Clean the instrument dial cover with soap, water and facial tissues. Crystal via dial-plastics and solvents fog. If the system has a leak vacuum produced will not be high vacuum. Dial, the arrow will grow when the valves are closed. Moisture in the system will cause the vacuum produced less than desirable. When the valve is closed, a set of needles will rise and fall. Stabilizes at a pressure corresponding to the water vapor pressure at this temperature. They are made with the valve vacuum pump is closed.
The following procedure provides a complete dehydration (drying) humid internal system. Connection 250 VA (250 W) lamp (instead of a fuse in series with the test cord. Attach the cord to the startup of the compressor and terminals. Connecting to a 120V outlet. Since the function lamp resistor, this procedure allows only about 30 V go through the running of the windings. Compressor windings are warmed. Any moisture that may be trapped in the system evaporates. The compressor should not run during this operation.
If the collector is used, it must be degassed.
This is achieved by pulling a vacuum on it for several days. The procedure removes all the vapour is absorbed into the walls and cracks in the collector. (These residual gases can make you believe that there is a leak in the system.) Evacuate the system as high side and the low side.
Use as a large-diameter vacuum line as possible. Keep the vacuum line as short as possible. Vacuum pump dimensions are given in cubic feet per minute (cfm):
1.5 cfm (good for 3-and 5-ton domestic systems).
3-5 cfm (from 5 to 100 tons and medium-sized systems).
10-15 cfm (large systems (more than 100 tons).
Always break vacuum (allow air into the vacuum pump before it is stored. Otherwise the cylinder will fill with oil and become blocked oil (hard to turn). Schedule for the different factors that can be performed with different types of pumps. Please note the temperature of boiling of water at different pressures.
In the process of manufacturing systems evacuated 50 mm to 100 microns to add oil. In the field of oil already in the squad. Evacuate up to 50 microns may cause some oils evaporate. Motor compressor depends on gas consumption for cooling the motor and the compressor. Therefore, you should avoid using it as a vacuum pump. The motor-compressor can overheat and be damaged.
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