Each HVAC repair specialist uses a variety of tools for his work, ranging from ordinary wrenches to a vacuum pump for air conditioning. This device is designed to remove air, excess gases and water vapor from a closed circuit system. In refrigeration, a vacuum pump is used when filling with freon.
If vacuum is not performed before starting the air conditioner, air will accumulate in the pipeline, which in turn will adversely affect the operation of the compressor.
Based on the reviews, the process of its interaction with freon can also be attributed to the negative consequences of air accumulation. As a result, a small amount of acid is released, which reduces the resistance of the insulating properties of the motor.
Based on the purpose, vacuum pumps for air conditioning installation are divided into several types: low-, medium-, high- and ultra-high vacuum. Byprinciple of operation, pumps of physical-chemical and mechanical action are distinguished.
Varieties of vacuum pumps
The following types of vacuum pumps are distinguished:
- Rotor vane. Maximum productivity - 63 liters per second. The highest residual pressure is 0.5 Pa. 2 versions of this unit are adapted to a 220 V network, 2 more - to 380 V.
- Water ring. This vacuum pump is designed to evacuate air from the air conditioner. For the operation of such a unit, a water supply is required. The water ring pump creates a relatively small vacuum and is also common and affordable.
- Membrane. Used mainly in industrial plants. Provides a shallow vacuum. The disadvantage is the need for frequent replacement of valves and diaphragms.
- Spool and oil seal pumps are used in industrial applications.
Selection of pump for vacuuming
The selection of a pump directly depends on the type of equipment with which operations are to be performed. For example, small home or office appliances are serviced by an air conditioner vacuum pump with a small capacity. For industrial coolers, a correspondingly powerful and high-performance pump is used.
When choosing equipment, you should pay attention to the following criteria:
- Residual pressure. This indicator affects the quality of the process (the lower the coefficient, thethe process runs better).
- Engine power. This parameter is important when working with industrial installations.
- Performance. This parameter shows the rate of air withdrawal from the system (number of liters per unit of time).
Vacuum device for air conditioners
The air conditioner vacuum pump can be single or double stage, depending on the type of air conditioner.
The most common is the BBH series for home use. It consists of:
- Engine.
- Mechanism for compressing gas (liquid ring).
- Drive (paddle wheel that drives the ring).
- Cases.
- Nipples: for suction and discharge.
The cast iron body consists of three cavities: for suction, discharge and working. Water is supplied through a hole in the lid.
The principle of operation of the pump is as follows: a vacuum is created by a vacuum, due to this, water boils at low temperatures. Due to the fact that the boiling point of water decreases to the ambient air temperature, the process of evaporation of the liquid in the pipeline takes place. Through evaporation, water is removed from the system along with the remaining air.
Cooling system maintenance procedures
Failure to maintain any equipment may result in personal injury or damage to the unit.
Therefore, every specialist needs:
- Before starting operations, you should find out when the refueling took place.
- It should also be clarified with what performance the cooling device works. Air conditioning vacuum pump may need to be bled before refueling.
- Connect pressure gauges, and trace the change in the system.
- Check lines for oil stains.
- After carrying out the inspection and taking readings from the instruments, decide on one of the possible operations: refuel, refuel, diagnose or refuel with diagnostics.
Sequence for removing air from the system
- First, a manifold with a vacuum gauge should be connected to the filling pipe.
- Then a vacuum pump for the air conditioner is connected to the manifold, provided that the vacuum gauge shows normal atmospheric pressure.
- The process of pumping air continues until the pressure is equal to 0.
- At the end of the process, the pump is not disconnected from the device for several hours.
- When the pressure approaches 1, leave the system for an hour without doing anything.
If the arrow is in the “0” position for 20 minutes, the air is evacuated effectively. In the case when the arrow is raised, but notapproaches 1, the pump needs to be reconnected.
Filling the cooling system without special tools
There are cases when it is possible to install an air conditioner with your own hands without a vacuum pump. The new air conditioner contains approximately 50 grams more than the required amount of freon. Therefore, the first start-up of the cooling system can be made without using the pump. To remove air, open the valve located on the liquid pipe (for no more than 10 seconds).
After this operation, it is necessary to check the tightness of the bolted connections and unscrew the valve again, opening the service port. To open the port, press down on its stem with a key. Next, the service ports are closed and the gas pipe valve is vented. Plugs are installed on the valves.
Homemade air purifier
Due to the cost of the unit, many users have a question: how to replace the vacuum pump for evacuating the air conditioner. Without additional investment, you can assemble a primitive vacuum model from scrap materials.
For this you will need: cuff car pump and an aquarium compressor. Assembly order is as follows:
- First, the autopump is disassembled.
- Then the cuff through which the air is pumped is rotated 180°. This action will allow gas to be pumped in the opposite direction.
- At the end, install a check valve (as ita plastic part from an aquarium compressor is installed). It is installed between the car pump and the hose.
Safety when working with cooling appliances
When using vacuum pumps to charge air conditioners and other repair equipment, the following safety precautions should be followed:
- Carry out any operations in a well ventilated area.
- Use pressure gauges.
- Check unit carefully for leaks.
- Use only serviceable appliances.
- Carefully study the instructions for the unit.
It should also be remembered that devices for repair (refueling, refueling) are selected according to special criteria and depending on the level of specialist training. For example, a two-stage vacuum pump for air conditioners, judging by the reviews, is ideal for the repair of household appliances by professionals, and one-stage ones are for beginners.
