What is the construction process of radiant floor heating
I. Construction preparation
Prepare pipes and insulation boards before construction , design drawings, construction plans and other necessities. Note that when the construction object shares the same central heat source water system with other heating systems, and other heating systems use corrosive components such as steel radiators, the pipes should have an oxygen barrier layer to effectively Prevent the penetration of oxygen and accelerate the oxidative corrosion of the system.
Second, fixed sub-catchment
1. Before floor heating construction, the floor leveling layer should be inspected.
2. The sub-catchment is horizontally fixed on the wall with 4 expansion bolts, and the installation should be firm.
Third, laying the insulation layer
1. Paste the 10mm edge and corner insulation board along the wall with latex, and it is required that the paste is smooth and the overlap is tight.
2. Lay a thermal insulation layer on the leveling layer, glue the joints firmly, and lay aluminum foil paper or a composite aluminized polyester film with coordinate grid lines on the floor heating thermal insulation layer , the insulation layer should be laid flat.
3. Lay a layer of Ф2mm steel mesh on the aluminum foil paper, with a spacing of 100×100mm and a specification of 2m×1m. Steel nails are fastened to the floor. The room with waterproof layer, such as bathroom, kitchen, etc., is not allowed to be nailed when fixing the steel mesh. When the pipe or steel mesh is warped, measures should be taken to prevent the pipe from exposing the concrete surface.
Fourth, laying buried pipes
1. Install the heating pipes (PEX-A pipes) according to the spacing required by the floor heating design, and use plastic pipe clamps to connect the pipes Fixed on the benzene plate, the distance between the fixed points, the distance between the elbows is not more than 300mm, the distance between the straight sections is not more than 600mm, and the ends and midpoints of the curved pipe sections greater than 90° should be fixed. The bending radius of the pipe should not be less than 8 times the outer diameter of the pipe. During the installation process, it is necessary to prevent the pipeline from being polluted. After each loop heating pipe is laid, the nozzle should be blocked in time.
2. After checking whether the heating pipes laid by the floor heating are damaged and whether the pipe spacing meets the design requirements, carry out the hydraulic test, and inject clean water from the water injection and exhaust valve to conduct the hydraulic test, and the test pressure is the working pressure. 1.5 to 2 times, but not less than 0.6Mpa, the pressure drop within 1 hour of pressure stabilization is not more than 0.05Mpa, and no leakage or leakage is qualified.
V. Set expansion joints
When the side length exceeds 8m or the area exceeds 40m2, expansion joints should be set. The size of the joint is 5~8mm, the height is the same as the fine stone concrete cushion. When the plastic pipe passes through the expansion joint, a flexible sleeve with a length of not less than 400mm should be provided. Where the water divider and heating pipes are dense, the outside of the pipe should be protected by a corrugated pipe of not less than 1000mm to reduce the thermal expansion of the concrete, and at the same time, the joints should be filled with elastic expansion paste.
Six. Intermediate acceptance
The ground radiant heating system shall be subject to intermediate acceptance according to the construction characteristics of the project. The intermediate acceptance process starts from the pressure test after the heating pipe laying and the installation of the heat medium separation and water collector devices, and the pressure test is carried out again after the curing period of the concrete filling layer is completed, which shall be carried out by the construction unit and the supervision unit.
Seven, backfill concrete layer
After the heating pipe is qualified, backfill with fine stone concrete, and the heating pipe should maintain a pressure of not less than 0.4Mpa; Manual wiping and compaction, do not use mechanical vibration, do not step on the laid pipeline, when the fine stone concrete is close to the initial setting, the surface should be tapped and pressed twice to prevent plastic shrinkage cracks along the axis of the pipeline. . The surface should be moisturised and maintained for more than 14 days after pressing and wiping. After the cushion reaches the curing period, the pipeline system is allowed to release pressure.
VIII. Completion acceptance
1. During the completion acceptance, the following documents should be available:
①Construction drawings, as-built drawings and Design Change Documents.
②The inspection certificate and factory certificate of main materials, parts and components.
③Intermediate acceptance record.
④Pressure test and flushing records.
⑤ Engineering quality inspection and evaluation records.
2. Completion acceptance criteria:
① Completion quality conforms to design requirements and relevant provisions of this Regulation.
②There should be no obvious cracks on the surface of the filling layer.
③There is no leakage of pipes and components.
④The valve opens flexibly and closes tightly.
Technical specification for ground radiant heating system
1. Ground heating construction
1. Renovation required The company carefully prepares the leveling layer, and the surface should be smooth and free of debris.
2. The thermal insulation layer requires that the thermal insulation material be laid evenly and evenly to meet the requirement of (25/m3) density.
3. The radiation anti-corrosion layer material (non-woven aluminum foil paper is used) should be laid flat to ensure the lap length.
4. When installing and laying geothermal pipes, it is required to use pipe clamps to fix the geothermal pipes to ensure the spacing of the geothermal pipes, and the bending arc of the geothermal pipes shall not be less than 10D.
5. Lay the steel mesh at the end, the fixing card should be installed firmly, and the displacement should not exceed 30mm.
Second, project inspection and acceptance
1. After the construction of the heating project is completed, the company should organize a special person for self-inspection.
2. On the basis of self-inspection, Party A’s representatives are invited to conduct inspection and acceptance.
3. Under the supervision of Party A, conduct a water pressure test on the system, the test pressure is 6.5mPa, and the pressure drop does not exceed 0.05mPa in 15 minutes to qualify.
4. Do a good job of concealed engineering testing and acceptance records, and file all engineering signature documents.
III. Construction standards of civil engineering
1. The local 425# cement concrete covering layer shall be used, and the strength shall not be less than C15.
2. Add a covering layer, the thickness of the covering layer should not be less than 30mm-40mm.
3. When the room area exceeds 40m2 or the length exceeds 6m, expansion joints should be set.
4. For the parts that the decoration company needs to nail, mark them with red paint on the ground, so as to facilitate the installation of geothermal pipes and avoid obstacles.
5. After the project is completed, thoroughly clean up the site and remove all temporary facilities on the ground on the construction site. The construction process of geothermal heating system: pre-construction preparation → engineering materials entering the site for inspection → laying insulation board and aluminum foil paper laying and reinforcing steel mesh → cross-linked pipe loop laying → installation of system water separator heating system installation → water (gas) Pressure measurement → handover project to Party A
4. Other regulations
1. The supply and return water temperatures of the low-temperature hot water ground radiant heating system should be Determined by calculation, the water temperature should not be greater than 60 ℃.
The temperature of water supply for civil buildings should be 35~50℃, and the temperature difference between supply and return water should not be greater than 10℃.
2. The calculated value of the average temperature of the ground surface shall meet the requirements in Table 3.1.2.
3. The working pressure of the low-temperature hot water ground radiant heating system should not be greater than 0.8Mpa; when the height of the building exceeds 50m, it should be set in vertical partitions.
4. No matter what kind of heat source is used, the parameters such as temperature, flow and resource pressure difference of the low-temperature hot water ground radiant heating heating medium should be matched with the heat source system. The heat source system shall be provided with corresponding control devices.
5. The content and depth of the construction drawing design documents of the ground radiant heating project should be based on construction drawings, including drawing catalogues, design instructions, layout plans of heating pipes or heating cables, and layout of temperature control devices Figure and water distributor, water collector, ground structure schematic diagram, etc.
The design description should explain in detail the calculated temperature inside and outside the heating room, parameters of heat source and heat medium or power distribution scheme and technical data and specifications of electric load, heating pipe or heating cable; indicate the specific conditions of use such as working temperature , working pressure or working voltage and thermal conductivity, density, specification and thickness of thermal insulation materials.
The specific arrangement of heating pipes or heating cables should be drawn on the plan, and the laying spacing, pipe diameter of heating pipes, calculated length and requirements for expansion joints should be indicated.
6. When using the heating cable ground radiant heating method, the line power of the heating cable should not be greater than 20W/m.
