If you want to see larger or smaller text,
press Ctrl & +/- keys,
or Ctrl & mousewheel.

Derek Osgood Motor Care logo
Air Con

A vehicle air-conditioning unit is basically a refrigeration system ....which moves the heat from inside the vehicle, pushes it to the outside and supplies cooler air inside.

There are a number of components to an air-con system:
  • compressor, which compresses and circulates the refrigerant
  • condenser, which changes the phase of the refrigerant and expels heat removed from the car
  • expansion valve, or orifice tube in some vehicles, which reduces the pressure of the refrigerant liquid, meters its flow and atomizes it
  • evaporator, which transfers heat to the refrigerant from the air blown across
  • receiver or dryer, which functions as a filter for the refrigerant/oil, removing moisture and other contaminants
The refrigerant is pressurised by the compressor and passes it to the condensing coils.  Compressing a gas makes it hot. Once in the condenser, the extra heat and the heat the refrigerant collected in the evaporator is lost to the air flowing across it from outside the vehicle. Once cooled, it changes from a gas back into a liquid.  The liquid then passes through the expansion valve to the evaporator, (the condensing coils) inside the vehicle, where it loses pressure that was added to it in the compressor. The pressure reduction causes some of the liquid to change to a low-pressure gas as it cools the remaining liquid. This two-phase mixture enters the evaporator, and the liquid portion of the refrigerant absorbs the heat from the air across the condensing coils and evaporates. The vehicle's fan circulates air across the cold evaporator and into the interior. The refrigerant is pumped around the system continuously in this way.

We check your air con to ensure it functions properly as a number of things can, and do, go wrong with air con systems.  You can keep yours in good order by contacting us or booking online now.

* * *


click to enlarge air-con diagram
click to enlarge
air-con diagram
Opening hours:
8am - 5pm
Mon - Fri
Air Con
 air-con   booking   contact   feedback  home   links   location   MOTs   offers   photos   services   sitemap   testimonials   tips 
Bookmark and Share
 << back   fwd >>