After installation or repair of a household split-system, the working circuit is filled with refrigerant - a special substance that evaporates at low temperatures. According to the price lists published on the Internet, the price of this service starts from 2000 rubles (35 cu). An alternative is to save and solve the problem yourself. We suggest considering 3 questions: when it becomes necessary to refuel an air conditioner with freon, how much does it cost to rent equipment and how to do it yourself.
How often to refill a home cooler
Freon is downloaded to the split system in three cases:
- during installation or reinstallation to a new place;
- after repair, involving the shutdown of freon highways;
- as a result of refrigerant leakage from the circuit.
For reference. Mobile and window air conditioners, executed in the form of a monoblock, practically do not need additional filling of freon. Short tubes mounted at the factory are located inside the casing and are not accessible to “crooked” installers. Another thing is a car cooler that undergoes vibration and much more often loses refrigerant.
In fact, after installing a new air conditioner, there is no need to fill in the freon - the manufacturer pumps gas into the outdoor unit. Competent craftsmen do the same - when repairing or dismantling a split, the freon is pumped to the heat exchanger of the external module. The first two cases involve the loss of substance due to unsuccessful actions.
The following signs indicate an insufficient amount of freon in the system of the climate unit:
- cooling efficiency decreases - the fan of the indoor unit drives warm air;
- the compressor runs non-stop at full load;
- the inverter air conditioner goes into error and often turns off (the display shows a fault code);
- the service port located on the outdoor unit, where the liquid line enters, is covered with ice;
- under the influence of freon pressure, an oil appeared on the leaky compound;
- freezing of the evaporator of the indoor unit.
Note. The service ports of the split system are located under the cover on the side wall of the outdoor unit. 2 highways are connected to them, where freon circulates in a liquid and gaseous state. The diameter of the liquid tube is smaller than the gas.
On the video and websites of companies involved in the installation of refrigeration machines, there is a recommendation: household air conditioners must be charged almost annually. In fact, a correctly installed split can serve calmly without refueling for 3-5 years, since a large volume of freon cannot flow out through reliable connections.
If the above symptoms are observed frequently, you need to disassemble the joints and check the quality of the rolling. Factory marriage inside the units is a rarity even for the "Chinese".
Hence the advice: do refueling when it is really necessary. But you need to clean the air conditioner annually.
Equipment and materials for work
To make an independent refueling of a home split system, buy, or better, rent a small set of equipment:
- two-stage vacuum pump equipped with a check valve;
- manometric manifold with inspection window and a set of hoses;
- electronic floor scales;
- open-end wrenches and hexagons 5–8 mm in size (possibly found in the household).
Note. Pump models equipped with a non-return valve do not “throw” their own oil into the freon lines during operation.
Next, you need to choose the right freon for the air conditioner, being guided by the factory nameplate on the external unit or the cooler instruction manual. The label indicates the brand of refrigerant and the charging rate, expressed in kilograms (or grams).
When choosing a type of freon, use simple recommendations:
- Buy the freon indicated on the tag, other brands will not work. The most common two-component gas is R410a, less common is R22 or R134a (in cars). Freon R12 is considered obsolete and therefore discontinued.
- When renting a manometer manifold, be sure to tell the brand of refrigerant used. The device and hoses that worked with R22 freon cannot be used to fill the R410a gas, since different oils have been added to them - on a mineral and synthetic basis, respectively.
- A special adapter is used to connect the gauge station to the service ports of the split system working with R410a refrigerant.
- Calculate the weight of the refrigerant with a margin. Approximately 50 grams plus 30 g for each extra meter of pipelines will take to purge the hoses if their length exceeds 3 m.
- For most air conditioners installed in apartments, 1 kg of freon is sufficient, taking into account the stock. You can rent it with a cylinder or buy in a separate container.
Some types of cylinders have a built-in siphon shown in the diagram. Such tanks do not need to be turned over to fill the freon in a liquid state. Check with the seller or lessor for the type of bottle.
Clarification. Cylinders charged with R410a gas are colored in pink, R22 freon in green.
There is a specialized electronic device that detects minor defects in pipes and joints - a freon leak detector. If the cooling efficiency has decreased, but there are no obvious leaks in the air conditioner, the meter will help you find a fistula the size of a human hair. If necessary, the device can be rented, bought - expensive and pointless.
Cost savings compared to calling a wizard
Knowing the need for materials and equipment, it is easy to calculate how profitable do-it-yourself air conditioning refueling is. We take the rental price on the Internet resources of companies offering this service in the Moscow region:
- vacuum pump + manifold with hoses - 700 rubles. per day (12.5 cu);
- a complete set, including a gas cylinder, gauge station and pump, from 1000 rubles / day (18 cu);
- the most expensive type of freon - R410a - 650 rubles. for 0.6 kg (12 c.u.).
Note. Prices are as of March 1, 2018. The equivalent is given in parentheses in parentheses, since the cost of services varies over time.
We take into account the more expensive option - equipment rental plus purchase of freon: 700 + 650 = 1350 rubles. (24.5 cu. The minimum cost of refueling split systems declared by various companies is 2000 rubles. (35 cu. The benefits of self-refueling are not very high - 650 rubles or 10.5 cu.
Consider a number of conflicting factors:
- To rent equipment and devices, you need to spend personal time.
- The prices indicated on the Internet can be underestimated in order to attract customers or simply become outdated.
- Often a company charges additional expenses for departure or bills for each work separately - vacuum, diagnostics and refueling.
- There is a possibility that the "cheap" masters will do poor quality work and a year later the freon will disappear again.
- The cost of renting electronic scales has not been taken into account. It is possible to use tabletop kitchen scales designed to measure weight up to 20 kg with a display accuracy of up to 1 gram.
Hence the conclusion: correctly made self-injection of freon is preferable to contacting a company that provides low-cost services. The work of experienced professionals is expensive.
Refrigerant Weight Charging Technology
The essence of the method is the complete replacement of freon - the old gas must be lowered into the atmosphere, and instead of it pour fresh freon. For beginners, this is the most acceptable option - only an experienced master is able to determine the remaining refrigerant in the system and accurately refuel the missing amount. Other download methods will be described below.
Tip. Before refueling, fix the problem that caused the loss of old gas. Ideally, the split system should go through a pressure test with nitrogen injected at the maximum pressure specified in the product data sheet (usually 25-30 Bar).
We present instructions on how to fill the air conditioner with freon by weight:
- Drain the old freon into the atmosphere in any convenient way - through a unscrewed tube or a service port spool. Release gas slowly so as not to lose oil. While emptying, open both taps hidden under the protective nuts.
- Close the taps and connect the left hose of the gauge station (blue) to the spool. Make sure the manifold valves are closed too.
- Connect the middle yellow hose to the union of the vacuum pump, start the unit. Open the left low-pressure valve (on the left in the diagram) and follow the vacuum gauge - the arrow should drop below zero and show a value of minus 1 Bar. Also open the service port valves.
- Vacuum the freon circuit for 20 minutes. After the pump stops, wait half an hour observing the pressure gauge. If the arrow moves back to zero, look for a leak.
- Switch the hose from the pump to the cylinder, close the left manifold tap. Open the reservoir valve a few turns and purge the hose with freon. The operation is simple: open the right gate valve of the station (high pressure) for 1 second.
- Set the cylinder properly on the scale and reset the display. Open the left manifold valve again and monitor the decrease in gas mass. When the display shows the required amount of refrigerant, close the tap.
- Shut off both valves on the service ports, disconnect the nozzle from the spool and check the split system for proper operation.
An important point. Freon R410a is poured only in a liquid state, so the cylinder is placed on the scales upside down. During refueling, overflow of matter is easy to see in the inspection window of the collector. If the tank is equipped with a siphon or R22 refrigerant is pumped in, there is no need to turn the bottle over.
Other gas injection methods
Since the complete replacement of gas involves certain costs, the master refrigerators use the following methods of refueling freon in a split system:
- overheating temperature;
- by freon pressure in a working air conditioner;
- compressor current consumption.
For adding refrigerant, it is very important to understand how much gas is left in the circuit, compressor and both heat exchangers. Only the first method gives an exact answer: using a contact thermometer or a remote pyrometer, the actual temperature of freon is measured with the compressor running and compared with the value of the desired scale (the boiling point of the corresponding refrigerant) printed on the station’s pressure gauge.
If the difference between the real temperature and the value indicated by the arrow on the scale exceeds 8 degrees, there is not enough freon in the circuit. The master adds refrigerant in small portions and measures the temperature again. When the difference is less than 5 ° C, refueling takes place - you need to vent excess gas.
Since the pressure of the refrigerant and the current in the compressor circuit depends on many factors and is constantly changing, it is unrealistic to accurately determine the amount of freon. We do not recommend beginners to use these methods, so as not to disable the most expensive unit - a compressor.
Last Tips
Most likely, independent refueling of the split system will not bring much financial gain, only moral satisfaction and experience that will be useful in the future.In order not to make mistakes, listen to the following recommendations:
- Pay close attention to leak detection and evacuation. It is better to spend time reworking the rolled compounds of copper tubes than to lose freon again.
- Take your time and remember to close the valves in the correct sequence.
- Blowing out air hoses is strictly mandatory - moisture and oxygen cannot enter the circuit.
- Before disconnecting the hoses from the air conditioner, close the cylinder valve and let the remainder out of the nozzles through the gauge station.
The master refrigerator will take no more than an hour to fill, you should allocate twice as much time to complete the work. Check out the R22 brand Freon download instructions in the last video.