20 Best R12 To R134a [2024]

Are you looking for the best r12 to r134a? Based on expert reviews, we ranked them. We've listed our top-ranked picks, including the top-selling r12 to r134a.

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1 InterDynamics Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter Kit... InterDynamics Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter...
2 R12 to R134a Conversion Fitting Adapter Kit - R12 to R134a Retrofit Kit with High/Low Side Fitting,... R12 to R134a Conversion Fitting Adapter Kit - R12 to R134a Retrofit Kit with High/Low Side...
3 R12 to R134A AC Retrofit Fitting Adapter Kit, R12 R22 to R134A High/Low Fitting Port Retrofit... R12 to R134A AC Retrofit Fitting Adapter Kit, R12 R22 to R134A High/Low Fitting Port Retrofit...
4 R12 to R134A Conversion Quick Connect Coupler Kit, High/Low Side 90 Degree Angle Quick Coupler... R12 to R134A Conversion Quick Connect Coupler Kit, High/Low Side 90 Degree Angle Quick Coupler...
5 Micro Traders R-12 to R-134a High Low Side Retrofit Conversion Adapter 1/4 SEA Valves Caps Fitting... Micro Traders R-12 to R-134a High Low Side Retrofit Conversion Adapter 1/4 SEA Valves Caps...
6 Bullet Piercing Valve Kit with Dust Cap Converts R12 to R134A Fit 7/16 Inch Low Side Port BPV-31... Bullet Piercing Valve Kit with Dust Cap Converts R12 to R134A Fit 7/16 Inch Low Side Port BPV-31...
7 R12 to R134 A High/Low AC Fitting Port Retrofit Conversion Adapter, Quick Coupler Valve A/C 90°... R12 to R134 A High/Low AC Fitting Port Retrofit Conversion Adapter, Quick Coupler Valve A/C 90°...
8 Aupoko R12 R22 to R134A Conversion Adapter Kit, R12 to R134A Retrofit Valve Fitting Kit for A/C Pro... Aupoko R12 R22 to R134A Conversion Adapter Kit, R12 to R134A Retrofit Valve Fitting Kit for A/C...
9 Wadoy R12 to R134A Conversion Kit, R12 to R134A Adapter, R12 to R134A Retrofit Kit, High/Low AC... Wadoy R12 to R134A Conversion Kit, R12 to R134A Adapter, R12 to R134A Retrofit Kit, High/Low AC...
10 AC Recharge Kit Hose with Gauge, 3 Pack Bullet Piercing Tap Valves, R12 to R134a Conversion Kit for... AC Recharge Kit Hose with Gauge, 3 Pack Bullet Piercing Tap Valves, R12 to R134a Conversion Kit...
11 R12 R22 R502 Screw to R134A Fast Quick Conversion Adapter Switch, Adapter Valve 1/4' to 8v1 Thread,... R12 R22 R502 Screw to R134A Fast Quick Conversion Adapter Switch, Adapter Valve 1/4" to 8v1...
12 Enviro-Safe 3226 Can Tap with Gauge - R-134a can to R-12/R-22 port Enviro-Safe 3226 Can Tap with Gauge - R-134a can to R-12/R-22 port
13 Mudder Bpv31 Piercing Valve 134a Kit R134a Refrigerant Charge Hose with Gauge, Hose Refrigerant Can... Mudder Bpv31 Piercing Valve 134a Kit R134a Refrigerant Charge Hose with Gauge, Hose Refrigerant...
14 QDJUNE R12 to R134A AC Fitting Adapter Kit, R12 to R134a Conversion Kit, R12 R22 to R134A High/Low... QDJUNE R12 to R134A AC Fitting Adapter Kit, R12 to R134a Conversion Kit, R12 R22 to R134A...
15 Wadoy R12 to R134a Conversion Kit, R12 to R134a Adapter,R12 to R134a Retrofit Kit, 1/4' to 7/16'-20... Wadoy R12 to R134a Conversion Kit, R12 to R134a Adapter,R12 to R134a Retrofit Kit, 1/4" to...
16 Measureman Can Tap with Gauge, 20' Hose Refrigerant Recharger with Pressure Gauge, R-134a Can Tap to... Measureman Can Tap with Gauge, 20" Hose Refrigerant Recharger with Pressure Gauge, R-134a Can Tap...
17 Aupoko R1234YF to R134A Low Side Quick Coupler, R1234YF Low Side Quick Coupler, R12 to R134A Hose... Aupoko R1234YF to R134A Low Side Quick Coupler, R1234YF Low Side Quick Coupler, R12 to R134A Hose...
18 ERGAOBOY 4Pcs 90° R12 to R134A High/Low AC Fitting Port Retrofit Conversion Fits for Conditioner... ERGAOBOY 4Pcs 90° R12 to R134A High/Low AC Fitting Port Retrofit Conversion Fits for Conditioner...
19 R134a Charging Hose to Refrigerator - with Gauge - R-134a can to R-12/R-22 Port, Include R12 to... R134a Charging Hose to Refrigerator - with Gauge - R-134a can to R-12/R-22 Port, Include R12 to...
20 Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter Kit Converts R122... Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter Kit Converts...
Bestseller No. 1
InterDynamics Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter Kit...
  • Complete automotive air conditioning conversion adapter kit with 4 adapters
  • Includes one low-side 7/16 inch port, one high-side 3/8 inch port, one high-side for 2-Piece GM port, one high-side 7/16 inch port
  • Fits all cars all years
  • For conversion of R12 to R134a
  • Includes retrofit label
Bestseller No. 2
R12 to R134a Conversion Fitting Adapter Kit - R12 to R134a Retrofit Kit with High/Low Side Fitting,...
  • This retrofit kit allows the conversion of a system running old refrigerant R12 to run on r134a. Replaces R12 with R134a charging port 1/4" SAE or...
  • Wide compatibility: Fits all vehicles 1976 – 1995. Please check the existing valves size to ensure the proper usage.
  • Easy to install: Can be supported used with valve by screw connection.
  • Made of high quality metal and plastic, solid construction for high heat resistance, durability and safety.
  • Package included: high pressure adapter, low pressure adapter, plastic protective cover caps.
SaleBestseller No. 3
R12 to R134A AC Retrofit Fitting Adapter Kit, R12 R22 to R134A High/Low Fitting Port Retrofit...
  • 【WIDE COMPATIBLITY】 - The AC fitting port adapter retrofit r12 to r134a is completely used to replace R12 R22 with R134A charging port 1/4" SAE or...
  • 【PREMIUM QUALITY】 - R12 to R134A retrofit fast conversion adapter kit are made of high quality metal and plastic, solid construction for high heat...
  • 【EASY INSTALLATION】 - R12 to R134A retro fit fittings connect to the thread for use with the valve, there is a removable schrader valves., fitted...
  • 【DIMENSION】 - These Low/High side retrofits/adapters/fittings will convert your old 1/4’’ SAE or 7/16"-20 UNF R12 R22 charging port and make...
  • 【1 YEAR WARRANTY】 - Order R12 R22 Port to R134a quick disconnect valve adapter from Aupoko, we offer 12 months warranty, true worry-free shopping...
Bestseller No. 4
R12 to R134A Conversion Quick Connect Coupler Kit, High/Low Side 90 Degree Angle Quick Coupler...
  • 【WIDE COMPATIBILITY】 - The high/low 90 degree angle side quick coupler with R134A tank adapter are suitable for R134A air conditioner manifold...
  • 【6 BALL STYLE COUPLERS】 - This r134a quick coupler design with 6 ball style, and have a snap lock coupler for quick connect. R134A high side...
  • 【USEFUL TANK ADAPTER】 - This R12 to R134A adapter kit comes with an extra R134A refrigerant tank adapter, 1/2" Female and 1/4" SAE Male, connects...
  • 【PREMIUM QUALITY】 - AC quick connector fittings kit are made of heavy-duty brass for durable using, knurled grip ring for easy, no slip use,...
  • 【1 YEAR WARRANTY】 - This R12 gauge conversion kit with quick couplers comes with 12 months warranty. If the conversion kit fails or any other...
Bestseller No. 5
Micro Traders R-12 to R-134a High Low Side Retrofit Conversion Adapter 1/4 SEA Valves Caps Fitting...
  • [Application]: These Low/High side adapters will convert your old 1/4 SAE or 7/16” R12 charging port and make it accept the R134a quick disconnect...
  • [Material]: Made of high quality metal and plastic, solid construction can be used for a long time.
  • [Type]: This adapters connection size is 1/4SAE x 8mm conversion connector.
  • [Package List]: R12 to R134A A/C retrofit conversion adapter kit contains 1 Pc Low Side Quick Coupler, 1 Pc High Side Quick Coupler, 1 Pc 14mm Blue...
  • [Easy to Use]: Time-saving and labor-saving installation, lightweight,shortcut, as a good choice for car accessory replacement.
Bestseller No. 6
Bullet Piercing Valve Kit with Dust Cap Converts R12 to R134A Fit 7/16 Inch Low Side Port BPV-31...
  • Package includes: you will receive 1 pack BPV-31 kit (including 1 piercing valve, 1 hex key, 1 adapter) and 1 pack universal retrofit valve with a...
  • BPV-31: replace part No.: AP4502525, BPV31D, GPV14, GPV31, GPV38, GPV56, MPV31; compatible with: compatible with 1/4 inch, 5/16 inch, 3/8 inch outside...
  • Universal retrofit valve: the retrofit valve converts from R-12 to R-134a air conditioning system and suit for 7/16 inch low side port; Suit for...
  • Easy to use: BPV-31: just screw it on then it's okay; BPV-31 piercing tap valve: you only need hex key wrench (included) to install this part; Its...
  • Durable material: both of the kit are made of corrosion-resistant metal that won't wear out or rust over time, and anti-leaking design that will be...
Bestseller No. 7
R12 to R134 A High/Low AC Fitting Port Retrofit Conversion Adapter, Quick Coupler Valve A/C 90°...
  • ♥ WIDE COMPATIBILITY - Charging port adapter R12 R22 Port to accept R134a Quick Disconnect. These Low/High side retrofits/adapters/fittings will...
  • ♥ PREMIUM QUALITY - With solid copper material, resistant to corrosion & good extensibility.
  • ♥ EASY INSTALLATION: The low AC fitting conversion adapter with time-saving and effort-saving while installing, lightweight, shortcut.
  • ♥ DIMENSION - Low Side, 1/4"SAE (7/16''- 20) x 13 mm, blue. High Side, 1/4" SAE (7/16’’- 20) x 16 mm, red.
  • ♥ WARRANTY - This can tap comes complete with a lifetime warranty. If the dispensing valve fails, simply contact us for a replacement or full...
Bestseller No. 8
Aupoko R12 R22 to R134A Conversion Adapter Kit, R12 to R134A Retrofit Valve Fitting Kit for A/C Pro...
  • WIDE COMPATIBLITY - Completely used to replace R12 with R134A charging port adapter, perfect air conditioning conversion adapter kit.
  • PREMIUM QUALITY - Made of stainless steel and plastic, solid construction for high heat resistance, durability and safety.
  • EASY INSTALLATION - Connected to the thread for use with the valve, there is a gas valve inside, fitted with a plastic protective cover, easy and fast...
  • NOTE - These Low/High side retrofits/adapters/fittings will convert your old 1/4" SAE R12 R22 charging port and make it accept the R134a quick...
  • 1 YEAR WARRANTY - Order R12 R22 Port to accept R134a quick disconnect from Aupoko, we offer 12 months warranty, true worry-free shopping experience....
Bestseller No. 9
Wadoy R12 to R134A Conversion Kit, R12 to R134A Adapter, R12 to R134A Retrofit Kit, High/Low AC...
  • R12 to R134A Conversion Kit: Quick coupler, charging port adapter. Our Low and High side fittings will convert your old 1/4" SAE or 7/16’’- 20UNF...
  • Easy to install, save time and effort, can be supported used with valve by screw connection. Lightweight and shortcut.
  • Made of high quality brass alloy material to last under extreme conditions and for high heat resistance durability and safety.
  • The high side is 1/4" SAE(7/16"-20)x16mm; The low side is 1/4"SAE(7/16"-20)x13mm
  • Can be matched used with a valve by connecting with screw thread There are gas valves inside, equipped with a plastic protective cap.
Bestseller No. 10
AC Recharge Kit Hose with Gauge, 3 Pack Bullet Piercing Tap Valves, R12 to R134a Conversion Kit for...
  • UNIVERSAL AC RECHARGE HOSE WITH GAUGE - One end with a valve connects to the can with 1/2 trapezoidal thread, and the other end connects to the car's...
  • QUALITY MATERIAL & DURABLE - The hose is made of quality rubber with high-pressure resistance. The copper valve is durable to use.
  • USER-FRIENDLY – The 90-Degree push and lock coupler features an auto shut-off function. The built-in safety valve to prevent accidental venting of...
  • UNIVERSAL CONVERSION VALVE – Comes with a conversion valve which is used to convert from R-12 to R-134A air conditioning system. Can be screwed on...
  • COMPLETE KIT - Package Includes: 3 x Bullet Piercing Tap Valves; 1 x R134a Charging Hose with Gauge; 1 x Universal Conversion Valve; 1 x Dust Cap; 3 x...
Bestseller No. 11
R12 R22 R502 Screw to R134A Fast Quick Conversion Adapter Switch, Adapter Valve 1/4" to 8v1 Thread,...
  • 【WIDE COMPATIBILITY】 Retrofit valve adapter for automotive air conditioning refrigerant systems converting from R12, R22, R502 to R-134A.
  • 【PREMIUM QUALITY】 The R12 R22 R502 to R134A fast quick conversion is made of high quality brass alloy material to last under extreme conditions...
  • 【EASY INSTALLATION】 Easy to be installed, save time and effort, can be supported used with valve by screw connection.
  • 【GOOD PERFORMANCE】 With 15-80 Centigrade temperature resistance, and high Working pressure, rustproof, long lifetime.
  • 【1 YEAR WARRANTY】 Order R12 R22 R502 to R134A retrofit valve from Aupoko, we offer 1 YEAR WARRANTY, true worry-free shopping experience. If this...
Bestseller No. 12
Enviro-Safe 3226 Can Tap with Gauge - R-134a can to R-12/R-22 port
  • R-134a Can to R-12/R-22 service port connection
  • 20" long hose
  • End fits R12, 22, 502 fittings
  • Gauge has scale readings for R134, R12, & 22
Bestseller No. 13
Mudder Bpv31 Piercing Valve 134a Kit R134a Refrigerant Charge Hose with Gauge, Hose Refrigerant Can...
  • Package content: 3 packs BPV-31 piercing tap valve kits (each kit contains 1 piercing valve, 1 hex key and 2 adapters), including R134a U-charge hose...
  • Easy to install: our BPV-31 piercing tap valve kits come in compact design that only requires a 2-inch clearance area for installation and use, and...
  • R134a Charging hose: 19 inch hose with R-134a can to R-12/R-22 service port connection, 1/2 inch end fits R12, 22, 502 fittings; And the gauge has...
  • Replace model of BPV-31 piercing tap valve: AP4502525, BPV31D, GPV14, GPV31, GPV38, GPV56, MPV31; Compatible with 1/4 inch, 5/16 inch, 3/8 inch...
  • Universal retrofit valve: the retrofit valve converts from R-12 to R-134a air conditioning system and suit for 7/16 inch low side port; Suit for...
Bestseller No. 14
QDJUNE R12 to R134A AC Fitting Adapter Kit, R12 to R134a Conversion Kit, R12 R22 to R134A High/Low...
  • [PACKING] These Low/High side /adapters/fittings will convert your old 1/4" SAE or 7/16"-20 UNF R12 R22 charging port and make it accept the R134a...
  • [INSTALLATION] R12 to R134A retro fit fittings connect to the thread for use with the valve, there is a removable valves, fitted with a plastic...
  • [QUALITY] R12 to R134A fast conversion adapter kit, Durable material: both of the kit are made of corrosion-resistant metal that won' t wear out or...
  • [COMPATIBLITY] The AC fitting port adapter r12 to r134a is completely used to replace R12 R22 with R134A charging port 1/4" SAE or 7/16"-20UNF...
  • [LIFT-TIME WARRANTY] pursue outstanding quality and service, If you are not satisfied with this product or if you have any question, please feel free...
Bestseller No. 15
Wadoy R12 to R134a Conversion Kit, R12 to R134a Adapter,R12 to R134a Retrofit Kit, 1/4" to 7/16"-20...
  • 【Great Adapter】: R12 to R134a conversion adapter kit, quick coupler.Complete automotive air conditioning conversion adapter kit with 4 adapters
  • 【Thread】: Low Side, 1/4’’(7/16’’- 20) x 13 mm (Blue). High Side, 1/4’’(7/16’’- 20) x 16 mm (Red).
  • 【Easy To Install】: Save time and effort, can be supported used with valve by screw connection.for conversion of R12 to R134a.
  • 【Premium Quality】: Made of high quality aluminum alloy material to last under extreme conditions and for high heat resistance durability and...
Bestseller No. 16
Measureman Can Tap with Gauge, 20" Hose Refrigerant Recharger with Pressure Gauge, R-134a Can Tap to...
  • For R134A R12 or R22 refrigerant to use for home air conditioning and auto-air conditioning add refrigerant.
  • 2-3/4" Dial size, Blue case, polycarbonate window, brass inside and connection, vibration proof dashpot movement
  • Pressure range:-30inHg-0-120psi/bar retarded to 350psi in white scale, R22 in green, R12 in red, R134A in blue, pointer micro-adjustable, Accuracy:...
  • 20" length blue hose, working pressure 600psi, burst pressure 3000psi
  • R-134a Can Tap To R-12/R-22 1/4" Female Port
Bestseller No. 17
Aupoko R1234YF to R134A Low Side Quick Coupler, R1234YF Low Side Quick Coupler, R12 to R134A Hose...
  • ❄ WIDE COMPATIBILITY ----- This R1234YF to R134A low side quick coupler fits for R1234YF/R12 to R134A car air-conditioning AC charging.
  • ❄PREMIUM QUALITY ----- R134A to R1234YF adapter is a perfect fit adapter which is made of solid premium aluminum with good quality and strong...
  • ❄ EASY INSTALLATION ----R1234YF A/C low pressure line to adapt your R134A adapter with auto shut off, easy and convenient to use.
  • ❄ SIZE DETAIL ----- R1234YF to R134A adapter: Low side R1234yf coupler 14 mm female x 1/4’’ SAE male. R12 to R134a Adapter: 1/4’’ SAE female...
  • ❄ 1 YEAR WARRANTY ----- Order r1234yf quick couplers from Aupoko, we offer 1 YEAR WARRANTY, should be there any question, please feel free to...
Bestseller No. 18
ERGAOBOY 4Pcs 90° R12 to R134A High/Low AC Fitting Port Retrofit Conversion Fits for Conditioner...
  • Size: 1/4" SAE (7/16"-20) x 16 mm,High Side (Red).1/4" SAE (7/16"-20) x 13 mm,low side (blue).
  • Excellent Quality: Solid brass construction for maximum strength and durability.
  • Great Airtightness: The adapter can ensure that the joint will not leak during use.
  • Wild applications: The adapter is suitable for the most air conditioners on the market.
  • Quick Installation: Easy to install and connect, can quickly applied to the AC system
Bestseller No. 19
R134a Charging Hose to Refrigerator - with Gauge - R-134a can to R-12/R-22 Port, Include R12 to...
  • Package Includes: R134a Charging Hose - With Gauge X 1pcs, R12 to R134a Adapter (4 Pieces ) X 1 Set, BPV31 Piercing Valve X 1 Set
  • R134a Charging Hose : 19" long, Only used for Home Refrigerator adding refrigerant, Come with gauge for easily viewing during use, connect to the...
  • R12 to R134a Retrofit Kit : One low side port and one high side port, Completely used to replace R12 with R134a, made it easy to convert an R12 system...
  • BPV31 Piercing Valve ( Not OEM)for HVAC System, 3-In-1 Line Tap Piercing Valve for Bullet, Fits 3 sizes of tubing: 1/4", 5/16" and 3/8", include: 1...
  • For more product details, please see the picture on the left side of the product text description. Please read the product details carefully before...
SaleBestseller No. 20
Certified A/C Pro Car Air Conditioner Adapter Kit, Complete AC Conversion Adapter Kit Converts R122...
  • Complete air conditioning conversion adapter kit with 2 adapters
  • One low side .44 inch port and one high side .38 inch port
  • For pre-1976 vehicles and some late model imports
  • For conversion of R12 to R134a
  • Includes retrofit label

Having trouble finding a great r12 to r134a?

This problem is well understood by us because we have gone through the entire r12 to r134a research process ourselves, which is why we have put together a comprehensive list of the best r12 to r134as available in the market today.

After hours of searching and using all the models on the market, we have found the best r12 to r134a for 2023. See our ranking below!

How Do You Buy The Best R12 To R134a?

Do you get stressed out thinking about shopping for a great r12 to r134a? Do doubts keep creeping into your mind?

We understand, because we’ve already gone through the whole process of researching r12 to r134a, which is why we have assembled a comprehensive list of the greatest r12 to r134a available in the current market. We’ve also come up with a list of questions that you probably have yourself.

John Harvards has done the best we can with our thoughts and recommendations, but it’s still crucial that you do thorough research on your own for r12 to r134a that you consider buying. Your questions might include the following:

  • Is it worth buying an r12 to r134a?
  • What benefits are there with buying an r12 to r134a?
  • What factors deserve consideration when shopping for an effective r12 to r134a?
  • Why is it crucial to invest in any r12 to r134a, much less the best one?
  • Which r12 to r134a are good in the current market?
  • Where can you find information like this about r12 to r134a?

We’re convinced that you likely have far more questions than just these regarding r12 to r134a, and the only real way to satisfy your need for knowledge is to get information from as many reputable online sources as you possibly can.

Potential sources can include buying guides for r12 to r134a, rating websites, word-of-mouth testimonials, online forums, and product reviews. Thorough and mindful research is crucial to making sure you get your hands on the best-possible r12 to r134a. Make sure that you are only using trustworthy and credible websites and sources.

John Harvards provides an r12 to r134a buying guide, and the information is totally objective and authentic. We employ both AI and big data in proofreading the collected information.

How did we create this buying guide? We did it using a custom-created selection of algorithms that lets us manifest a top-10 list of the best available r12 to r134a currently available on the market.

This technology we use to assemble our list depends on a variety of factors, including but not limited to the following:

  1. Brand Value: Every brand of r12 to r134a has a value all its own. Most brands offer some sort of unique selling proposition that’s supposed to bring something different to the table than their competitors.
  2. Features: What bells and whistles matter for an r12 to r134a?
  3. Specifications: How powerful they are can be measured.
  4. Product Value: This simply is how much bang for the buck you get from your r12 to r134a.
  5. Customer Ratings: Number ratings grade r12 to r134a objectively.
  6. Customer Reviews: Closely related to ratings, these paragraphs give you first-hand and detailed information from real-world users about their r12 to r134a.
  7. Product Quality: You don’t always get what you pay for with an r12 to r134a, sometimes less, and sometimes more.
  8. Product Reliability: How sturdy and durable an r12 to r134a is should be an indication of how long it will work out for you.

John Harvards always remembers that maintaining r12 to r134a information to stay current is a top priority, which is why we are constantly updating our websites. Learn more about us using online sources.

If you think that anything we present here regarding r12 to r134a is irrelevant, incorrect, misleading, or erroneous, then please let us know promptly!

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FAQ:

Q: Can I use R12 instead of R134a?

A: Now in order to abide by the law, the cars manufactured before 1995 needed to have a refrigerant conversion from R12 to R134a, which also led to further complexities. As R12 used a different oil that was not fit to be used with R134a, the replacement was not that simple. But if your R12 system is working well and not leaking, you can still use it.

Q: What is R134a refrigerant used for?

A: The refrigerant R134A is called tetrafluoroethane and is classified as one of the HFC gases from the other refrigerant variants. Today, R134A is commonly used in vehicle air conditioning systems, but it can also be used in refrigerators, freezers and other refrigeration equipment similar to R12.

Q: What parts do I need to convert my car to R134a?

A: Necessary parts for conversion: Compatible AC compressor AC flush kit / AC service unit Green O rings for the R134A R134A port adapters R134a high-pressure and low-pressure switches R134A compatible accumulator dryer Orifice tube New hoses compatible with R134A (If the vehicle is older than -1990) …

Q: How much R134a do I need for my application?

A: Comparatively, larger R134a molecules should take more space, and a smaller amount might be required. You can use the R134a retrofit capacity chart for this purpose. Generally, the new amount is 75-85% of the quantity advised by the manufacturer.