How much refrigerant is in your car’s air con?
Every car air con system has its own refrigerant capacity in grams, set by the manufacturer. Here you can read where to find that figure for your car, why a technician fills by weight and what happens when there is too little or too much refrigerant in the system.
By the team at Autobedrijf Willemsbrug, RDW-approved APK (MOT) test station since 1979 · Updated 4 November 2026
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The short answer
The amount of refrigerant differs from car to car and is shown in grams on a sticker under the bonnet. Kia owner’s manuals, for example, list amounts from 450 to 850 grams of R1234yf, each with a tolerance of 25 grams. That is why a technician fills the system by weight with an air con service machine, and not by pressure or by feel. According to MAHLE, an air con system can lose up to 10% of its refrigerant a year.
How many grams of refrigerant does a car need?
A passenger car has a few hundred grams of refrigerant in its air con. Refrigerant is the gas that carries heat out of the car in a closed circuit. The manufacturer sets the amount for each model and each version. So two cars of the same make can need different amounts.
The examples below come from Kia owner’s manuals. They show how large the differences are, even within one model.
| Example from the manual | Refrigerant | Refrigerant capacity | Compressor oil |
|---|---|---|---|
| Kia, 2026 owner’s manual (United States) | R1234yf | 450 ± 25 grams | 120 ± 10 grams of PAG oil |
| Kia EV6 without heat pump | R1234yf | 750 ± 25 grams | 180 ± 10 grams of POE oil |
| Kia EV6 with heat pump | R1234yf | 850 ± 25 grams | 180 ± 10 grams of POE oil |
| Kia EV6 without heat pump | R134a | 800 ± 25 grams | 180 ± 10 grams of POE oil |
| Kia EV6 with heat pump | R134a | 900 ± 25 grams | 180 ± 10 grams of POE oil |
Source: Kia owner’s manuals. The EV6 manual is the edition for India, with one version on R134a and one on R1234yf. In Europe, new cars usually have R1234yf, sometimes R744. For your own car, only the sticker under the bonnet counts.
Three things stand out. In this example a car with a heat pump needs 100 grams more refrigerant, because the heat pump uses the same circuit with extra pipes and valves. The R1234yf version needs 50 grams less than the R134a version. And the tolerance is 25 grams in every case. At 450 grams that is about 6%, at 850 grams about 3%. That shows how accurate the fill has to be.
Where can you find the refrigerant capacity of your car?
The refrigerant capacity is on a sticker on the inside of the bonnet. Kia writes in its manual that this label also shows which refrigerant your car uses. On other makes the sticker is often in the same place, or near the bonnet catch or the radiator. This is how to read it:
- Open the bonnet and look for a sticker with the text R-134a or R-1234yf, often with a warning symbol.
- Read the type of refrigerant. R-134a is mainly found in older cars, R-1234yf in most cars from 2017 onwards.
- Read the amount. It is given in grams (g) or kilograms (kg), often with a tolerance, for example 550 ± 25 g or 0.55 ± 0.025 kg.
- Look at the oil. The sticker often also shows the type of compressor oil, for example PAG or POE, sometimes with the amount.
- No sticker, or you cannot read it? Call us with your registration number. We will look up the details for you.
The Dutch registration certificate (kentekenbewijs) does not show the refrigerant. Not sure which refrigerant your car has? Read R134a or R1234yf: which refrigerant does your car use.
Why does a technician fill by weight and not by pressure?
A technician fills the air con by weight, because the pressure in the system tells you little about the amount. When the air con is switched off, the refrigerant is partly liquid and partly gas. The pressure then depends mainly on the temperature and hardly on the amount. On a warm day the pressure in a half-empty system is higher than in a full system on a cold day.
A DIY recharge kit with a small gauge on the can only measures that pressure. So it cannot tell you how much refrigerant is already in the system. An air con service machine in the workshop recovers the old refrigerant and weighs it. It then puts the specified amount back in, measured on a set of scales.
A little compressor oil comes out with the old refrigerant. The technician replaces that amount with the oil the manufacturer specifies. An electric compressor needs oil that insulates against electricity, usually POE oil. The manufacturer decides which oil is used.
What happens with too little or too much refrigerant?
Too little and too much refrigerant are both bad for the air con. Kia writes in its manual that too little refrigerant reduces the cooling capacity, and that too much also has a negative effect on how the system works.
| Effect | Too little refrigerant | Too much refrigerant |
|---|---|---|
| Cooling | The air con cools less, especially on hot days and in traffic. | The air con often cools worse as well, because the condenser cannot get rid of the extra heat. |
| Compressor | The refrigerant carries the oil round the system. With too little refrigerant, less oil reaches the compressor and it is lubricated less well. | The pressure on the high-pressure side rises. That puts extra strain on the compressor and the seals. |
| What you notice | It takes longer before the air feels cool. The compressor switches on and off more often. | The pressure sensor can switch the compressor off. The cooling then cuts out now and then. |
| Usual cause | Slow loss over the years, or a leak. | Topping up without knowing how much was still in the system, for example with a DIY can. |
Sources: Kia owner’s manual (cooling capacity and negative effects) and the ANWB (lubrication through the refrigerant). The other points are workshop knowledge.
The ANWB (the Dutch motoring organisation) writes that the circulation of the refrigerant also lubricates the compressor, and that an air con that runs dry will break down. Is your air con cooling less well? Read car air con not cold or blowing warm air. Has it stopped working altogether? Read car air con not working.
How much refrigerant does an air con lose each year?
According to MAHLE, an air con system can lose up to 10% of its refrigerant a year. A small loss through hoses and seals is normal, even when there is no real leak.
An example: with 500 grams, 10% is 50 grams in the first year. If it carries on like that every year, about a third can be gone after four years. That is an upper limit. In many cars the loss is slower.
According to the ANWB, the refrigerant needs topping up on average once every 4 to 6 years. So have the air con checked every year. If it cools less well, an air con service is needed. Which maintenance is due when is set out in our car air con maintenance schedule (in Dutch).
Why does the price of an air con service depend on the amount?
The price of an air con service depends on the amount, because the refrigerant itself is a large part of the cost, especially with R1234yf. A car that needs 850 grams gets more refrigerant than a car that needs 450 grams. That is why garages often quote a starting price.
If you compare prices, ask whether the price covers the full refrigerant capacity of your car. Also ask whether recovering, vacuuming and checking that the system is sealed are included. With us we tell you in advance what the air con service costs for your car, based on its registration number. What happens during the service is explained on our page about an air con regas in Rotterdam.
How we fill your air con to the gram
In our workshop in Rotterdam-IJsselmonde, an air con service goes like this:
- We use your registration number to look up the refrigerant, the capacity and the oil, and we check these details against the sticker.
- The air con service machine recovers the refrigerant and weighs it. The difference from the specified amount shows how much has been lost.
- We put the system under vacuum. That removes air and moisture. At the same time we see whether the system holds the vacuum.
- If the system holds the vacuum, we add the oil and the specified amount of refrigerant by weight.
- We check how the system works by measuring the pressures and the temperature of the air from the vents.
- If the system does not hold the vacuum, we do not top it up blindly. We first look for the leak with a nitrogen test and UV dye where needed. We tell you in advance what the repair costs, and we only carry out repairs once you have agreed.
Our technicians hold an F-gas certificate for R134a and R1234yf. Does your car use R744 (CO2)? Then call us first with your registration number. Everything about our air con service and repairs is on our page about car air conditioning in Rotterdam.
Read more
Frequently asked questions
Sources
- Kia: EV6 Manual: Air conditioning system (refrigerant and compressor lubricant)
- Kia: Owner’s manual 2026: Air conditioning system (specifications)
- Kia: Owner’s manual: Checking the amount of refrigerant and compressor lubricant
- MAHLE Aftermarket: AC-check flyer: refrigerant loss of up to 10% a year (in Dutch)
- ANWB: Airco en onderhoud (in Dutch, consulted November 2026)