Did you know that a correctly maintained air conditioning system traps all pollen and dust, delivers good clean pure air, increases passenger comfort and keeps the driver alert?
The big pollen season is coming up, the weather is warming too…..keep calm, stop sneezing….don’t be caught out and relax……
Irritability behind the wheel is much more noticeable in hot weather, opening the windows makes it worse, uses more fuel, the buffeting is tiring and not the answer.
There is more to how your air conditioning works than most people think…..it needs looking after so it can look after you….
Read on for more information…….
We all take air conditioning now for granted now, but it is a fairly complex system.
In simple terms, it is heat exchanging and only conditioning the air we breath into something we like, increasing passenger comfort and assisting the driver in staying more alert.
Only one degree either side of our body temperature will affect our ability to concentrate, remain calm and stop fidgeting around behind the wheel.
Humans can deal with dry heat, however we do not like too much humidity, typically an ambient temperature of 21c with around 40% humidity is comfortable for us. ( think warm cup of tea )
HOW DOES IT WORK ?
Well……..a compressor ( pump) driven by the engine will compress and heat refrigeration gas around a sealed system ( illustrated ) then as this gas is drawn into a heat exchanger behind your dashboard, through various coolers and a drier ( to remove moisture and contamination) it is eventually stopped by a valve which will open and shut periodically, finally allowing the vapour into a large chamber ( evaporator ) located behind your dashboard, where it is allowed to expand and cool, the chamber absorbs the heat, but more importantly the humidity from the cabin through the metal fins on its exterior…..still awake ? ……
When the fan is turned on inside the car, it will deliver pure fresh air, bacteria, pollen and dust free.
We can regulate the amount of heat with the red and blue dials on manual refrigeration, this is usually found on less expensive vehicles, it’s the same principal as climate control but managed in a different way.
On a fully automatic system ( climate control ) numbers will be displayed in Celsius, sensors around the vehicle detect exact temperatures, and will move the airflow around through the different vents to eliminate hot or cold spots, a manual system will rely on the driver to change the airflow direction.
The re-circulation button should remain in the ‘ off ‘ position except to cool the vehicle quickly or to eliminate the intake of fumes or dust. Recirculated air is not particularly healthy, fresh air should flow.
Most of us have fridges, they require no maintenance, it’s plug and go….or not. The difference is that all the pipes that carry gas are welded, typically a fridge will not move and is not subject to vibration or big changes in the temperature around it.
Cars are different, they have pipes that are joined together with nuts and bolts, sealed with flimsy rubber rings and exposed to lots of vibration with temperature changes. Components expand and contract, refrigeration loss is inevitable. Up to 10% a year is typical, 15% is not uncommon.
The compressor ( pump) is the heart of the system. It is a finely tuned instrument that needs refrigeration oil to function.
Think of it as you would your own heart, without the right food at the right time and a reasonable amount of exercise, how long would we last ?.
A 10% loss of nutrition will reduce the life of a compressor by 40%.
All manufacturers insist on refrigeration gas servicing at least every two years and maybe less or more, depending on where and how the vehicle is used.
We recommend 18 months for most vehicles as adequate, although all our own vehicles are looked at every six months, as we understand the consequences of not doing so, and would rather not be taking the system apart to fix something we would rather not fix, we call it preventative maintenance.
This is only a question, but do you change your oil when it should be changed or do you wait for the engine to knock first ? Its the same principal.
WHAT DOES A SERVICE INVOLVE ?
We connect the sealed system to a refrigeration service station and draw out the balance of what is in there, the machine weighs it and we then compare the figure with what should be in there.
All refrigeration weights are set by the manufacturer.
The system is then purged to remove all moisture and contamination, typically this evacuation will contain tiny rubber and metal particles lost from the aging components, we also need to create a vacuum, a zero moisture content is also essential as moisture is water, it is not possible to compress water only gas.
When we are happy ( this happens sometimes ) the system is charged with exactly the right amount of refrigeration gas and an oil unique to air conditioning systems.
The cabin filter is cleaned or replaced and if necessary, and always with the customers consent, an anti bacterial treatment is applied to the interior, this zero’s bacteria and and residual odours, sterilising the airflow ducts, carpets and seats, we’ve used it for years and it’s amazing, the most common comment is ‘ my car smells like a new car’. ( illustrated )
There is always a build up of bacteria in vehicles whether we like it or not, this is caused for a number of reasons, although usually we only have ourselves to blame…..sorry
When this is all done, we run up the air conditioning and test the face vents with a thermometer, the really exciting bit is when we see the reading moving between 3-5c, much less and it risks a freeze, this is not good, freezing cracks metal pipes, much more and something is wrong.
COMMONLY ASKED QUESTIONS:)
“Can I do it myself”?.
– No, it is against the law in Europe and also as refrigeration gas is a hazardous material, a life changing accident is likely. All handlers of hazardous materials should be qualified to do so and use personal protective clothing and eyewear as the unexpected can happen.
“Can I use another cheaper gas”?.
– No, it will blow the front of your car off.
“What will happen if I just leave it as it seems to be working”?.
– You can but in the same way your Mother said ‘ if you carry on doing that there will be tears ‘ there will be tears, a broken system is inconvenient at best and will cost a lot of money to fix.
“I know there is a leak why can’t I just have it ‘ topped up”?.
– Firstly, there is no such thing as ‘ topping up’, all systems require a specific weight to operate correctly. Unless we know what is in there we do not know how much to add.Too much is as harmful as too little. Also by adding to a depleted system without purging first we are trapping moisture in there, the mixture of refrigeration gas and moisture is corrosive and potentially explosive. It’s cheaper and better to do the job properly.
“I have an old car with old gas, can you help “?.
– Yes, we need to evaluate your car properly first, piling new gas into an old system may make it work, although not usually for very long. The pump and hoses were designed to run on a much thicker gas, it is only a matter of time before a hole appears, each case is different so call us.
Thanks to Auto & Aviation Climate Control Care, for all this interesting information.