A/C that cools like day one
Mercedes-Benz climate control (THERMOTRONIC) is a precise multi-zone system of sensors and motorised flaps — there is no such thing as a rough top-up here. At our workshop in Radiofar (Belgrade), right next to the E-75 highway, A/C service follows the factory procedure:
- Vacuum and refill to the exact gram — the factory refrigerant and PAG oil quantity by VIN and the vehicle label
- We work with both R134a and the newer R1234yf gas (mandatory on models from ~2015)
- Leak detection with UV dye and pressurised nitrogen — condenser, lines, evaporator, compressor
- Ozone evaporator disinfection plus professional foam — removes bacteria and bad odours
- Activated-carbon cabin filter replacement (OEM quality)
- Compressor, magnetic clutch and condenser checks, pressure readings on both circuits
- THERMOTRONIC diagnostics via XENTRY — temperature sensors, motorised flaps, actuators, calibration
R134a or R1234yf — it matters
| Gas | Application | Note |
|---|---|---|
| R134a | models up to ~2015 | Standard — widely available |
| R1234yf | models from ~2015 | Mandatory per EU rules — pricier, must never be mixed with R134a |
Mixing gases or filling the wrong quantity destroys the compressor — the most expensive part of the system. We fill only the gas prescribed for your vehicle, weighed to the gram, with the exact PAG oil quantity.
Bad smell from the vents?
A musty smell when the A/C starts means bacteria and fungi have built up on the evaporator — the surface all your cabin air passes through. The fix is ozone and foam disinfection applied directly to the evaporator plus a new activated-carbon cabin filter. It takes 30 minutes and is recommended once a year, ideally before summer.
Webasto and auxiliary heating
Many Mercedes models carry a factory Webasto auxiliary heater — and its failure is a common hidden cause of a drained battery and stored faults. We diagnose and service the dosing pump, burner and timer, with activation through XENTRY.
FAQ — air conditioning
How often should the A/C be regassed?+
A system naturally loses 5-10% of its gas per year, so a check and top-up every 2 years is recommended. If the A/C weakens within months, there is a leak — we find it with UV dye or pressurised nitrogen, because refilling without fixing the leak is money wasted.
The A/C cools poorly — what is the usual cause?+
Most often low gas or a dirty condenser; on newer models also THERMOTRONIC flaps. We measure pressures on both circuits and vent temperatures — in 30 minutes you know the exact cause and price.
Bad smell when I turn the A/C on?+
Bacteria and fungi on the evaporator. The fix: ozone and foam disinfection applied directly to the evaporator plus a new activated-carbon cabin filter. 30 minutes, recommended yearly.
Which gas does my Mercedes take — R134a or R1234yf?+
Models up to ~2015 use R134a; newer ones must use R1234yf. The gases must never be mixed — we verify the type and exact quantity by VIN and the factory label before filling.
Do you service Webasto auxiliary heaters?+
Yes — diagnostics and service of the Webasto system, dosing pump and burner. A faulty Webasto is a common hidden cause of an overnight-drained battery.