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in the Phoenix Metropolitan Area

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in the Phoenix Metropolitan Area


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Cool Touch Air Conditioning and Heating Blog

The Line Set for Your AC: Another Reason to Only Trust Pros!


You never want to run into air conditioning troubles during an Arizona summer. It’s one of the worst problems that can affect a home in the state, since temperatures above 100°F are commonplace through the middle of the year. We take our job as air conditioning technicians seriously because we know how important it is to the health and happiness of our customers.

We’re often called on to help people with air conditioning replacement in Sun City, AZ when their old systems start to fail. Often, we discover that the contractor who installed the first system took shortcuts that caused problems. We want to bring your attention to one of these shortcuts because it helps explain why hiring professionals from the start is so vital.

Introducing the Line Set

You probably don’t know what the line set for your air conditioner is. If you have a standard split system air conditioner, i.e. a system with an outdoor and indoor cabinet, the line set is the pair of copper pipes that connect the two units so refrigerant flows between them. Circulating refrigerant is how an air conditioner moves heat from inside a house and releases it to the outside.

The line set consists of two different copper pipes. The smaller pipe is the liquid line, which transports the cooled-down liquid refrigerant from the condenser to the indoor unit. The large pipe is the suction line, which carries the warm refrigerant from the indoor unit out to the condenser and eventually to the compressor.

There is no standard size and length for these copper lines. The pipe size depends on the type of air conditioner and its efficiency. Pipe length is different for each house because of how the condenser and the indoor unit are positioned. When installing or replacing an air conditioner, professionals must know the right type of size of copper pipes to use for the line set.

Replacing the Line Set

When you have a new air conditioning system installed, your technicians must make a decision about whether to replace the line set as well. It isn’t always necessary to put in a new set: copper lasts for many years, and if the new system is similar to the old one and from the same manufacturer, the current line set can remain in place. Our technicians will always check to see if the line set is the correct match for a new system.

On the other hand, if the line set is easy to access, technicians will often replace it to ensure the new system has the best possible start and minimal danger of leaking in the future. The line set must be replaced if the new air conditioner is an R-410A unit replacing an out-of-date R-22 unit, or if the current line set doesn’t match the specifications of the new system (either because of efficiency or manufacturer differences). If the line is damaged or has kinks, it should also be replaced.

Unfortunately, amateurs often ignore the line set completely and leave it in place no matter what. Maybe they’ll get lucky—but this isn’t something you want to bank on! Always look to professionals when you need a new air conditioning system for your house.

Cool Touch Air Conditioning and Heating serves the Phoenix Metropolitan area with the best in keeping cool. Call us for the AC help you need, any time of the day or night.

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