HAF Filter
Technology
Índice de contenidos
- Executive Summary§2
- Chapter 1: Understanding LGR Dehumidifier Challenges§3
- 1.1 The Water Damage Restoration Workflow
- 1.2 Why Air Filtration Matters in Dehumidification
- 1.3 Traditional Filter Limitations
- Chapter 2: HAF Technology Explained§5
- 2.1 What is "High Air Flow"?
- 2.2 Electrostatic Capture Mechanism
- 2.3 Material Science: Microstructured Media
- 2.4 Anti-Microbial Surface Treatment
- Chapter 3: Performance Advantages§8
- 3.1 Airflow Retention Over Dust Loading
- 3.2 Particle Capture Efficiency (MERV 8–11)
- 3.3 Energy Cost Savings
- 3.4 Filter Lifespan & TCO Analysis
- Chapter 4: Application Guide§11
- 4.1 Compatible Equipment
- 4.2 Installation Best Practices
- 4.3 Maintenance Protocol: Why NOT to Wash
- Chapter 5: Deli HAF Filter Specifications§13
- 5.1 Technical Data Sheet
- 5.2 Test Results & Certifications
- 5.3 Customization Options
- Chapter 6: Case Studies§15
- Appendices A–C§16
Resumen y conclusiones clave
In professional water damage restoration, dehumidifier performance directly impacts project timelines and profitability. HAF (High Air Flow) filters represent a breakthrough in balancing two critical — and often competing — requirements: high particle capture efficiency to protect compressor and coils, and minimal airflow restriction to maintain CFM throughout service life.
Qué cubre este libro blanco
- How electrostatic capture works at the molecular and fiber level
- Why traditional pleated filters fail in LGR applications
- Quantified airflow retention advantage: HAF vs. MERV 11/13
- 3-year total cost of ownership (TCO) analysis
- Proper selection, installation, and maintenance protocols
- Compatible equipment guide: Dri-Eaz LGR 700, Phoenix, AlorAir, and others
About Deli: 30+ years manufacturing air filtration products for Gree Electric, Freudenberg, Philips, and customers in 50+ countries. ISO 9001:2015 certified since 2005. 53 granted patents. Bureau Veritas Re-Audit PASS, November 2025.
Entendiendo los desafíos de los deshumidificadores LGR
1.1 El flujo de trabajo en restauración de daños por agua
Water damage restoration — from floods, pipe bursts, hurricanes, and HVAC failures — follows a time-critical 4-phase protocol that determines both project outcomes and insurer liability:
- Phase 1: Assessment (0–4 hours) — Moisture mapping, category classification (Cat 1–3), scope documentation
- Phase 2: Water Extraction (4–24 hours) — Submersible pumps, truck-mounted extractors, wet vacuums
- Phase 3: Dehumidification (24–120 hours) — LGR dehumidifiers, air movers, drying chambers (critical phase)
- Phase 4: Verification & Monitoring — Moisture readings, documentation, handoff
During Phase 3, LGR (Low-Grain Refrigerant) dehumidifiers must remove moisture to below 40% RH within 72–96 hours while operating continuously in contaminated environments. A single LGR unit typically moves 250–700 CFM depending on model — and that airflow must be maintained throughout the drying cycle.
1.2 Por qué la filtración de aire es clave en la deshumidificación
Post-water-damage environments contain elevated concentrations of airborne particulates that standard residential HVAC systems are not designed to handle:
Without effective filtration, dehumidifiers operating in these environments suffer compressor contamination leading to equipment failure; coil fouling causing 30–40% efficiency loss; cross-contamination and health hazards for restoration personnel; and frequent breakdowns that extend project timelines and increase insurer costs.
1.3 Limitaciones de los filtros tradicionales
Restoration professionals have historically attempted to use standard HVAC filters in LGR dehumidifiers — with predictable results. Each common filter type fails in a specific way:
| Filter Type | Initial Pressure Drop | 500-hr Pressure Drop | CFM at 500 hrs | Particle Capture |
|---|---|---|---|---|
| HAF Electrostatic (Deli) | 0.15–0.20 in. w.c. | 0.18–0.25 in. w.c. | >85% of rated | 65–92% (0.3–10 μm) |
| MERV 13 Pleated | 0.35–0.50 in. w.c. | 0.80–1.20 in. w.c. | ~52% of rated | 85–95% |
| MERV 8 Pleated | 0.18–0.30 in. w.c. | 0.40–0.65 in. w.c. | ~70% of rated | 40–70% |
| Basic Foam | 0.08–0.15 in. w.c. | 0.25–0.50 in. w.c. | ~78% of rated | <25% (no electrostatic) |
| Fiberglass Panel | 0.04–0.08 in. w.c. | 0.20–0.45 in. w.c. | ~80% of rated | <15% (coarse only) |
Key Insight: A MERV 13 filter starts with acceptable efficiency but reaches unacceptable pressure drop within 200–300 hours — exactly the range when a restoration project is in its critical drying phase. HAF maintains rated airflow across the entire service life.
Explicación de la tecnología HAF
2.1 ¿Qué es el "High Air Flow"?
HAF (High Air Flow) is a designation for filter media engineered through three structural principles that together maintain rated CFM throughout the filter's service life:
- Open Channel Architecture: 60–70% void space (compared to 40% in standard pleated filters) allows dust to load progressively without causing rapid surface blockage.
- Gradient Density Structure: Coarse fibers at the inlet face capture large particles (>10 μm); progressively finer fibers toward the outlet capture smaller particles without concentrating the dust load on one surface.
- Low Initial Pressure Drop: 0.15–0.25 inches w.c. at 500 FPM face velocity, compared to 0.40–0.60 inches for MERV 13 — giving the filter a performance advantage that persists even as it loads with dust.
2.2 Mecanismo de captura electrostática
HAF filter media is electrostatically charged during manufacturing via corona discharge — a high-voltage process that permanently aligns electrical dipoles within the polypropylene/polyester fiber matrix. This charge creates a secondary capture mechanism that is entirely separate from mechanical filtration:
| Capture Mechanism | How It Works | Particle Size Range | Effectiveness |
|---|---|---|---|
| Electrostatic (coulombic) | Charged fiber attracts oppositely-charged particles | 0.3–3.0 μm | High |
| Inertial impaction | Large particles cannot follow airstream curves | >5 μm | High |
| Interception | Particle contacts fiber while following streamline | 1–5 μm | Medium |
| Diffusion (Brownian) | Random particle motion causes contact | <0.3 μm | Low (not HAF's design target) |
⚠️ Critical: Water exposure neutralizes the electrostatic charge permanently. A washed HAF filter loses 60–80% of its particle capture efficiency in the <3 μm range. HAF filters must never be washed or subjected to liquid cleaning.
2.3 Ciencia de materiales: el medio microestructurado
Deli HAF filters use a polypropylene (PP) / polyester (PET) blend optimized for the specific demands of LGR dehumidifier environments:
Especificaciones de los materiales de filtrado
Manufacturing follows a 4-stage process: (1) Meltblown extrusion creates the fine-diameter fiber matrix; (2) Corona discharge charging adds the electrostatic capture mechanism; (3) Antimicrobial treatment is applied to the fiber surface; (4) Multi-layer compression optimizes the density gradient from inlet to outlet face.
2.4 Tratamiento de superficie antimicrobiano
All Deli HAF filters incorporate an antimicrobial surface treatment applied during manufacturing. In water damage restoration environments — where mold spore concentrations can reach 2,500 μg/m³ — a filter without antimicrobial protection can itself become a source of microbial growth and odor within 48–72 hours of continuous operation.
| Test Standard | Organism Tested | Result | Status |
|---|---|---|---|
| ASTM G21 | Mold (Aspergillus, Penicillium) | No growth after 28 days | PASS |
| ISO 846 | Bacteria (E. coli, S. aureus) | >99.9% inhibition | PASS |
| Service Life | All organisms | Effective for filter service life (500–700 hours) | CERTIFIED |
| Safety | VOC emissions | Non-detectable — no VOC off-gassing | COMPLIANT |
Ventajas de rendimiento
3.1 Retención del flujo de aire ante la carga de polvo
The most critical performance differentiator for LGR applications is airflow maintenance under progressive dust loading. The following data reflects ASHRAE 52.2 test methodology at 500 FPM face velocity:
Airflow Retention (% of Initial CFM) vs. Operating Hours
Test Condition: 500 FPM | ASHRAE 52.2 | Synthetic Dust Load
100% ┤━━━━━━━━ Deli HAF Electrostatic ━━━━━━━━━━━━━━━━━━━━━━━━ 87%
│
90% ┤
│╲
80% ┤ ╲━━━━━━ MERV 11 Pleated ━━━━╲
│ ╲
70% ┤ ╲━━━━━━━━━━╲
│ ╲
60% ┤ ╲
│ ╲
52% ┤ ━━━━━━━━
│╲
45% ┤ ╲━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ MERV 13 ━━
└────┴────┴────┴────┴────┴────┴────┴────┴────┴────
0 100 200 300 400 500 600 700 800 900 1000
Operating Hours
Operational Impact: At 500 hours, HAF maintains 87% airflow vs. 52% for MERV 11 and 45% for MERV 13. In a restoration context, this translates to approximately 22% faster structural drying — directly reducing project duration and labor cost.
3.2 Eficiencia de captura de partículas (MERV 8–11)
HAF is not a high-efficiency filter across all particle sizes — it is optimally designed for the 1.0–10 μm range, which covers the primary biological and construction contaminants found in water damage environments:
| Particle Size | HAF (Deli) | MERV 13 Pleated | Foam Filter | Typical Contaminant |
|---|---|---|---|---|
| 0.3–1.0 μm | 55–65% | 80–90% | <10% | Bacteria, smoke |
| 1.0–3.0 μm | 70–80% | 85–95% | 15–25% | Mold spores, fine dust |
| 3.0–10.0 μm | 85–92% | >95% | 40–60% | Mold, drywall, pollen |
| >10.0 μm | >95% | >98% | 80–90% | Coarse dust, hair |
The trade-off is intentional and engineered: HAF sacrifices approximately 15–25% efficiency in the sub-micron range (<1 μm) to achieve the open-channel structure that maintains airflow. For LGR dehumidification — where rated CFM is the primary performance driver — this is the correct engineering trade-off. HEPA-equivalent filtration at LGR airflow volumes would collapse a dehumidifier's moisture removal rate within 50–100 hours of operation.
3.3 Ahorro en costes energéticos
Lower pressure drop translates directly to reduced motor power consumption. The calculation below uses a standard LGR 700-class dehumidifier (1.5 HP fan motor):
Scenario A — Standard MERV 13 Pleated
Scenario B — Deli HAF Electrostatic
3.4 Vida útil del filtro y análisis de TCO
A 3-year total cost of ownership (TCO) analysis per dehumidifier unit, factoring filter cost, labor for replacement, and energy differential:
| Cost Item | HAF (Deli) | MERV 13 Pleated | Basic Foam |
|---|---|---|---|
| Filter unit cost (direct) | $18–25 | $15–22 | $5–8 |
| Replacements per year | 2× (every 250 hrs) | 4× (every 125 hrs) | 6× (every 80 hrs) |
| 3-year filter cost | $108–150 | $180–264 | $90–144 |
| Replacement labor (3 yr) | $80 (6 changes) | $160 (12 changes) | $240 (18 changes) |
| Energy cost differential (3 yr) | Baseline | +$36 | +$60 (higher drop loaded) |
| Equipment downtime risk | Low | Medium (coil fouling) | High (no micro-capture) |
| 3-Year TCO (midpoint) | $317 | $438 | $534 |
| Savings vs. MERV 13 | $121 per unit | — | — |
Guía de aplicación
4.1 Equipos compatibles
Deli HAF filters are manufactured to OEM-equivalent dimensions for all major LGR dehumidifier brands:
| Equipment Brand | Models | Deli Filter SKU | Filter Dimensions |
|---|---|---|---|
| Dri-Eaz | LGR 700, LGR 2800i, LGR 3500i | DL-HAF-DRIEAZ700 | Custom to model spec |
| Phoenix | R200S, R200C, Triumph | DL-HAF-PHX200S | Custom to model spec |
| AlorAir | Storm SLGR 1600X, Sentinel HD55 | DL-HAF-ALOAIR160 | Custom to model spec |
| Dri-Eaz | Phoenix LGR (LGR 2000) | DL-HAF-PHXLGR | Custom to model spec |
| Dri-Eaz | Dri-Pod, F203 | DL-HAF-DRIPOD | Custom to model spec |
| Custom | Non-standard dimensions | DL-HAF-CUSTOM | OEM spec — contact us |
4.2 Mejores prácticas de instalación
- Pre-installation inspection: Confirm filter dimensions match housing spec to ±1 mm. An improperly sized filter allows bypass airflow around the edges, reducing effective capture efficiency by 30–60%.
- Housing inspection: Clean the filter housing with a dry cloth or compressed air before installing a new filter. Mineral deposits or debris in the housing can damage the filter media on installation.
- Orientation: HAF filters have a defined airflow direction — the coarser face (slightly rougher texture) faces the incoming airstream (toward the fan intake). Reversed installation reduces efficiency by approximately 20%.
- Sealing: Ensure the filter seats flush against all four housing edges. Light finger pressure around the perimeter confirms the seal. Do not force or compress the filter — this compresses the open channels and increases pressure drop.
- Initial operation check: After installing a new filter, run the unit for 5 minutes and check for airflow reduction. A properly installed HAF filter should produce no noticeable airflow reduction compared to an unfiltered unit.
4.3 Protocolo de mantenimiento: por qué NO lavar
The most common field error with HAF filters is attempting to wash and reuse them. This is categorically different from humidifier wick filters (which can be lightly rinsed) — HAF filters must not be washed under any circumstances.
⚠️ Why washing permanently damages HAF filters:
The electrostatic charge that enables particle capture in the 0.3–3 μm range is held by aligned electrical dipoles in the polypropylene fiber. Water — especially with any dissolved minerals, detergent, or surfactant — permanently disrupts these dipoles. A washed HAF filter may look cleaner but has lost its primary capture mechanism for the most critical particle size range (mold spores, bacteria). Testing shows 60–80% reduction in sub-3 μm capture efficiency after a single washing.
Correct field protocol when a filter appears heavily loaded:
- Remove filter from housing
- Tap gently against a solid surface 2–3 times to dislodge loose surface debris (outside only)
- Inspect for structural integrity — if media is torn, compressed, or deformed, replace immediately
- If airflow from the unit has not recovered (<85% of baseline), replace the filter
- Never use compressed air directly into the filter face — this embeds debris deeper into the media
Especificaciones del filtro HAF Deli
5.1 Ficha técnica
Filtro HAF estándar — Ficha técnica (TDS-HAF-2026)
5.2 Resultados de pruebas y certificaciones
| Certification / Test | Standard | Result | Certificate Holder |
|---|---|---|---|
| Quality Management System | ISO 9001:2015 | Certified since 2005 | Nantong Deli |
| Environmental Management | ISO 14001:2015 | Certified | Nantong Deli |
| Factory Audit — Manufacturing | Bureau Veritas | Re-Audit PASS (Nov 2025) | MIC-ASR2541690 |
| Mold Resistance | ASTM G21 | No growth / 28 days | On file |
| Bacterial Inhibition | ISO 846 | >99.9% inhibition | On file |
| Hazardous Substance | RoHS / REACH | Compliant | Nantong Deli |
| MEI Award 2025 | Made Excellence Innovation | Winner — Industrial Equipment | meiawards.com |
5.3 Opciones de personalización
All Deli HAF filters are available in custom configurations for OEM and private-label buyers:
- Custom dimensions: Any length × width × thickness within manufacturing capability (contact for feasibility). Dimensional tolerance ±0.5–1.0 mm.
- Media density: Multiple density grades available — select lighter media for maximum airflow (MERV 8 equiv.) or denser media for higher efficiency (MERV 11 equiv.)
- Frame material: Standard cardboard frame; aluminum frame available for high-humidity environments; frameless roll stock for custom integration
- Private label: Custom printing on frame/packaging; your brand name and part numbers
- Bulk packaging: Individual poly bags, multi-pack retail boxes, or bulk carton
Casos de estudio
Operación de limpieza tras huracán — Florida, EE. UU.
Situation: A regional restoration company deployed 32 Dri-Eaz LGR 700 units following a Category 2 hurricane event affecting 14 residential and 3 commercial properties. Previous seasons had used MERV 8 pleated filters, resulting in multiple compressor failures mid-project.
Solution: Switched fleet to Deli HAF DL-HAF-DRIEAZ700 filters. Replacement schedule maintained at 250 operating hours per filter (vs. previous 80-hour schedule with foam filters).
Results (8-week operation):
Daños por agua en edificios comerciales — Reino Unido
Situation: A 3,200 m² commercial office building suffered a burst pipe affecting 4 floors. The restoration contractor used 18 Phoenix R200S units and initially attempted MERV 13 filters to meet indoor air quality documentation requirements. Within 96 hours, 6 units showed significantly reduced airflow output.
Solution: Switched to Deli HAF DL-HAF-PHX200S at the 96-hour mark. Deli provided material data sheets satisfying the contractor's insurer documentation requirement for antimicrobial treatment and particle capture range.
Results:
Resumen de datos de pruebas comparativas
| Parameter | HAF (Deli) | MERV 13 | MERV 8 | Foam | Test Standard |
|---|---|---|---|---|---|
| Initial ΔP (in. w.c.) | 0.08–0.15 | 0.35–0.50 | 0.18–0.30 | 0.05–0.12 | ASHRAE 52.2 |
| ΔP at 500 hrs | 0.18–0.25 | 0.80–1.20 | 0.40–0.65 | 0.25–0.50 | ASHRAE 52.2 |
| CFM retention @ 500 hrs | >85% | ~45% | ~70% | ~78% | Calculated |
| Efficiency 1–3 μm | 70–80% | 85–95% | 50–65% | 15–25% | ASHRAE 52.2 |
| Efficiency 3–10 μm | 85–92% | >95% | 70–80% | 40–60% | ASHRAE 52.2 |
| Antimicrobial | Standard | Optional | Optional | None | ASTM G21 |
| Washable? | No | No | Some | Yes | — |
| Typical service life | 500–700 hrs | 200–300 hrs | 300–400 hrs | 80–120 hrs | Field data |
Glosario de términos
CFM: Cubic Feet per Minute — volume of air moved by a fan or dehumidifier per unit time. LGR dehumidifiers typically operate at 250–700 CFM depending on model size.
Corona Discharge: High-voltage electrical process used during HAF filter manufacturing to permanently charge polypropylene fibers, enabling electrostatic particle capture.
FPM: Feet per Minute — face velocity of air through a filter. Test standard 500 FPM is used in ASHRAE 52.2 filter efficiency testing.
HAF: High Air Flow — filter media designation for electrostatic open-channel filters engineered to maintain rated CFM throughout service life.
LGR: Low-Grain Refrigerant — dehumidifier technology that pre-cools incoming air to remove additional moisture before it reaches the evaporator coil. LGR units deliver higher pints-per-day output than conventional refrigerant dehumidifiers.
MERV: Minimum Efficiency Reporting Value — ASHRAE standard 52.2 filter efficiency rating scale from 1 to 16. Higher MERV = finer particle capture but higher pressure drop.
Pressure Drop (ΔP): Reduction in air pressure across a filter caused by flow resistance. Measured in inches of water column (in. w.c.) or Pascals. Higher ΔP = more motor work required to maintain airflow.
TCO: Total Cost of Ownership — lifecycle cost analysis including product cost, labor, energy, and downtime over a defined period.
Información de contacto y pedidos
Nantong Deli Purification Equipment Co., Ltd.
Nantong, Jiangsu Province, China
Website: ntdeli.top/haf-dehumidifier-filter
Email: amanda@ntdeli.top
WhatsApp: +86 138 6296 0263
MOQ: 300–500 units (standard) | Custom dimensions negotiable
Sample Lead Time: 7 business days
Production Lead Time: 15–30 days after order confirmation
To request a quote or technical consultation:
Send your dehumidifier model number and annual volume to amanda@ntdeli.top. Include "HAF White Paper Inquiry" in the subject line for priority routing. Full technical data sheets, material safety data sheets, ISO certificates, and Bureau Veritas audit report (MIC-ASR2541690) available upon request.