As temperatures continue to rise, many Mercedes owners are discovering that their air conditioning systems are no longer cooling as effectively as they once did. Recently, we welcomed a Mercedes CLS320 into our workshop after the owner noticed that the air conditioning was struggling to keep the cabin cool, particularly during longer journeys and while sitting in traffic.
Following a full inspection of the climate control system, we identified the cause: the refrigerant level had dropped below the manufacturer's specification, reducing the system's cooling efficiency.
Fortunately, no major faults were found, and a professional air conditioning regas combined with a complete system health check quickly restored performance.
Even in well-maintained vehicles like the Mercedes CLS320, refrigerant gas naturally escapes over time through seals, pipe connections and system components.
This gradual loss can reduce cooling performance long before the system stops working completely.
Common signs your Mercedes CLS320 may need an air conditioning service include:
Before recharging the system, we carried out a full inspection using our professional air conditioning service station.
The vehicle was connected to our diagnostic equipment, allowing us to measure both high and low-side pressures.
The readings confirmed that refrigerant levels were lower than Mercedes-Benz specifications, explaining the poor cooling performance experienced by the customer.
Before adding new refrigerant, the system underwent a vacuum test for over 20 minutes.
This important procedure removes moisture from the air conditioning system and helps identify potential leaks.
The CLS320 passed the test successfully, indicating that the system remained fully sealed.
Once the system integrity was confirmed, we recharged the air conditioning system with the correct quantity of refrigerant specified by Mercedes-Benz.
As part of the service, we also added:
These steps help protect internal components while making future diagnostics easier if required.
Following the regas procedure, we tested the climate control system under operating conditions.
Within minutes, vent temperatures dropped significantly, producing cold air at approximately 5°C from the centre vents.
System pressures remained stable and all climate control functions operated exactly as intended.
The customer immediately noticed the improvement in cabin comfort and cooling performance.
Many vehicle owners only think about their air conditioning when it stops working.
However, refrigerant naturally decreases over time, which can place additional strain on the compressor and other system components.
Regular servicing helps:
We recommend an air conditioning inspection and regas every two years for optimum performance.
As part of the service, we also checked the cabin pollen filter.
A blocked filter can reduce airflow and make the air conditioning system appear less effective, even when cooling performance is normal.
The filter on this CLS320 remained in good condition, but we advised replacement during the next scheduled service interval.
At Pitair Motors, we provide professional air conditioning servicing, diagnostics and repairs for Mercedes-Benz vehicles and other German marques.
Our services include:
Using specialist equipment and manufacturer-approved procedures, we ensure your air conditioning system performs exactly as it should.
If your air conditioning isn't performing as well as it used to, don't wait until it stops working completely.
A simple system inspection and regas can often restore performance and help prevent more expensive repairs later on.
✅ Mercedes-Benz specialists
✅ Full air conditioning system checks
✅ UV leak detection included
✅ Fast turnaround service
✅ Professional climate control diagnostics
Contact Pitair Motors today to book your Mercedes CLS320 air conditioning regas and system check.
