Air conditioner replacement--new size required?

I can find no A27 fault code for this unit, what is it doing? You can call carrier and ask for the definition, I think they will give it to you, just have the specific model number in hand when you contact them.

I can't find a filter to fit my Carrier air conditioner it needs 16 1/2x21 5/8x1 where can I find this can you please help, thank you

The number you are referring to as your 'model number' is a number I don't recognize; maybe it's the SN or something - I don't know.
But that other number - "38CKC042" -------'is' --- your model number and the size of your AC is 42,000 Btu or 3.5 tons.

It all depends which coil you are speaking of, Evaporator or condenser if you are lucky to find a used match which is highly unlikely. newer units have has their seer rating changed substansually causing both coils to be replced at the same time and by the time that is done a new lineset is required to elliminate cross contamination so its not good news depending on required tonage 3000 to 5000 dollars installed sorry wish it was better news

2 ton

is it horizontal or vertical 2 different sizes

is this unit real old ? it does not come up in my book . the btu is 30000 that is the same as 2.5 ton it may be 6,7 or 8 seer i dont think its a 10 seer because the 10 seer units are listed and yours is not . if this sounds wrong please look up the mod # again and post the ser # too ......... Please if this answer helped , please rate this 3 or 4 stars . and keep me in the paid answer department . A 1 or 2 may knock me down into the unpaid ranks. Thanks Cactus Bob .

What part of the country?
How many square feet in the house?
Insulation?
Single pane glass?
Many factors should be considered by a professional.
However if the old unit worked OK, a new 80% 70,000 unit will most likeley replace a 24 year old 60-70% 75,000 unit.

This unit was manufactured 1/8/00 and is a 4 1/2 system

Hi, most of the time generic parts are used to replace bad ones. The voltages and microfarads or UF is what's important on the capacitors and the amperage and control voltage on the contactor. Your unit will not run better with new parts and I suggest your time and money be used to clean and check your unit instead of "tuning it up" with new parts. If the capacitors are swelled or leaking oil they need replaced. If the contacts are pitted or burned, they need replaced. The condensing unit will need cleaned from the inside out. Remove the fan assembly and spray from the inside out on each of the condensing coils to remove the debris stuck inside the fins. If there are oil ports on your fan motor, add about 4 drops of oil into both of them. The same on your inside fan motor. If it has a fan belt inside check it to make sure it isn't worn too badly. Adjust it if needed to give about 3 inches of play. Too tight will make your bearings go bad. Oil your bearings if the fan has then and they have oil ports. Check the evaporator inside to see if it has a blanket of fuzz on the side where the air enters it. It can be removed with a credit card when wet. Scrape along with the fins if it needs cleaned. With the unit running and the inside of the house fairly comfortable the large refrigerant line outside should sweat all the way up to the compressor but the compressor should remain fairly dry. If it does, you have a good refrigerant charge. With this cleaning and oiling your unit should work more efficiently and be ready for another year. NOTE: The heating/air-conditioning companies usually run a special on seasonal checkups. If you have one come out, Have them do all the above plus get your furnace cleaned and ready. If you want more information on the furnace, please let me know what kind it is and I will try to help. If this solution does not rate at least (ALMOST THERE) Please do not rate. Thank You. kstfas