How long does the expansion valve (throttle tube) last?

Most cars now have air conditioning. We love the feeling of cool air on these hot summer days and we don't often think about what it takes to keep an air conditioner working properly, that is, until something…

Most cars now have air conditioning. We love the feeling of being cool on those hot summer days, and we don't often think about what it takes to keep our air conditioner working properly until something goes wrong. An expansion valve (throttle tube) is a component that is used in your car's air conditioning system. What it does is regulate the pressure of the A/C refrigerant as it enters your car's evaporator. It is in this tube that the liquid refrigerant is converted into a gas due to the pressure that converts it.

What can happen to this valve is that it can get stuck open or closed and sometimes get blocked. Once either of these happen, the air conditioner will not be able to work properly. While this is not a safety issue, it is definitely a comfort issue, especially in the middle of summer. There is no specific valve life, it is more of a wear situation. Obviously, the more you use your air conditioner, the faster it wears out.

Here are a few signs that could signal the end of your expansion valve's life.

• If your expansion valve is cold and frozen but the air conditioner isn't blowing cold air, there's a good chance the valve needs to be replaced. It is most likely that an excessive amount of refrigerant is being used, causing the core to freeze and air cannot pass through it.

• As a more basic symptom, it may be that cold air is blowing, but not cold enough. Again, this is a sign that the valve needs to be replaced or at least inspected.

• Keep in mind that air conditioning can help remove moisture from the air, which is important when you use defrost in your car. You won't want to go without it for long if you live in a humid climate.

The expansion valve (throttle tube) ensures that your air conditioner is working well and that the cool fresh air you crave is blowing out the vents. When it stops working, your air conditioner will also stop working. If you are experiencing any of the above symptoms and suspect that your expansion valve (throttle tube) needs to be replaced, have a diagnosis or have your expansion valve (throttle tube) replaced by a professional mechanic.