Bellingham Auto Repair

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Do you have a cool car?

There are similarities between your cars air conditioner and it’s engine cooling system. Each has heat exchangers in front of the vehicle and another similar device inside the dash.

Back behind all those buttons, dials, trim pieces, motors and sensors we call the dash board lives a plastic box called a heater box. Inside that box we find a heater core and an evaporator. One puts heat into your cars interior and the other takes heat out. They work together to keep the cabin air just right. Like Little Red Riding Hoods portage; “not to hot, not to cold but just right.” All these parts taken together are referred to as the climate control because that’s what your air conditioner and heater do. They control the climate. Not just the temperature but yes the climate.

Most modern climate control systems include a computer, sensors, a fan with a cabin dust or pollen filter. Some sophisticated four zone systems include a sun sensor which will help the climate control maintain the set temperature. If the driver sets his temperature to a cool setting but the sun is shining directly on him, some climate control systems will take that into account and adjust the temperature accordingly.

If there is a failure of a sensor or one of the numerous little plastic doors or motors your car’s climate control may tell the automotive technician with a diagnostic fault code which will help him accurately and quickly find your heater problem.

In the winter when your start your car the engine begins making heat. This heat can be channeled as hot coolant/antifreeze into the heater core. The climate control fan will then move air through a cabin air filter across the heater core to the area of your choice. You can use the buttons on the dash to direct the heat to your feet, out the center vents or direct it to the windshield with the Defrost button.

The defrost setting is, as the name would imply, for defrosting or defogging the windshield.  The defrost setting will direct warm air onto the inside of the windshield and may for a moment cause some fogging because of the temperature difference between the outside of the windshield and the inside of the windshield . But the defrost setting also turns on your air conditioner. Yes even in the dead of winter when it is freezing outside and you want heat, the defrost turns the air conditioner on to de-humidity the cabin air and help clear the wind screen with dry warm air. This is why the modern car “heater” really is a climate control.

So the air conditioner is not just for putting cold air into the cabin in hot summer days. As a matter of fact the best air conditioner in the world will never put cold air into the car. An air conditioner can only take heat out of the car but never put cold air in. Why? Physics. The heater can put heat in but the air conditioner can only take heat out.

Much in the same way as the radiator helps remove heat from the engine so it doesn’t burn up, the air-conditioner removes heat from the passenger compartment so you don’t roast on hot summer days. By using a special refrigerant similar to the “Freon” which your refrigerator operates with the refrigerant (R12, R134 and now R123Yf). In the same way as your propane grill tank can get frosty, the air conditioner by allowing a compressed gas to expand rapidly collects heat and removes it.

Air conditioners like your engine cooling system need occasional maintenance. In the same way as you change the oil and filter in your engine or service your transmission, your engines cooling system needs it’s antifreeze/coolant mix replaced to help maintain the lowest lifetime operating costs of your vehicle. And just as you need to fill your tires with air even if there is no “leak” you also need to service your cars air conditioner. When you bring your car in for an air conditioning service your trained mechanic will recover the Freon in an environmentally responsible way. Then he will place the system under a vacuum to remove damaging moisture before charging you’re A/C with the proper refrigerant.

Master Auto Tech would like to help you take good care of your vehicle by offering a $40 discount when you service both your engines cooling system and your vehicles A/C at the same time. 

Call Today to reserve a time to invest in a cool car. 
Call 360 733-3043 
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