Good process for charging residential AC w/R22?

[masraum]

Is this a valid process?

https://www.hunker.com/12002633/how-to-charge-a-home-ac-compressor-with-r-22

Step 1
Turn on the air-conditioning system. Turn the thermostat to its coolest setting.

Step 2
Remove the caps covering the outside AC unit's R-22 refrigerant valves. These are found on the pipes entering the outside unit. Some valve covers twist off by hand, and some require an adjustable wrench.

Step 3
Screw an R-22 manifold gauge's left-hand hose onto the valve on the large refrigerant pipe. Only charge an AC system with gauges designed for R-22, as stated on the left-hand gauge.

Step 4
Screw an R-22 manifold gauge's right-hand hose onto the valve on the small refrigerant pipe.

Step 5
Purge the air from the manifold's hoses. Open each manifold handle for one second. The air in the hoses will exit the manifold's middle hose.

Step 6
Screw the R-22 manifold gauge's middle hose onto a jug of R-22 refrigerant.

Step 7
Turn the R-22 jug upright, so its valve faces upward. Open the R-22 jug's valve. This keeps the liquid refrigerant away from the valve.

Step 8
Let the system's refrigerant pressures equalize. The needle on the left-hand gauge will stop falling, and the needle on the right-hand gauge will stop rising when the system has equalized. This can take from three to five minutes.

Step 9
Look at the psi reading on the left-hand gauge. If the gauge reads below 60 psi, then open the left-hand gauge's handle for 30 seconds. Allow the pressure to equalize. Repeat this until the psi reading reaches 60. Allow the system to run for five minutes.

Step 10
Place a thermometer on the large refrigerant pipe 6 inches from the service valve. Take the thermometer's reading, called super-heat, once it has stopped dropping.

Step 11
Find the refrigerant pressure that relates to the thermometer's reading. If the manifold's left-hand gauge has a temperature scale next to the psi scale, then use it. If not, then use a pressure/temperature chart -- called a P/T chart.

Step 12
Compare the super-heat reading to the gauge's psi reading. If the super-heat reading is more than 20 degrees above the P/T chart's reading, then add R-22 until the super-heating reading reaches the optimal range -- between 8- and 18-degree super-heat, depending on the environmental conditions. Many technicians charge the system until it has a 12-degree super-heat; about 70 psi at 85 F. If the super-heat reading is below 7 degrees, then the system usually has an overcharge, a stuck metering device or a dirty coil.

Step 13
Close the R-22 jug's valve. Then disconnect all of the hoses, and replace the service valve caps.

This one looks good.
https://static.wixstatic.com/media/bbdd6c_f5d551d652e147f2b41d583a03d6d185~mv2.jpg/v1/fill/w_1000,h_2385,al_c,q_90,usm_0.66_1.00_0.01/bbdd6c_f5d551d652e147f2b41d583a03d6d185~mv2.jpg

or this one (and they agree, so that's a plus, leaving this one as a link because the image is quite large)

Finding the P/T charts is easy and straight-forward with the Internet.

Sadly, with the current FUBARness of the board, I'm not sure that this post will get any action until the board is fixed.

[masraum]

Ding!

[mattdavis11]

Yes and no. I never hook up gauges with the compressor on. You can, but why? Bleed the lines with compressor not engaged. Crack the center hose from the manifold loose, open each side independently, close, then the charge hose line by opening tank valve, tighten charge hose at manifold.

Getting it dialed in right takes some time, today it is cooler than yesterday, delta, bla bla bla. No system is the same, vent temp and line temp measurements will help.

Let me know if you are uncomfortable with this, Steve. Nothing but a ride down I 10 to me.

[masraum]

Matt, thanks. Yes, today is a bit cooler. I probably won't charge until the weekend. I'm just too busy at work. It's definitely needing a charge. My return to register differential is only 14º. WHen this AC is charged up, it keeps the house very comfy. It's still doing a good job, but I don't feel like quite as good as it was (of course it has been much warmer).

I think I'll give it a shot once. If that doesn't go well, I'll let you know. Thanks again!

[T77911S]

your gauges have pressure/temp on them already.
if you have an orifice tube charge by super heat if you can get a line temp on the low side back to the comp. there may be a chart on the cover to your unit for charging.
if TXV valve use subcooling.

[masraum]

Originally Posted by T77911S

your gauges have pressure/temp on them already.

good to know.

if you have an orifice tube charge by super heat if you can get a line temp on the low side back to the comp. there may be a chart on the cover to your unit for charging.
if TXV valve use subcooling.

Why did this come across like Charlie Brown adults "wah waa, waaaa, wah waah waaa?"

Oh yeah, because I have no idea. It probably doesn't matter, but this is a 30 year old unit, built/installed 1991.

I'm a novice at HVAC, so I have no idea what you're saying, but if it's important to not blowing up my unit (that I'm just trying to limp along a little longer before we replace it), please let me know.