how do I charge a central A/C unit.?

Question

I have no experience at this, but know I can do it with the proper
instructions.

Answer 1

You should call a professional for this job. You have to capture any freon in the system to keep it from being released into the atmosphere. Charging a system is something that rarely needs to be done unless you have a leak, and very expensive equipment is needed to perfom this task properly.

Answer 2

THE FEDERAL LAW IS THAT YOU CANNOT BUY THE REFRIGERANT UNTIL YOU ARE CERTIFIED. STATE LAWS VARY BUT IN AT LEAST SOME STATES YOU MUST HAVE A STATE ISSUED A/C LICENSE TO GET REFRIGERANT. LETS ASSUME YOU HAVE SOME YOU FOUND IN YOUR GARAGE CAUSE IT IS ILLEGAL FOR SOMEONE TO SELL IT TO A NON-CERTIFIED PERSON. IF YOU DETERMINE THAT THE UNIT IS LOW ON CHARGE THEN YOU ALREADY HAVE GAUGES. OTHERWISE YOU CAN'T BE SURE WHAT IS WRONG. SO NOW YOU MUST HAVE THE GAUGES AND REFRIGERANT. NEXT YOU NEED THE INSTALLATION INSTRUCTIONS OR THE CHARGING CHART. HOPEFULLY THE CHART IS PASTED ON THE INSIDE OF THE UNIT. THEN YOU SIMPLY TAKE ALL THE TEMPERATURES AND PRESSURIZE THE INLET WITH REFRIGERANT VIA THE SUCTION SIDE VALVE. CERTAIN REFRIGERANTS REQUIRE THAT THEY BE INJECTED IN THE LIQUID STATE AND OTHERS ARE INJECTED IN THE VAPOR STATE. NEXT YOU WILL FIND THAT THE LOW SIDE PRESSURE IS TOO LOW AND THE HIGH SIDE PRESSURE IS JUST RIGHT AS COMPARED TO THE CHART. SO YOU FINALLY GIVE UP AND CALL THE SERVICEMAN. HE COMES AND LOOKS THINGS OVER AND GOES INSIDE-REMOVE THE PLUGGED UP AIR FILTER AND COMES BACK OUT, ADJUST THE REFRIGERANT BACK TO THE PROPER LEVEL AND HANDS YOU THE BILL. --OR SOMETHING LIKE THAT. THERE ARE TOO MANY THINGS TO THINK ABOUT AND IT IS TOO EASY TO MAKE A MISTAKE.

Answer 3

I think you can do it too, assuming you have the tools and freon, which you can get. You'll need gages with hoses that attach to the tank of freon and attach to the AC unit. This equipment ain't cheep, but will pay for itself over time. When you pick up the gages and freon from a supplier, you can get a chart that tells you how much pressure/temperature is required. Your owners manual for your unit will tell you where to connect the hose, but there is only one connection that will receive it. You will need illustrations on how to connect which color coded hose from one gage to the unit and another to the tank of freon as there are four hoses and only two are utilized, and two gages and only one certain gage used for the charging process. I wouldn't even try to explain it in detail as it is unsafe. But you should still do it because I do most everything myself. I worked for an AC man for five years. You should be able to pick up an instructional manual on this subject from Home Depot or Lowe's.
I hope this points you in the right direction. Be Safe

Answer 4

werehunter is right, you can do it yourself, but you need the guages. Without them you are going to under or over charge the unit.

Having said that, are you sure that you are low on freon? Most times it is a matter of dirty coils. You need to clean the inside part of the unit (the air handler) and the outside at least once a year. You can do this with water. Please be sure to turn the unit off before you start.

Answer 5

You don't. This is one of those times where you just call a pro. You will not have to charge an HVAC unit often, and the certifications and costs and equipment will not beat the cost of hiring a pro.

Answer 6

you have to be licensed to collect the old refrigerant and recharge the system. call a pro.

Answer 7

you call an a/c mechanic to your house and let them do it