"No Need for an AC you said... Waste of Money you said.... We will get Used to it, you said... Blah, Blah, Blah..."

The Indian summer's here, with the mercury rising faster than a Ferrari's rpm. Ritujoy Chakraborty and Vivek Bhat give the complete low-down on car air-conditioners for the beating the heat.

Driving in India without an air-conditioner (AC) during the summer months may be rewarding for those on a diet, but for everyone else an AC is today a necessity rather than a luxury. Whether it’s the heat or the lethal pollution that bothers you most, the AC is an integral part of the driving survival kit in the sub-continent.

Admit it, all you motorheads - given the choice between a non-AC Ferrari and an AC Lancer on a Delhi road in the middle of May, there isn’t much debate. If your car doesn’t have an AC, then either you’re Superman or you’ve been living in the Stone Age. About time you bought one.
Our guide shows you how to get the most from your AC if you already have one, and helps you choose the best if your car didn’t come fitted with AC.

GETTING YOUR AC IN TOP SHAPE

Climate control system in a Merc S-Class. Doesn't get any better than this.

Many drivers may be surprised to hear this, but an AC needs maintenance. Says Nitin Gandhi of Bharat Car Airconditioning, “It’s sad that car owners have a ‘chalta hai’ attitude when it comes to looking after their ACs. In fact, only after there is complete loss of refrigerant or a choked compressor does the average owner go running to the AC dealer. If they were to keep a watch-out for a drop in cooling, and have it checked out, such disasters wouldn’t arise.”

Here are the key points to remember about servicing your AC before you go heat-busting this summer.Check the gas level The refrigerant gas in your AC (known as Freon) has a habit of escaping slowly. For this reason, it is very important to have the Freon level checked each season before you start making heavy demands on your AC. It’s also necessary to have the compressor oil level checked since that is the best indicator of an unnatural gas leakage. Also, evaporators (cooling coils) have a habit of getting corroded. Check them too.

Clean the system thoroughly Dust settles on your car when it is parked and can get into the AC blower motor’s intake snorkel. Worse still, if you park under a tree then fallen leaves can work their way past the slats on the bonnet and block the passage of air to the blower, thus reducing the efficiency of the system. Sometimes, such debris gets lodged on the condenser too. If insufficient air is passing through the condenser’s fins as a result, cooling will again be affected. Have these checked.

HOW TO MAKE MOST EFFICIENT USE OF AIR-CONDITIONING
1. After parking in the sun, vent the car for a minute or so before using the AC. 2. Keep the sunroof and windows closed. 3. Keep the blower fan speed steady. 4. Use the recirculation function for faster cooling and to keep unwanted     odours out of the car. 5. Use the multi-flow system to keep the windowscreen clear.

MAKING THE MOST OF YOUR AC

No, it’s not as simple as closing the windows and switching on the blower at full blast. You will eventually get cooled that way, but it could cost you more than a browful of sweat. For top tips on the best way to use your AC, we asked Shripad Ghurye of Simran Sales (Subros dealer).

Moving off The interior is always hot when the car has been standing for a while. The best way to get the temperature down quickly is to keep the circulation switch on ‘fresh’, or roll down the windows a little, which lets the hot air escape. Then roll up the windows, turn the circulation switch to recirculate, and pop the AC switch. This way the hot air is evacuated faster and the cabin is cooled quickly.

How many on board? With just two of you in the car, it’s best to have the AC set to blow air at the face and feet. If there are more than two people in the car, the full airflow should be directed through the dashboard grille, so that the rear passengers also get a draught of cool air.

Driving slowly The faster the engine runs, the more effectively the AC operates. In a traffic jam, or up a long incline, use a lower gear than usual, thus maintaining a higher engine rpm. This will prevent the engine from overheating and provide better cooling. More importantly, it will prevent the engine from stalling, which is the last thing you would want to happen in the summer heat.

Driving fast With the temperature setting at the coldest position, driving at high speed for hours may cause frost build-up in the evaporator. This is also called ‘icing’. When this happens, the blower speed drops and the temperature inside the cabin begins to rise. To avoid this, adjust the temperature to a medium cold setting, which allows the thermostat to cut off the compressor before icing takes place.

Parking Did you know at the peak of summer, the closed cabin of a car parked in the sun can exceed 55deg C? Remember walking into such a car, touching the steering wheel and screaming out the choicest expletives? To avoid this, always try to park in a shaded place. If you must park under the blazing sun, make it a point to leave the windows down an inch to avoid the cabin becoming a furnace.

RETROFITTING AN AC
While most cars nowadays come with a factory-fitted AC, there are still a few models that do not. Many owners of these cars soon opt for an aftermarket AC system. Most cars can handle a retrofitted AC - but you need to follow these guidelines to avoid wasting money on a system that’s wrong for your car.

• lConsult your car dealer for the details of the ideal brand and size of AC for your vehicle. Even if you bought the car used, your local dealer for that make is still the best person to ask. This is because certain brands are approved by certain manufacturers - for example, Nippon-Denso compressors and Subros condensers for Maruti cars.

• Once you have an idea of the brand and size that would be right for your car, seek out authorised fitters/dealers for the job and the best quote. (There are also many reputable non-authorised dealers/fitters who have been in the business for ages and have acquired a high level of expertise.) Ask each fitter to give you a brief outline of how they propose to carry out the job, which should ensure that the fitter quoting the lowest price is not overlooking anything.For example, in earlier-generation Maruti 800s, the 80-watt blower fan needs to be replaced by a 120-watt fan for proper cooling. This costs around Rs 2000. Such expenses should not be dumped on you as hidden costs after the deal has been struck.

• Under no circumstances should you go for shady deals at unusually low prices. It’s quite possible that a used AC is being peddled off as new

AC TROUBLESHOOTING
Normally, there are three signs that are a giveaway that something is wrong with your car’s AC system.

• The cabin is not getting sufficiently cool.

• Acceleration is noticeably slower with the AC on.

• Noises from in and around the compressor.

Frankly, there isn’t much that you can do in terms of diagnosis and repair. Rather, get the car to the specialist AC serviceman as soon as you can.

WHEN SUMMER’S OVER
Just as you would wrap up your car before leaving on a vacation, your AC needs a bit of help to remain in top condition until the next summer. Here are a few tips:

• Do not discharge refrigerant gas.
• Do not dismantle the AC in any way.
• If the water thermostat has been removed during the summer, you need to reinstall it to prevent the radiator water from getting excessively cooled.
  
• Finally, the biggest secret - operate the AC regularly even during the ‘off’ season! This circulates gas and oil through every part of the machinery, thus keeping it ready to spring into action when summer is back.

While new-generation cars have no problems coping with regular ACs, older vehicles like the first and second-generation Maruti 800, the Maruti 1000 or the early Unos are often at a loss at the height of summer. Owners of these vehicles have had varied complaints, ranging from poor insulation, to non-existent pulling power up an incline with the AC on, to leakages springing out from every nook and corner. Thankfully, newer versions of all these vehicles have for the most part had these problems sorted out. However, if you happen to own an old vehicle, whichever make it may be, it’s always a good idea to keep a watch over the engine temperature gauge to prevent overheating.

This is not a bad idea on new cars as well, since where the Indian summer is concerned, as the Brits say,
it’s bloody hot!

TYPES OF AC
Essentially, there are five types of AC:
Cooler with simple blower
The basic ‘cool’ AC with unidirectional blower unit, as fitted in the Premier Padminis.

Cooler with multi-flow blower
Again only cooling, but with multi-directional vents for all-round cooling, as found in the Maruti 800.

HVAC (Heating Ventilation Air Conditioning) with simple blower
This has both cooling and heating, but only a unidirectional blower unit. The Mahindra Bolero is an example.

HVAC with multi-flow blower
Cooling and heating with multi-directional vents. Some cars, such as the Honda City, have dedicated ducts for the rear passengers.

Climate control (also called automatic AC)
This hi-tech system is designed to maintain cabin air temperature at the desired pre-set level by using various sensors to detect the cabin air temperature, ambient air temperature, quantity of solar radiation and the engine’s water temperature.

The sensors pass on the information to a microcomputer, which determines the temperature of the air it needs to blow out, thereby controlling the refrigeration cycle system. This is as good as it gets, as you would expect in a car like the Mercedes S-class.

TIPS TO BE COOL

1. Always make sure the refrigerant is topped up. Check the bubbles in the receiver-drier sightglass.
2. At every service, get the condenser blown with compressed air to keep it clear of dust and debris.
3. Fix a light shade film on the door glass to allow light in and cut down heat.
4. When starting off, allow the hot air to exit by opening the window, before switching on the AC.
5. When parking, keep the windows open an inch for the air to circulate.