27 — Equipment for refilling air conditioners

Modern air conditioners consist of several important mechanisms that provide cooling or heating. An indispensable element of this system is the refrigerant. If there is a lack of it, the equipment works with overloads, which quickly leads to breakdowns of the air conditioner. To replenish the required supply of refrigerant, it is refilled.

In the article we will look at information about refilling a room air conditioner, what freons are used, how often it is necessary to refill the air conditioning system, and the work procedure.

Types of refrigerants for refilling air conditioners

In modern split systems, freon is used as a refrigerant - a gaseous substance that turns into a liquid state under the influence of a compressor. Improper installation of equipment, as well as various malfunctions of the device can cause freon leakage. In such cases, the air conditioner is refilled or refueled.

What types of refrigerants are used to charge split systems:

• R22 – can be used to partially and completely refuel the system;
• R410A is a modern version of the refrigerant, freon consists of 2 components, if there is a leak of 40% or more, a complete refill of the device is required;
• R-407C - contains three types of freon, is not used for refueling, only to completely fill the system.

Each type of freon has a certain cost. The safer the composition, the more expensive it is.

It is unacceptable to use the wrong brand of freon for the sake of saving money. On the housings of the outdoor unit, as well as in the technical data sheet of the device, there is a marking indicating the specific type of freon recommended for refilling the equipment.

Refilling window air conditioners

• Refilling window air conditioners

Window air conditioners stand out against the background of their numerous analogues.
They have a monoblock body format, compact dimensions and fairly high performance. It is also worth noting the affordable price tag, trouble-free use and long service life. But they also need refueling. Moreover, it should be carried out in strict accordance with the recommendations offered by the manufacturer. And remember. You should think about refueling your equipment at least once during the season.

Relevance of refueling

The following signs may indicate the need to refuel the system:

• Deterioration of operating parameters in cooling mode;
• Decrease in the overall efficiency of equipment operation;
• Icing of certain elements inside the freon circuit;
• Visual lack of refrigerant in the air conditioner.

In any of these situations, you should immediately contact specialists for help.

Note. To charge the system to the required level, you can use the maximum temperature difference of freon at the entrance to and exit from the system.

Aspects of refilling the air conditioner

The refueling process itself includes the alternate implementation of the following stages:

• Finding the cause of the leak and eliminating the existing problem;
• Refrigerant removal from the system due to depressurization of the circuit;
• Soldering the service port in the place of the drain branch;
• Evacuate the port for at least a quarter of an hour;
• The gas station itself. It can be carried out by weight, based on thermometer readings or using a pressure gauge;
• Turn on the monoblock and start the compressor. If there is no reaction, the cylinder is first disconnected and the gas is heated. The container does not close.

Refueling is carried out with the compressor running. In this case, turning over the gas cylinder is excluded. After refueling is completed, the operation of the system is checked for 40-60 minutes. Monitoring the temperature difference at various points in the circuit is mandatory. The optimal difference should be about 13 degrees. It is also worth checking the current consumed by the compressor.

At the final stage, the hose is disconnected and the service port is closed and sealed. At this point, refueling is considered complete.

Important! When refueling, special attention should be paid to the pressure inside the system. It should not exceed the operating parameters of the unit. Otherwise, certain problems may arise. The optimal pressure is considered to be 3.6-4.2 bar at a temperature within 20-22 degrees.

Where is freon located and how does it work in an air conditioner?

The indoor and outdoor units of the split system are connected to each other by copper tubes that form a refrigeration circuit within which freon circulates.

How does freon work in an air conditioner?

1. Low pressure refrigerant flows from the radiator to the compressor.
2. Under the influence of the compressor, the freon is compressed and subsequently heated to 75-80 degrees, after which it enters the condenser.
3. Under the influence of the evaporator, cooled by the air flow, the refrigerant cools and passes from a gaseous to a liquid state.
4. Freon passes from the condenser to the thermostatic valve. Passing through the capillaries, the gas pressure decreases, the freon cools, and part of it evaporates.
5. Next, it enters the radiator, blown by an air flow, where it is converted into gas, taking away heat, as a result of which the air temperature in the room decreases.

Freon pressure standard

The freon pressure level in air conditioners is ambiguous and depends on the ambient temperature, the brand of refrigerant and the operating mode of the equipment.

For example, when working in cold weather with an ambient temperature of +240, the standard operating pressure for suction of R410A freon is about 8 bar, and the operating discharge pressure is 20-25 bar.

Freon temperature

The temperature of freon gas at the exit from the evaporator is 15-200C. When compressed, it heats up to 80-900C. Then, when it enters the condenser, it cools down again and turns into a liquid state. At the outlet, the freon temperature is 10-150C higher than the outside air temperature.

How to charge the system

There are several fairly simple ways to cope with this task yourself.

• Initially, the cylinder containing the freon must be weighed.
• Having opened the gas outlet, it is refilled into the installation until the cylinder is empty to the desired value.

In order not to have to calculate the remaining amount of freon in the installation, you can not refuel at all, but refill the entire system again. To carry out this process, all the freon that remains in the air conditioner is released outside through a special valve. The new amount of freon in the air conditioner is determined using scales. The installation is filled only with the amount indicated on the innermost body of the system, the data that is always indicated by the manufacturer. This refueling is a fairly simple and safe process.

Recommendations from experts suggest that it will be much more effective to slightly underfill the required amount of refrigerant into the split system than to put an excess of it there. This is due to the chemical property of freon to pass from a liquid to a gaseous state. If there is too much refrigerant in the installation, it simply will not have time to transform from one state to another.

You can determine that there is not enough gaseous substance in the split system using a regular thermometer. True, this method is not suitable for inverter installations. So, bring a thermometer to the fan. And if its temperature is 5-8 degrees, which is usually indicated in the device’s passport, then this is an indicator that the air conditioner is operating in normal mode, with normal power, and the amount of refrigerant is quite normal.

When is it necessary to recharge the air conditioner?

Several signs indicate the need to refill/refill the air conditioner with freon.

What indicates a lack of refrigerant in the system:

• formation of frost and ice on fittings and pipe connections;
• frost appeared on the outdoor unit;
• The air conditioner began to cool the air poorly.

Refilling with freon is also necessary after dismantling and reinstalling equipment, as well as after repair work, which could result in a refrigerant leak.

Is a new air conditioner charged during installation?

Household air conditioners are sold already charged with refrigerant at the factory, so after installing new equipment there is no need for this. If the installation is carried out by technicians from a service center, they can check the pressure in the system using special equipment, which will also determine whether there is enough freon in the system for normal operation of the climate control equipment.

Air conditioning for a private house, cottage: types, selection, installation

Kit for refilling air conditioners SM-99

A kit for refilling air conditioners is an assembled set of equipment designed for diagnostics and refilling with freon (refrigerant) of car air conditioners, household and industrial air conditioners, as well as various climate systems. The device is small-sized and lightweight, and the plastic case allows you to conveniently transport the equipment when visiting the client.

The photographs show kits for refilling air conditioners SM-99, SM-99A, SM-100, SM-101.

The SM-99 and SM-99A kits were specially created for servicing household air conditioners and refrigerators; the kits contain adapters for R22/R410 gas. The main difference in the kits is the dimensions of the portable case and the presence of scales.

The SM-100 and SM-101 kits are designed for servicing automobile air conditioners. The main difference in the kits is the dimensions of the portable case and the presence of scales.

Applicability:

R22, R134a, R410a, R407C / R22, R134A, R404A, R407C.

A fully equipped technical product ready for use.

Functions:

• Diagnosing the system - searching for leaks, determining the amount of freon in the system by pressure;
• Evacuation of the system;
• Filling the system with oil (for car air conditioners);
• Refilling the system with freon by pressure;
• Fully charging the system with freon.

Specifications:

• Productivity - 51 l/min. It is possible to install more high-performance vacuum pumps 70, 100, 170, 226 l/min;
• Limit residual pressure - 2 Pa / 0.00002 bar / 15 microns;
• Overall dimensions - depending on the version;
• Weight - from 10 to 15 kg, depending on the design.

Warranty - 1 year.

Options

How to refill your air conditioner correctly

Refilling the air conditioner occurs in stages, following certain rules. This work is performed by specialists from the service center.

How to refill a split system:

1. Evacuation removes all air from the system.
2. The approximate volume of freon that needs to be pumped is determined. A special device is used for this.
3. A refrigerant cylinder is connected to the device and charging begins, controlled by a pressure gauge.

How much freon will be needed

The air conditioner data sheet contains information about what brand of freon is suitable for filling the circuit, what the pressure should be and how much refrigerant needs to be pumped into the system before it is fully charged.

If equipment is being refueled, technicians determine the amount of missing freon in the system using special instruments.

The approximate amount of freon in a split system is 500-750 g (in “sevens” and “nines”).

Filling an air conditioner with freon yourself is very difficult and almost impossible. This requires special equipment, relevant experience and knowledge. It is better to entrust such work to professionals from the service center.

Cost of refilling an air conditioner with freon

There is no dependence of the price of refilling the air conditioner on the method used. The amount is calculated relative to the power of the device.

But how much does refilling freon cost on average? A device with a cooling capacity of 2.5 kW will require about 3,500 rubles to replenish the refrigerant in its entire volume. For each subsequent standard size, 500-700 rubles are added. Thus, the price of refilling a DAIKIN split system with a power of 10 kW with freon will cost its owner 7000-8000 rubles.

To fully understand the process, you can watch a video that shows how to fill an air conditioner with freon using a pressure gauge station and scales: