Carrier fk4dnf005- what are my options for 7 years old unit if leaks in Coil...to replace or got for new system ?

SOURCE: Coil leaking freon on the inside unit. Estimate is $2,100!

If indeed your evaporator (indoor) coil is leaking, the best option IS replace it (it may not even BE repairable). If you live in the USA and your furnace is getting old, a new ultra high efficient SYSTEM that qualifies for the tax credit would probably be a better option (Obama will pay 30%).

SOURCE: How to replace a evap coil on a carrier package

Hi, the coil will need to be taken from the top, or by removing a side panel. Its located on the return side. The freon will need to be recovered unless the unit is dry. You can use a close quarter tubing cutter to cut it as close to the coil inlet at metering device and outlet. The new coil will need to be silver soldered in place using a hot enough torch set-up to melt silver solder, or sil-phos sticks that will need to be bought at a air conditioning parts house. It melts and starts to flow at around 1,385 degrees F. You will need to pressurize unit to check for leaks using dry nitrogen. Once you know you have no leaks, let the nitrogen out and put a vac-pump on system for about 45 min along with a manifold set of service gauges to pull the unit down to a minimum of 28 H.G.'s. After that, its time to recharge the unit. The best way is to look on the data plate for the units amount, purge your hoses and weigh in your charge. This way you know you have the right amount in the unit. A tip for you, when brazing in the new coil, wrap wet rags around expansion valve to prevent it from melting the internal parts. You really should have some training on doing this. To buy freon for it, you will need to show that you are a C-20 contractor and your certification card. Its not a easy task, and you must have the right equipment and hand tools to do this. This is the only way to replace any coil, as they are under high pressure when charged. I wish you the best of luck. Please rate me on this post, and you can contact me for help by my user name below.
Sincerely,
Shastalaker7
A/C, Heating, & Refrigeration Contractor