HVAC best practices and how to

Best Practices are available to Accredited Contractors on our website and in our mobile app.


hvac system testing and sharing

Bluon technicians are actively installing TdX 20 in hundreds of systems. This helps us to:

Determine best practices, dos and don’ts
Outline solutions for challenging systems
Save you the frustration and learning curve

Our techs are in the field each week acting as your person recon group for difficult jobs.


An indispensable tool for HVAC techs

Equipment Database

Use the Bluon app to help you when converting R-22 systems to TdX 20.

Lookup 16,000+ HVAC Units
Sort by manufacturer and search the list of model numbers.

Get System Details
Know what you’re working with. Find tonnage, circuit info, refrigerant charge, compressor types and models, metering devices, fan and CFM info, electrical details, SEER & EER values, and more.

Original Manuals
Find full system manuals in the app.

bluon hvac app database

Individual Replacement Instructions

hvac app controls

When using replacement blends, you need to know what controls are present in the system, and how they should be properly checked and tuned. The Bluon app has you covered.

All units in the database are color coded based on what may be involved in the conversion process.

Green: Standard Conversion – Normal replacement job
Yellow: Possible Modifications – Some system modification may be necessary
Red: Do Not Convert – Not an R-22 system, etc.

Tapping on the conversion guidelines button shows the system controls (both standard and optional) and tells you how best to deal with each. Pump down circuitry, hot gas bypass, thermostatic expansion valves… you’ll find it here.

Replacement Toolbox

The app toolbox is a collection of helpful tools to help you with TdX 20 installation, tuning, and troubleshooting. Existing tools include:

  • Subcool Calculator
  • Superheat Calculator
  • PT Chart
  • Nitrogen Pressure Test Tool
  • Airflow Calculator
  • Pressure Set Point Tool
  • System Diagnostic Wizard
  • Airflow Diagnostic Tool
  • Subcool Calculator (R-22)
  • Superheat Calculator (R-22)
  • PT Chart (R-22)

hvac app tools iphone android

hvac app guides instructions

Guides & How-To

Use the app to brush up on the TdX 20 installation process with its extensive documentation and videos.

The complete Best Practices for dealing with common issues and procedures are here also.

Technician Support Hotline

If you have questions about a job or need help, PLEASE call us! Our technician support guys all have at least a decade or more of field experience, and are real-world experts with R-22 conversion and TdX 20.

You can call our Technician Support line directly from the Support tab in the app, 24/7.

hvac app tech support hotline


Installation overview

Bluon Conversion Recap

  1. Check filters and replace as needed.
  2. Check coils, clean as needed.
    • Visually inspect for signs of leaks (oil spots, bubbles, etc.) – the best time to identify a leak is before you take the refrigerant out.
  3. Verify proper airflow.
    • (generally 400 CFM / ton).
  4. Check general condition of unit looking for any abnormal wear and tear that might affect system performance (corroded contractors, clogged drain pains, etc.)
    • Replacing the refrigerant in a system with issues will make the existing problem worse.
  5. Record refrigerant type and original charge (usually found on data plate).
    • TdX 20 is compatible with R-22 and R-22 replacement equipment.
  6. Check metering device type.
    • If fixed, make note of type and style (piston, capillary tubes, etc.)
    • If adjustable, verify thermostatic expansion device (TXV) responds to adjustments. In 95% percent of cases, you’ll need to close the TXV by 1-4 turns.
    • If TXV is non-adjustable, you may need to replace or convert to adjustable (conversion kits available).
  7. Baseline system performance under full load and record for future reference.
    • Suction pressure/temperature, Liquid line pressure/temperature.
    • Return Air (RA), Supply Air (SA), Outside Air (OA) if air cooled, Compressor amperage.
    • Calculate Superheat and Subcool (use the Bluon Mobile App).
  1. Check for any pressure controls that may interfere with TdX 20 performance.
  2. Recover refrigerant using standard trade practices (generally down to 10” Hg).
    • Record amount of refrigerant recovered as this will be used later.
  3. Replace filter driers with HFC compatible driers within OEM recommendations.
  4. Check seals, pressure test with nitrogen, check for leaks (bubbles, standing pressure test, etc.)
  5. Evacuate system to 500 microns using standard trade practices.
    • Ensure system holds vacuum without rising above 1000 microns in 15 minutes.
  6. Charge system through liquid line to 80% of nameplate or charge recovered (whichever is less).
    • Meter in liquid TdX 20 to the suction line until suction pressure is at least 30 psig.
  7. Startup unit in accordance with OEM procedures.
  8. Once stabilized, dial system in according to metering device type:
    • Fixed: charge to Superheat (8-12 F at the evaporator outlet / 8-20 F at compressor inlet*)
    • Adjustable: charge to Subcool (8-12 F at the liquid line*), adjust to superheat.
      *Always refer to OEM recommendations first.
  9. Label equipment with provided TdX 20 tags (attached to cylinder stem).

Got it? Awesome.

Let’s move on to Step 2 and answer some review questions.