Repair And Maintenance Of Heat Recovery System
1, Daily maintenance (daily/weekly)
1. Operational parameter inspection (daily)
Monitor the temperature, pressure, flow rate, and temperature difference between the inlet and outlet of the heat exchanger for fresh/exhaust air (normal 5-15 ℃).
Observe the current, vibration, and noise of the fan, and immediately stop the machine for inspection if there are any abnormalities.
Check if the condensate drainage is smooth, without water accumulation or odor.
2. Appearance and safety inspection (weekly)
Check for leaks, rust, and deformation in the equipment casing, pipelines, and flanges.
Check the differential pressure of the filter and prepare for replacement in advance when it approaches the upper limit.
Confirm that the control cabinet indicator lights and alarm functions are normal.
2, Quarterly maintenance (every 3 months)
1. Air filter maintenance (core)
Remove the primary/medium efficiency filter, clean or replace it; Replace every 1-2 months when pollution is severe.
Clean the filter frame and sealing gasket to ensure no air leakage.
2. Fan and transmission system
Check the tightness and wear of the belt, adjust or replace it; The appropriate tension is to press down by 10-15mm.
Add high-temperature lubricating grease to the bearings to eliminate abnormal noise and reduce temperature rise.
Check the insulation and wiring terminals of the motor, and tighten any loose parts.
3. Valves and dampers
Manual/electric testing of fresh air valve, exhaust valve, and bypass valve, with flexible operation and good sealing.
Clean the actuator and connecting rod, and add lubricating grease.
4. Condensed water system
Clear the drainage pipeline and collection tray, remove sludge and mold, and prevent blockage and corrosion.
Check the operation and start stop control of the drainage pump (if any).
3, Annual in-depth maintenance (once a year)
1. Deep cleaning of heat exchanger (core)
Plate/fin type: Remove and wash the heat exchange core, rinse with low-pressure water and neutral cleaning agent, and prohibit wire brushes/high-pressure water; Vacuum cleaner removes floating dust.
Wheel type: low-pressure spray+soft brush cleaning of the wheel surface; Check if the moisture absorbing coating is damaged; Calibrate the speed to 8-12 rpm.
Heat pipe/tube type: mechanical cleaning+chemical cleaning of scale/crystallization; Check the fins for lodging and correct them.
2. Sealing and air leakage control
Check the sealing strips around the impeller/heat exchanger, replace them immediately if they have aged or hardened (silicone/fluororubber).
Detect the air leakage rate of the shell and pipeline, and repair and reinforce it if it exceeds the standard.
3. Sensors and Control Systems
Calibrate temperature, humidity, pressure, and differential pressure sensors, and replace them if drift exceeds the tolerance.
Test PLC/controller, interlock logic, alarm function; Upgrade/backup program.
Check the wiring, terminals, grounding, rust removal, fastening, and insulation testing.
4. Pipeline and anti-corrosion
Inspect pipelines, supports, and expansion joints, repair corrosion and cracks, and apply anti-corrosion coatings.
Test the pressure resistance and sealing performance of the testing system (water/air pressure test).
5. Other components
Check the muffler and shock absorber, replace them if they are damaged.
Clean the dust inside the control cabinet and frequency converter, and check the cooling fan.
4, Key points for different types of heat recovery equipment
1. Rotary heat recovery
Calibrate the speed every quarter, and deviations affect efficiency.
Regularly start for short periods during long-term shutdown to prevent uneven moisture absorption and imbalance.
Hospitals/laboratories and other high pollution environments: Clean the wheels monthly.
2. Plate/fin type
2000 hours of vacuum cleaning operation; Dismantle and wash every year.
It is strictly prohibited to collide with hard objects to prevent the fins from collapsing and the plates from deforming.
3. Flue gas/industrial waste heat recovery
Focus on cleaning dust, preventing acid corrosion, and controlling wall temperature to avoid acid dew points.
Check the flue, expansion joint, and wear-resistant lining every quarter.
Conduct annual wall thickness testing and weld seam inspection.
