High and low temperature test chamber refrigerant leakage site

High and low temperature box refrigerant leakage location one, air conditioning evaporator leakage air conditioning evaporator upper and lower two sides of the welding port is more, will appear more leakage points
.

The newly installed air conditioner leaks, the key reason is that the air conditioner manufacturer staff welding process is poor, in the absence of the air conditioning copper pipe burned red (the temperature did not exceed 600 ° C ~ 700 ° C), the welding wire was placed at the welding port, the air conditioning copper pipe and welding materials failed to melt together, resulting in welding welding, hemp slag, convex and concave uneven
.

Newly installed air conditioner, open the air conditioning outdoor unit cut-off valve, after clearing the air conditioning indoor unit gas, the sound of the air conditioning indoor unit air conditioning evaporator leakage can sometimes be heard in the ear, you can see the air conditioning unit leakage, the air conditioning evaporator spot welding is not to be ignored
.

Found that the air conditioner evaporator leaked, * good to remove the welding welding
.

In order to prevent the heat flame, the plastic shell of the air conditioner evaporator is baked and deformed, and it is impossible to explain
to the customer.

The way to disassemble and assemble is: (1) Select the leak point and do a good job of marking
.

(2) If there is also refrigerant in the refrigeration unit, the refrigerant should be stored in the outdoor unit of
the air conditioner.

(3) Use 2 8-inch or 10-inch wrenches to remove the coupling lock female of the air conditioner indoor unit, and remove the electrical equipment box
on the right side of the air conditioner indoor unit.

(4) Remove the fixed pipe and straight hair splint behind the air conditioner evaporator, and remove the air conditioning evaporator in the room to accurately locate the screws
up and down.

(5) The right hand gently extends the pipe 20 from behind the air conditioner indoor unit to move
the air conditioner evaporator forward.

After dragging the air conditioner evaporator out of the 5cm with your left hand, turn the air conditioner evaporator 90 degrees with both hands and drag it out along the
pipeline.

Pay attention to the actual operation of both hands, and do not knock down
the plate wing.

After the air conditioner evaporator is removed, it is placed in a leveled and clean area, and the leaked oil stains are wiped clean with a
damp cloth.

The leakage point is welded with silver welding, and after the pressure inspection is clear that there is no leakage, the air conditioning evaporator is installed back on the plastic structure of the air conditioner indoor unit according to the
reverse order of disassembly.

Second, the air conditioning indoor unit junction leakage Air conditioning unit runs everything normally, and the air conditioning indoor unit does not have a air conditioner blowing out, indicating that the refrigeration unit has common faults
.

If you find that there are oil stains at the junction of the air conditioner indoor units, it means that the refrigerant leaks
here.

First use 2 wrenches to tighten the "nano" at the junction, and then rub out the foam plastic with washing essence to coat it, and check whether there are bubbles blowing out
at the junction.

If not, it is possible to add R22 vapor refrigerant from the double circuit power supply of the bottom pressure gas valve, with a bottom pressure of 0.
5MPa as the standard
.

Shut down with scrubber and then check the nano, 3 to 5 minutes later there are still no bubbles caused, indicating that the common fault of air leakage at the junction is cleared
.

If the leak is caused by R22 bubbles with washing fine test, it indicates that there is a crack or damage in the flared mouth period of the pipeline, and it is necessary to make the flared mouth period
again.

Before making, first connect the switching power supply, use the controller to set the cooling situation, and let the refrigeration compressor run for 5 minutes
.

Then close the bottom pressure liquid gate valve first, and then close the bottom pressure gas valve after 40 to 50 seconds
.

At this time, touch the off button of the controller with your hand to stop the air
conditioner.

Use two 10-inch wrenches to twist open the lock mother at the junction of the air conditioner indoor units, check the level of destruction of the horn mouth and analyze the cause of the leak, so that it has accumulated a lot of maintenance work experience
.

The practice of the flared mouth period is to remove the original destroyed flare period with a cutting knife, and then put the air conditioning copper pipe into the clamp of the rising tube of the same caliber of the special pipe riser, and tighten the nuts on both sides
.

The upper mouth of the air conditioner copper pipe should be higher than 1/3 of the steep slope depth during the flared mouth period, and the air conditioning copper pipe mouth should be filed with
a blade holder.

And remove the burr
inside the branch tube.

Use a thin cloth to dip the copper chips in the copper pipe of the air conditioner to prevent the copper chips from penetrating into the refrigeration unit and causing the filter device to block and expand
the common faults.

After watching the branch pipe leveling, then press the expansion cone head of the top pressurer on the branch pipe, hold the rising tube barrel clamp with the right hand, twist the rising pipe cone head rocker of the screw with the left hand, the posture should be symmetrical and slow, spiral into 3/5 because, and then rotate back 2/5 circles, and continue to carry out until the branch pipe can be expanded into a 90o+0.
5 flared port period
.

This type of operation procedure makes the flared mouth round, smooth and crack-free
.

What should be noted during the rising speaker period is that the collet must be pinched rigidly in the air conditioning copper pipe, otherwise when the mouth rises, the air conditioning copper pipe is very easy to move to the right, resulting in insufficient height to width ratio or tilt in the speaker period, and it is still very easy to leak the refrigerant
after connection.

After the horn is made, the lock mother is screwed with her finger and then twisted
according to the torque regulations with the wrench.

After the pipeline is connected, how to discharge the air conditioner evaporator and the gas outside the joint pipe is a practical operation stage
that novices must grasp.

If the exhaustion is not very good, the system software mixes a lot of gas, which will cause the abnormal operation of the entire refrigeration unit to cause common faults
such as reduced air conditioning cooling capacity, expansion of current flow, rising working pressure, and reduced service life of refrigeration compressors.

The water in the gas enters the system software and causes an exothermic reaction with the refrigerant, which will increase the corrosion of the system software, promote the embrittlement of the electromagnetic coil of the refrigeration compressor, destroy the compressive strength of the insulation layer, increase the opening flash point of the grease, and reduce the service life
of the refrigeration compressor.

Therefore, removing the gas in the air conditioner evaporator and the pipeline is an important part
that the maintenance staff must grasp.

The way of the exhaust pipe is: loosen the bottom pressure vapor lock female half circle, use the hexagonal wrench to open the bottom pressure liquid cut-off valve for about 1/2 turn, hear the "hissing" sound from the bottom pressure vapor nano, and immediately close
.

When the "hissing" sound of the bottom pressure vapor cut-off valve subsides quickly, then open 1/2 turn of the bottom pressure liquid cut-off valve, close it immediately after 15s, and continuously operate 3 times to discharge
the gas.

The frequency of specific steps and the length of time should be mastered
depending on the size of the air conditioner evaporator and the length of the pipe.

Some maintenance workers do not loosen the bottom pressure vapor lock mother when exhausting, but discharge the gas from the bypass valve nozzle, which is not available
.

Third, the air conditioning outdoor unit cut-off valve core leakage air conditioning outdoor unit cut-off valve core leakage most of the time after the transfer of the machine, because the switch valve hinge to spiral in, spiral out, plus the silicone ring for a long time brittle, the shaft sealing silicone ring grinding, resulting in the cut-off valve leakage, with washing fine leak detection, can be found 3 minutes up and down 1 small bubble
.

In the resealing cap, add 1 rock wool and glass magnesium round pad to remove the common faults of small leaks
.

If the leakage is more serious, you can hear the sound of "hissing", you can discharge the refrigerant
from the bottom pressure vapor lock mother of the outdoor unit of the air conditioner.

During the discharge, there should be a refrigerant with a working pressure of 0.
1MPa left outside the tube to avoid the inconvenience
of the system software entering the gas and generating vacuum packaging.

The operation step is: the cut-off valve limit switch snap ring, with the sharp nozzle pliers to remove
.

Use the hex wrench to rotate out the shut-off valve screw, the right hand plugs the leaky place, the left hand quickly surrounds the 4-circle raw tape at the screw and sealing ring of the screw, and quickly rotates the shut-off valve screw to prepare the jam ring
.

Then wrap the raw tape around the re-sealing wire for 2 to 3 turns, and prepare the re-sealing cap
.

Add F22 refrigerant from the bottom pressure vapor to the intake valve gas filling, and when the gauge pressure exceeds 0.
3MPa, start with the controller, and add R22 vapor again to 0.
45MPa
.

When refueling, it should be added slowly, and there is no need to rush to prevent R22 vapor from being released more, so that the maintenance cost will rise
。
After the R22 vapor is added according to the regulations, the air conditioner is terminated for 3 to 5 minutes
.

After the cooling vapor in the system software is balanced, the working pressure rises, and the leakage
is measured at the 2 times of sealing outer cap with washing essence.

It is determined that there is no water leakage, indicating that the raw tape around the screw of the cut-off valve has excellent sealing, and the common faults of leaking steam are removed
.

Fourth, the outdoor refrigeration compressor U-shaped pipe leakage outdoor refrigeration compressor U-type exhaust pipe leakage is more extensive, the key reason is that the air conditioning copper pipe wall thickness, poor material, after bending into a U-shaped bend, there are small cracks, refrigeration compressor in the work caused by vibration to increase
the crack.

Most of the common faults of this kind of leakage will transmit the vapor, and when the air conditioner indoor unit is blown out without wind, it will be found
after inspection.

The maintenance method is: wipe the oil stain of the leak point with a thin cloth to the net, and use silver welding to weld the crack leakage of the copper pipe of the
air conditioner.

Before welding and welding, it is easier to find each section of the air conditioning copper pipe with a diameter of more than the exhaust pipe, saw it open with a hacksaw, and the bag is at the crack to avoid leakage
from vibration from here.

Do not remove the U-shaped pipe during maintenance, which will make the ultra-high pressure refrigerant vapor discharged from the refrigeration compressor immediately enter the cooler, so that the cooler heat pipe heat dissipation is reduced, the cooling work capacity is reduced, and together, the refrigeration compressor vibrates greatly
when it works.

After the U-shaped pipe is welded, the R22 vapor is added from the bottom pressure vapor to the valve bypass valve nozzle
.

Water pressure test leak measurement, if there is no bubble blowing out from the welding port, indicating that the U-shaped pipe leakage common fault clearance
.

Fifth, the air conditioning outdoor unit capillary vibration wear leakage air conditioning machine does not cause cold, refrigerant leakage, there will be vibration caused by the refrigeration compressor when doing work, so that the 2 water pipes cause resonance friction, the wall thickness is worn out, so that the refrigerant is transparent
.