How do you recharge ac with freon?

Answer 1

= = = Having problem with your A/C unit? This is how you fix it… = It's very important to remember though that a licensed person is the only individual permitted to perform this kind of job, especially when dealing with AC gas. If you are here looking for helpful tips, it's obvious you are not licensed. You can very well go for it, and with the right attitude, although still costly, more likely you will succeed; but always keep in mind that you are on your own. First of all, let's see which one of the following situations best fit your case and let us concentrate on that one. Each problem got totally different solution. 1st Unit not blowing enough heat/cold: 2nd Unit blowing heat/cold but very low air pressure 3rd Unit not turning on at all 1st: Unit not blowing enough heat/cold: For the purpose of this documentary we will focus on this situation as it is the most common and complex. There is a good chance you are having problem with Freon gas, and therefore the presence of a leak. Troubleshooting… First, kill the power to the entire unit, including condenser. Go to the outside or roof, wherever your condenser is located. For now, just bring with you a set of socket wrenches, a set of screwdrivers and an electrical meter; make sure unit is dead (no power). Remove fan and cover on condenser. Give your unit a visual check. Look for oil residue on any solder joints or fittings. A spot of oil is a definite leak. Keep looking until you find it, and when you do, time to work! Let's find out how much gas the system got left, if any. (Outside of the electrical panel cover of the condenser you will find the type of Freon gas for your unit and amount required in Lbs & Ounces). By copper lines, outside of unit, look for two valves, one for the low side or cold (insulated) and one for the high side or hot (not insulated). Open valve (release) to see if there is any pressure inside the unit. No pressure means no gas and unit needs recharge, otherwise it just needs adding. But considering the presence of a leak, I recommend vacuuming the system for either case, but recycle any gas in the system into an empty gas-recycling tank. Remember, if you got a leak and pretend to fix it just by adding, think again. Whatever you do though, never let this gas out into the atmosphere. To recycle gas, just attach the empty tank into the outlet of the vacuum pump and follow instructions. To learn more about vacuum pump and gas recycling, see details ahead on how to vacuum the unit. The unit manual also has detailed instructions on how to use your vacuum pump to vacuum your AC unit. * Pressurize the unit using nitrogen: Assuming the unit is completely empty, with a Tire Valve Tool ($2 available at any auto parts store), remove valve stem from the low-pressure side valve. # I recommend attaching a pressure gage into the nitrogen tank to be able to control pressure. (If you can't find the right size fitting to connect the pressure gage outlet to the unit being served, get yourself a reducer close in size to the valve size, and from the auto part store buy a hose of that size. Using clamps to securely tighten the hose, connect the gas tank/pressure gage outlet to the low-pressure side valve of the unit.)

# Get you a spray bottle with dish soap and water. After pressurizing the unit, spray all over copper lines, fittings and coil condenser, but concentrate in areas where you see oil residue. With the pressure already inside the unit, keep spraying soap around the lines, if there is any leak, it will start bubbling through the pinhole, and that way you will locate the leak (increase pressure if needed, 100 psi should be plenty). After marking any pinhole you discover, remove valve stem to release pressure. Now get ready to do some soldering.

# Get you a soldering torch, an acetylene bottle and a 5% silver stick or 15% for better quality. Solder over any pinhole you found. Make sure you feel good about the job been done as you don't want go back and forth. After done soldering, pressurize the unit again and repeat this process until the unit is leak free.

# Using the Tire Valve Tool, put valve stem back, and now get ready for vacuuming.

* Vacuuming the unit: The unit most be vacuumed for two main reasons a) to have a negative pressure in the system for charging later and b) to remove the moisture inside the unit. To vacuum the unit, do as follow: # Get you a vacuum pump for A/C; RG5000 does a pretty good job. You are also going to need a pressure gage. Take the pressure gage and attach the blue hose to the low side (insulate), attach the red hose to the high side (not insulated), and attach the middle yellow hose to the intake side of your RG5000.

# Make sure you have all fittings snuggly tight and all valves open from both the pressure gage lines as well as intake and out of the vacuum pump. The black middle knob of vacuum pump unit must be on Recover position.

# Leave vacuum pump running for about 1 hour. At that point the system should have a negative pressure of -20 to -25 PSI and moisture out of the system. Turn off vacuum pump while closing valve from the yellow hose attached to it, then close valve from the red hose attached to the unit being served, leaving the blue side of the gage open. Remove the yellow hose from the vacuum pump unit. Gage should stay reading the negative pressure inside the system. Leave all as it is, but make sure you don't loose pressure. Now get ready to charge the unit.

* Charging unit: A few things to consider before you begin. First, you are going to need a tank with the same type of Freon required (for most home units R22). Make sure you got enough gas in the tank to fill up the system. If it's cold outside, go to cold weather condition explained at the end of this documentary. You are also going to need a weight scale for AC gas. If you need help on how to charge the system accurately, see example on how to calculate gas weight at the end of this documentary. Now follow these instructions to charge your unit: # Assuming that 1st only the blue hose valve is open (low), and 2nd gage is still reading same negative pressure inside the unit, attach the yellow hose to the Freon gas tank. Be aware that we are only going to use the low-pressure side to charge the unit. Place your Freon tank on the weight scale. Open valve from yellow hose, and slowly open the tank valve as you begin to charge the system.

# Once the weight scale reaches the value you calculated previously, your unit has been fully charged. Now close your tank valve and remove pressure gage from both sides of the unit, then remove gage from the tank.

# Put fan and unit cover back. Turning on unit for testing.

* How to charge A/C Unit in cold weather: if outside temperature (OT) is cold and this procedure is not followed thru, more likely you won't be able to charge your unit as you will have a hard time to get the gas out of the tank. To charge in cold weather, do as follow: # Leave gas tank inside hot water, like hot tub, for 30 minutes. Make sure valve is capped.

# Find a bucket big enough, to fit in the gas tank. With tank inside, fill it up with hot water. Make sure container is not too big or heavy, as you will need to weight the whole thing later on. Most weight scale for AC gas can only reach up to 60 Lbs.

# With someone's help, bring the whole thing to the unit being served.

# Start charging the system.

* Example on how to calculate gas weight before charging A/C unit. Let's say your gas tank weights 16 Lbs 2 Ounces, and according to manufacturer recommendations, to fill up the system you will need 5.25 Lbs. Since 0.25 is the same as ¼ out of 1, and 1 Lb equal to 16 Ounces, then 0.25 Lb is equivalent to 4 Ounces; therefore we can say 5.25 Lbs is same as 5 Lbs 4 Ounces. Lets subtract 5 Lbs 4 ounces from 16 Lbs 2 Ounces. Notice you can't subtract 4 Ounces out of 2 Ounces, so we convert 16 Lbs 2 Ounces into 15 Lbs 18 Ounces, and now we are ready to do our math. 15 Lbs 18 Ounces (previous tank weight) 5 Lbs 4 Ounces (amount being charged) 10 Lbs 14 Ounces (tank weight after charge) Once the weight scale reaches 10 Lbs 14 Ounces the system is fully charged (keep in mind that overcharging the system may damage the unit) Pending: 2nd Unit blowing heat/cold but very low air pressure 3rd Unit not coming on at all