The core problem of compressor oper
8 main points of HVAC field construction experience
1. Equipment installation
1. The installation location of the air-conditioning host should be convenient for inspection and repair, and should not affect its use function, especially pay attention to heat dissipation. When there are multiple hosts in the computer room, all the host take-over directions and operating surfaces must be in the same direction;
2. The base of the terminal equipment is uniformly made of channel steel, and the channel steel specifications are determined according to the weight of the equipment but not less than No. 10 channel steel;
3. The installation position of the fan coil is 150mm away from the wall, 200mm away from the window, and 300mm away from the wall behind the pipe (the size after the return air box is reduced). When the ceiling size is large enough, the coil can be installed horizontally with the air duct. If the ceiling space is not high enough, the coil should be installed on the floor as much as possible (the drainage height must be reserved);
4. The serial number of the air-conditioning main unit and fan coil must be copied correctly, and the random data must be kept intact;
5. Don't damage the equipment during transportation and installation, especially the mainframe paint, fins, and the condensate pan, socket, impeller, etc. of the fan coil;
6. The junction box, condensate pipe connection, and water inlet and outlet connections of the fan coil unit must be in the same direction to facilitate future maintenance; if the fan coil unit is connected to the return air pipe, the motor must be removed when an inspection hole is opened at the bottom of the return air pipe for easy maintenance;
7. The installation position of the equipment must be correct, and the equipment must be installed in a flat installation;
8. The coiled pipe and the screw rod of the hoisting support hanger shall not be less than 8mm;
9. Electric two-way valves or proportional integral valves must be installed on the outlet pipes of all terminal equipment;
10. All equipment import and export must be equipped with soft connection shock absorber;
11. A shock-absorbing rubber sheet or shock absorber must be pre-padded on the equipment base;
12. A galvanized flat iron must be welded to the base of the equipment to connect to the lightning protection ground wire of the building. For example, in the machine room, all hosts, water pumps, and power distribution cabinets must be connected to the lightning protection ground wire, and the galvanized flat iron must be connected (electrical Construction specification requirements).
2. Wind system
1. The production of the return air box should meet the requirements, the layering should be good, and the insulation should be good; the insulation material should not be damaged during installation;
2. When the return air box is riveted to the fan coil, the return air box must be upright, not to be distorted or twisted;
3. Flange welding should not have missing welding, holes, flange diagonal error less than 3mm, flatness error less than 2mm, flange screw hole and rivet hole distance is specified as 120mm, welding slag must be removed before flange painting, and then Brush the red lead twice;
4. The head of the air pipe adopts the method of socket buckle, the air nozzle (0.05m) is riveted, and sealant must be applied to each place. When the flange is riveted, the flange of the air pipe shall not be less than 6mm, and the four sides shall be consistent;
5. The air supply under the duct must be equipped with a wind baffle, and the wind nozzle must be blunt;
6. The installation of the air duct in the living room is the same for the two fan coils. The air duct and the fan coil are connected by waterproof soft canvas, the length is 200mm, and the single flange is used for crimping;
7. For the installation of the air duct in the master bedroom (side delivery and lower return), the center point of the return air outlet should be on the same plane axis; if the side delivery side return, the return air outlet should be on the same plane;
8. For the fan coils installed on the side of the inclined roof over 2800mm, the air outlet must be installed with a 45-degree (angled) air duct;
9. After the duct is finished, it must be submitted for inspection before heat preservation and installation;
10. When the main air duct's large side exceeds 1000mm, an internal support should be provided at the center of the duct. When the main air duct exits the machine room through the wall, a pipe sleeve and a fire damper must be installed.
Ш Water system
1. The shrinkage of PP-R pipe during hot melting must be less than 3%, and the installation must meet the manufacturer's technical requirements;
2. The pipe must be piped through the wall. PUC70 sleeve for De25 and De32; PUC110 sleeve for De40, De50 and De63; PUC133 sleeve for De75 and De90;
3. Pipe brackets use L30 angle steel indoors with aluminum powder paint for the finish; use L40 angle steel outdoors; channel steel brackets must be used for large pipes. (Above DN150)
4. The pipe supports must be springed before installation, the distance between them is less than 800mm, and they must be evenly divided on the same plane, and the support forms in the same area should be the same;
5. The pipeline installation of the pipeline well should be coordinated with the cooperating unit to avoid cross-effects;
6. The installation position of the pipe support is greater than 150mm and less than 300mm from the PP-R pipe elbow; the pipe support must be installed upright and not skewed;
7. Pre-buried holes must be reserved for the center and center of the pipeline bracket, and the pipeline installation must be horizontal and vertical;
8. After the water pipe is installed, it must be flushed and pressure tested. The test pressure is 1MPa, and the pressure shall not drop after 10 minutes of constant pressure; then the pressure shall be reduced to 0.6Mpa and the pressure shall not drop after 60 minutes of constant pressure. The visual inspection is qualified without leakage. Insulation can only be done after the inspection is qualified; high-level pipeline suppression selects 1.5 times the working pressure for pressure test.
9. The highest point of the chilled water pipe must be equipped with an automatic exhaust valve, and a hose should be connected to the condensate pan of the nearest fan coil or into the condensate pipe; the lowest point of the chilled water pipe should be provided with a sewage valve;
10, PP-R pipe hot melt connection should meet the following requirements:
① The fuser should be selected appropriately, the die head should be intact, and the working temperature should be 230-260 degrees. The fuser can be operated after reaching the set working temperature;
②, special pipe cutters, hacksaws or pipe cutting machines should be used to cut the pipes, the cut section should be free of burrs and burrs, and the cut surface of the pipe must be perpendicular to the pipe axis;
③. Before welding, the dirt on the connecting section of pipes and pipe fittings must be removed to ensure that they are clean, dry and oil-free;
④, control the depth of fusion during fusion to reduce the diameter reduction rate;
⑤. When welding elbows or tees, pay attention to their directions, and use auxiliary signs to clarify their positions in the straight line direction of pipe fittings and pipes;
⑥. When heating, the end of the tube should be guided into the heating jacket without rotation and inserted to the specified depth. At the same time, the tube should be pushed to the heating head without rotation to reach the specified depth, and the heating time should meet the requirements;
⑦. After the heating time is reached, immediately remove the pipes and fittings from the heating jacket and the heating head at the same time, and insert them straight and evenly to the specified depth without rotation, so that a uniform flange is formed at the joint;
⑧, within the specified processing time, the newly welded joint can be slightly corrected, but rotation is strictly prohibited;
⑨. When the pipeline is installed, it must not be twisted axially, and it is not advisable to force correction;
⑩. When the pipeline is installed, the mouth of the pipe that is not closed for the time being must be tightly sealed to prevent debris from falling into the pipe;
Fourth, condensate pipe installation
1. The pipe diameter of the condensate pipe must meet the technical requirements, and the installation must be completed before the internal wall plastering and waterproofing of the civil works;
2. When installing the condensed water pipe, you need to flick the thread (report for inspection), and then use the cutting machine to build the groove, and then hit the wall with a depth of 15mm; the prefabricated board is cut along the board seam, not horizontally; if it is on the beam or cut Slotting on the force wall must be reported to the owner and the supervisor for approval;
3. The installation of condensate pipe must avoid the entrance door of the bathroom, and the distance from the door and window should be greater than 200mm;
4. The spacing between the brackets for the installation of the condensate pipe should be less than 800mm; the exposed part must be insulated (except the tube well); the length of the hose when the condensate pipe is installed should be between 20mm-30mm (the distance between the nozzle and the nozzle);
5. After the condensate pipe is installed, it must be tested for water passing and irrigation. After passing the self-inspection, report to the supervisor for inspection.
Five, electrical installation
1. The distance between the wire and pipe clamps should be less than 600mm, horizontal and vertical, and the length of the corrugated pipe should not be greater than 500mm;
2. The inlet pipe of the wire box of the fan coil must be piped from above;
3, the wire joints must be soldered (in-line pipe joints are prohibited), double-wrapped with insulating tape and waterproof tape;
4. Electrical insulation must meet the requirements;
5. The speed line of the fan coil unit must be connected correctly, and it cannot be mistaken with the zero line.
Six, heat preservation
1. When water pipes are insulated, the joints between the insulated pipe shell and the wooden ring must be brushed with glue and tape;
2. When the air duct is insulated, the heat preservation glue should be evenly brushed, without air holes, the surface should be smooth and flat, and free of dirt; the splicing of the plates must be above the duct, and the joints must be glued;
3. The insulation material must not fall off, crack, damage, etc. The insulation tape must be well bonded and not fall off;
4. When the water pipe is insulated, fill the area where the pipe shell cannot pass through with foaming agent;
5. After the pipeline pressure test is completed, the pipeline well and the wall part of the water pipe should be protected first, and the civil construction should not be affected;
6. After the pipe insulation is completed, the film should be wrapped, and the single pipe should be wound as much as possible. The appearance inspection should meet the requirements.
Seven. Coordination with civil engineering
1. Slots and holes on the wall and the ground must be approved after inspection;
2. The elastic thread adopts a pink thread package, stone=red paint, and no ink fountain;
3. Do not scratch the wall randomly, such as drafting and making unnecessary marks;
4. If the putty is soiled, it should be removed with sandpaper in time; if it is damaged, it should be repaired or compensated in time;
5. The holes in the wall should be square and suitable in size. They must be hit with a chisel moderately. Direct hitting with a hammer is strictly prohibited;
6. It is strictly forbidden to drill and slot in the shear wall and beam without approval;
7. Pay attention to the protection of the finished products of other units, do not stain the walls, ground, and do not damage the waterproof, doors and windows, corners, window corners and other objects;
8. The construction site must be tidy and orderly, the materials must be neatly stacked, the construction waste must be cleaned up in time, no littering is allowed, and it is forbidden to dump waste from upstairs to down;
9. Strengthen cooperation and coordination with civil engineering during construction, and do a good job in site transfer.
8. Relevant regulations
1. The electric hammer must be limited when using the electric hammer. The limit size is 60mm to avoid piercing the roof;
2. Construction safety: safety helmets must be worn when entering the construction site; safety measures must be taken for high-altitude operations; electric tools (cutters, bench drills, etc.) must be checked frequently and used by dedicated personnel;
3. The construction site is not allowed to urinate and urinate anywhere, and offenders will be heavily punished;
4. Only one male person can live in the on-site warehouse;
5. The on-site warehouse must keep people 24 hours a day, and it is forbidden to light a fire to cook;
6. The use of materials should be considered comprehensively to improve the utilization rate, prevent the theft or damage of the materials, and control the material loss to z* low (within the fixed loss);
7. The installation of the same type of house must be consistent (subject to the model house), including the installation positions and methods of equipment, the direction and diameter of the water supply and return pipes, and the direction and diameter of the condensate pipes;
8. A weekly meeting is held every Sunday at 5 pm to report on the construction progress, solve engineering problems, and arrange construction tasks;
9. The project schedule node after confirmation must be completed, otherwise it will be punished according to regulations;
10. Strengthen management, strictly follow the technical disclosure content and relevant specifications for construction, and follow up quality supervision and safety inspection simultaneously to prevent quality accidents and safety accidents;
11. All on-site work must be based on the premise of ensuring the quality and duration of the project to ensure that the construction tasks are completed on time and with high quality.
