In cleanrooms and ventilation systems, HEPA panel filters are the core defense for ensuring air cleanliness. However, accurately determining the replacement timing and performing standardized replacement procedures is crucial for ensuring the system’s continued effective operation. Blindly replacing filters leads to waste, while delayed replacement results in decreased cleanliness and soaring energy consumption.
Determining Replacement Timing
Differential pressure monitoring is a key indicator; filter replacement decisions should be based on data, not subjective guesswork. Differential pressure monitoring is the most fundamental and objective basis for judgment.
- 1. Initial Pressure Drop: The differential pressure value recorded when the system is running stably after installing a new filter. This is the baseline for all judgments.
- 2. Final Resistance Differential Pressure: The differential pressure value at which the filter needs replacement when the dust accumulation reaches the design dust holding capacity. Usually recommended by the filter manufacturer, it is generally 1.5 to 2 times the initial differential pressure.
- 3. Real-time Monitoring and Early Warning:Monitoring Method: Install differential pressure gauges or sensors before and after the filter for continuous monitoring.
Critical Point: When the measured differential pressure reaches or approaches the “final resistance” value, the system should issue an early warning, prompting replacement.
Trenntech Solution: In many high-standard facilities in Munich, Germany, we often integrate differential pressure sensors with digital displays and remote monitoring modules into our clients’ HEPA systems to achieve predictive maintenance.
Auxiliary Judgment Basis (must be combined with differential pressure data):
Cleanliness Test Failure: Particle counter detection shows a continuous decline in cleanliness level.
Visual Inspection: Where permissible, inspect the filter surface for irreparable damage or abnormal stains.
Usage Time: In low-contamination environments, this can be used as a reference, but should never be the sole basis for judgment.
II. Standardized Replacement Procedure Incorrect installation can lead to leaks, rendering the expensive filter useless. Please strictly adhere to the following operating procedures:
Preparation:
- 1. Safety First: Turn off the system power and lock the doors, ensuring the fan is completely stopped. Wear appropriate personal protective equipment.
- 2. Environmental Cleaning: Pre-clean the installation area and prepare tools and the new filter (unpack in the cleaned area).
- 3. Marking and Recording: Record the old filter’s serial number, location, final differential pressure, and replacement date.
Replacement Procedure:
- 4. Removing the Old Filter: Carefully loosen the securing devices, support the filter frame with both hands, and remove it smoothly. Immediately place it in a prepared plastic bag and seal it to prevent dust generation.
- 5. Thoroughly Clean the Mounting Frame: Use a non-woven cloth and a specialized cleaner (such as isopropyl alcohol) to thoroughly wipe the sealing surfaces of the mounting frame, ensuring no dust, oil, or old gasket residue remains.
- 6. Installing the New Filter: Inspect the new filter’s appearance and the gasket for damage. Verify the airflow direction arrow to ensure it aligns with the system’s airflow direction. Support the filter with both hands and smoothly and vertically insert it into the mounting frame, ensuring even pressure and proper gasket compression.
- 7. Tightening and Verification: Evenly tighten all securing devices.
The most crucial step: After replacement, a site-wide leak test must be performed to confirm the installation is leak-free before restarting the system.
III. Professional Advice: Choose a reliable and high-quality supplier with excellent service.
A successful replacement relies on high-quality products and professional support.
- Choose reliable products: Select suppliers like Trenntech that provide complete performance reports and clear final resistance recommendations.
- Obtain professional guidance: Excellent suppliers can provide installation guides, differential pressure setting recommendations, and even on-site training.
- Establish replacement records: Create a maintenance record for each filter to achieve full lifecycle management.
Scientifically judging and standardizing the replacement of plate HEPA filters is a rigorous process based on data monitoring and standardized operations. It not only ensures your clean environment is flawless but also significantly reduces the total cost of ownership by optimizing replacement cycles. Proper maintenance is the ultimate guarantee for realizing the performance and value of the filter.