R22 refill on air conditioning system / Refrigerant system gas recharge

Charging the gas onto air-conditioners or refrigerator is another service that we offer to all public. This is a very important factor to keep your ventilation system maintained properly if the units run out of gas it won’t be functioning as good as it should be so if you start to see any sign of your unit not functioning properly you’d better get in touch with a company like us who can help save you from having headache as you don’t want to end up having a breakdown especially during summer months when the temperature can get very high.

Procedures for Recharging Air Conditioning Systems with Refrigerant

Refrigerant charging might be the least understood practice in the air conditioning industry next to setting airflow. Although there are several methods, typically there is only one correct method for the type of unit you are working on. Information contained here is for formally trained EPA Section 608 certified technicians.

Charging a Home AC Compressor With R-22

Most homes with an air conditioning system manufactured before January 1, 2010 use R-22 as the refrigerant. The AC compressor circulates the refrigerant through the system's pipes, metering devices and coils. AC systems with a low R-22 charge do not perform at peak efficiency. In a clean and sealed system, an R-22 charge of less than 58 psi forms ice on the evaporator coil -- the inside coil. If the AC system has clean, leak-free coils, a clean filter and both fans operating at the correct speed, then charging an AC with the correct amount of refrigerant maintains peak performance.

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.