March 2021

A s you stand in the workshop, freezing you knuckles off (yes, I said “knuckles” – what did you think you read?) in the depths of winter, it’s probably hard to remember that in just a few months, customers will be surging into your garage reception, dripping profusely with sweat. At the moment, the last thing anyone really wants is colder air. However, once we hit June, you will see them start to panic if that little snowflake button doesn’t work. This month the conversation is on air conditioning systems, if you did not guess that already, and the do's and don’ts when it comes to recharging the system. Of course, A/C systems can go wrong at any time of year, so maybe it’s worth having a recharge around the topic, before the mad rush starts again. To help me with this, I have enrolled Martyn Henderson, our invaluable Master Technician. What are the most important things to remember when carrying out an A/C recharge? “The very first thing that must be done is to ask the customer questions regarding the car’s air conditioning system. This means when was it last recharged and when was it last working. If it’s not working now, ask if there has been any damage caused at any point in the car’s history. Basically, you need to interrogate the customer. “Next, it’s an obvious one; Remember all your protective equipment. You only have one pair of eyes; you only have one pair of hands. You need to look after them! Then it is imperative that you check the hoses, making sure they have been cleared of the previous re-gas, you don’t want any false readings on the machine when you’re checking for pressure. Before you even hook the machine up, you’ll also want to clarify that you hear/ see the pump for the air con kicking into life, as this is a dead giveaway that the system is working or not. Once the machine is hooked up correctly start the car and check that the high-pressure gauge ascends, and the low -pressure gauge descends. However. Probably the most important thing, if there's no gas in there, do not recharge the system and send the car out on its merry way. No gas, no re-gas, no recharge, no charge.” What are the most common causes of air-con failure? “The majority of air-con systems hold the gas very comfortably for a minimum of two years. This is one of the reasons why we tell our customers that a re-gas/service must take place every two years. Every car can lose gas over time, the key question is at what rate it will dissipate. “Just like a car can lose a drop of oil over its life, nothing is perfect. I once had a customer with a Toyota Celica where the air-con system wasn’t working as it should. The customer told me that he had owned the car for about around five years and never even knew you even had to recharge it. In my career I have replaced a large number of air-con compressors. I have replaced many pressure switches too. Once this fails, it stops the whole system from working, a failsafe if you will. This makes the pressure switch a crucial part of the system. However, I would say that the single most common cause of failure is the condenser. This is because its situated at the very front of the car, and this means it takes all the hammering, all the stones and all the rubbish.” Thanks to Martyn for his input. In conclusion, air-con recharges are a welcomed opportunity whatever the time of year, if done correctly. To prevent problems, drivers should use the air con more, they should get the system recharged more often, and we should be telling our customers that too. Last but not least, as Martyn says: “No gas, no re-gas.” 20 AFTERMARKET MARCH 2021 TECHNICAL www.aftermarketonline.net COLD COMFORT Gareth is looking ahead a few months to Summer, when A/C will be a hot topic once more, although it is really an all-year opportunity BY Gareth Banks CAE AMIMI