💦 Calplas DCH-640 Commercial High-Bed Sand Filter – 2″ Connections

Robust commercial filtration for medium-sized pools demanding exceptional water clarity

🏊 Product Overview

The Calplas DCH-640 is a heavy-duty commercial sand filter engineered for medium-sized swimming pools, wellness facilities, and demanding aquatic installations. With its substantial 640mm diameter tank and 1200mm deep filter bed, this filter delivers outstanding particulate removal and crystal-clear water quality that meets the exacting standards of commercial pool operators.

Built by Calplas, Spain’s premier filter manufacturer with over five decades of expertise since 1970, the DCH-640 features hand-laminated GRP (glass-reinforced polyester) construction with internal steel reinforcement. This industrial-grade build ensures reliable performance under continuous commercial operation. The generous 0.30 m² filter area provides flow rates up to 15.5 m³/h during backwash and 9.3 m³/h for standard filtration.

Perfect for hotel pools, leisure centres, holiday parks, and large residential installations where superior filtration performance and long-term reliability are essential.

🌟 Key Features

✅ Heavy-Duty GRP Construction – Hand lay-up glass-reinforced polyester with internal steel reinforcement for commercial-grade durability

✅ 1200mm Deep Filter Bed – Extended media depth provides superior water polishing and longer filter runs (1500mm available on request)

✅ 0.30 m² Filter Area – Large filtration surface handles higher flow rates and bather loads efficiently

✅ 9.3 m³/h Filtration Flow Rate – Suitable for pools up to 74,000 litres with 8-hour turnover

✅ 2″ Threaded Connections – Female GAS threads moulded directly into the filter body for secure, leak-free plumbing

✅ 355mm Service Manhole – Larger access opening for easier media inspection, maintenance, and replacement

✅ Special AFM/Sand Diffuser – Engineered top diffuser eliminates crater formation and media channelling

✅ Integrated Sight Glass – Large 20mm sight glass for clear backwash monitoring

✅ Temperature Resistant to 40°C – Ideal for heated pools and spa applications (ozone resistance available on request)

✅ Commercial Pressure Rating – 2.5 bar maximum operating pressure with 3.75 bar test pressure

✅ 5 Year Tank Warranty – Comprehensive manufacturer warranty on tank integrity

🔧 Technical Specifications

Specification	Value
Model	DCH-640
Product Code	1519260264 / 212364
Filter Type	High-Bed Sand/AFM Filter
Tank Diameter	640 mm
Tank Height	1886 mm
Filter Area	0.30 m²
Filter Bed Height	1200 mm (1500 mm available on request)
Flow Rate (Filtration @ 30 m³/h/m²)	9.3 m³/h
Flow Rate (Backwash @ 50 m³/h/m²)	15.5 m³/h
Working Pressure	2.5 bar
Test Pressure	3.75 bar
Inlet/Outlet Connection	2″ Female (GAS thread)
Filter Opening (Top)	ø 190 mm
Service Manhole	ø 355 mm
Distance from Ground (A)	338 mm
Distance Between Connections (B)	1229 mm
Tank Material	GRP (Glass-Reinforced Polyester) with steel reinforcement
Weight (Empty)	77 kg
Maximum Temperature	40°C
Colour	Blue RAL 5015 (white available on request)
Certifications	Manufactured according to EN 13121-3
Warranty	5 Years Tank Warranty

📐 Pool Sizing Guide

The Calplas DCH-640 delivers a filtration flow rate of 9.3 m³/h, making it ideal for medium-sized commercial pools and large residential installations.

Sizing Formula:

Pool Capacity = Flow Rate × Turnover Time

Turnover Time	Maximum Pool Capacity	Application
6 hours (optimal)	55,800 litres	Commercial pools, high bather loads
8 hours (standard)	74,400 litres	Private pools, moderate usage

Pool Size Compatibility:

Pool Type	Suitability	Notes
🏠 Large residential in-ground	✅ Excellent	Up to 74,000 L with 8-hour turnover
🏢 Medium commercial pool	✅ Ideal	Up to 55,000 L with 6-hour turnover
🏨 Hotel pools	✅ Excellent	Built for continuous commercial operation
🧖 Spa and wellness centres	✅ Recommended	Superior water clarity for demanding applications
🏊 Leisure centre pools	✅ Ideal	Professional-grade reliability

This Filter:

• 📍 Filtration Flow Rate: 9.3 m³/h
• 📍 Backwash Flow Rate: 15.5 m³/h
• 📍 Optimal for pools up to: 55,800 litres (6-hour turnover)
• 📍 Maximum recommended: 74,400 litres (8-hour turnover)

🔌 Installation Requirements

Plumbing Connections

Requirement	Specification
Inlet Connection	2″ Female (GAS thread)
Outlet Connection	2″ Female (GAS thread)
Connection Position	Side-mounted
Connection Spacing (B)	1229 mm

Physical Installation

Requirement	Details
Base	Solid, level concrete pad required
Clearance Above	Minimum 500 mm for manhole access and valve operation
Clearance Around	Minimum 500 mm for maintenance access
Distance from Ground (A)	338 mm (built-in legs)

Pump Compatibility

⚠️ Important: This filter must be matched with an appropriately sized pump.

Parameter	Specification
Recommended Pump Flow Rate	6 – 9.3 m³/h for filtration
Maximum Pump Flow Rate	Do not exceed 15.5 m³/h
Backwash Requirement	Pump capable of 15.5 m³/h for effective backwashing

💡 Tip: For optimal performance, select a pump that delivers flow rates within the filtration range. Oversized pumps can damage filter media and reduce filtration efficiency.

🧹 Maintenance Guide

Routine Maintenance Schedule

Task	Frequency	Details
Check pressure gauge	Weekly	Note baseline pressure when clean
Backwash filter	When pressure rises 0.5-0.7 bar above baseline	Until sight glass shows clear water
Rinse after backwash	After every backwash	30-60 seconds to settle media
Inspect manhole seal	Seasonally	Replace O-ring if worn or damaged
Check media level	Annually	Top up if settlement occurs
Complete media replacement	Every 5-7 years (sand) / 10+ years (AFM)	Replace entire filter bed

Pressure Gauge Guide

Reading	Status
📊 Baseline (clean filter)	Record this reading after fresh backwash
📊 Backwash needed	0.5-0.7 bar above baseline
📊 Maximum safe pressure	2.5 bar

⚠️ Warning: Never operate the filter above 2.5 bar. If pressure remains elevated after backwashing, investigate for media channelling or consider media replacement.

Winterisation (UK Climate)

For outdoor installations or unheated plant rooms:

1. Fully drain the filter tank via the drain plug
2. Remove and safely store the drain plug
3. Leave multiport valve in the winterise position (if fitted)
4. Cover the filter or relocate to a frost-free environment
5. Never leave water in the filter during freezing conditions

⚠️ Frost damage is not covered under warranty

---

🪨 Filter Media Information

The Calplas DCH-640 accommodates substantial media volumes for effective deep-bed filtration with either traditional sand or advanced AFM® glass media.

Media Requirements (per filter)

Media Type	Layer Configuration	Total Quantity
AFM®	G3: 0 bags / G2: 7 bags / G1: 16 bags	23 bags × 21 kg = 483 kg
Sand	2-3mm: 0 bags / 0.7-1.2mm: 7 bags / 0.4-0.8mm: 16 bags	23 bags × 25 kg = 575 kg

Media Comparison

Media Type	Filtration Rating	Lifespan	Benefits
Sand	20-40 microns	5-7 years	Economical, widely available
Glass (AFM®)	5-15 microns	10+ years	Finer filtration, self-sterilising, longer life
ZeoSand	3-5 microns	5 years	Superior clarity, ammonia reduction

💡 Recommendation: For commercial installations with high bather loads, AFM® glass media provides significantly finer filtration (5-15 microns vs 20-40 microns for sand) and extended service life, reducing long-term operating costs.

Signs Media Needs Replacing

• Poor water clarity despite correct chemical balance
• Short filter cycles between backwashes
• Cloudy water returning to pool after filtration
• Media visible in pool (indicates damaged laterals)
• Increased chemical consumption

---

🔬 Filtration Performance

Metric	Value
Filter Area	0.30 m²
Filter Bed Height	1200 mm
Filtration Rating (Sand)	20-40 microns
Filtration Rating (AFM®)	5-15 microns

Micron Rating Guide

Rating	What It Captures
40+ microns	Visible debris, leaves, large particles
20-40 microns	Sand, dirt, visible suspended matter
10-20 microns	Fine particles, some algae spores
5-10 microns	Very fine particles, most algae, bacteria clusters

The 1200mm deep filter bed provides extended contact time between water and media, delivering superior particle capture and water clarity compared to standard-depth residential filters.

---

⚙️ Multiport Valve Functions

Note: Valve sold separately. Compatible with 2″ side-mount multiport valves.

Position	Function
Filter	Normal filtration – water flows through media to pool
Backwash	Reverses flow to flush debris from media to waste
Rinse	Settles media and clears pipework after backwash
Waste	Bypasses filter, sends water directly to drain
Recirculate	Bypasses filter, returns water to pool (for chemical distribution)
Closed	Stops all water flow
Winterise	Relieves pressure from all ports for winter storage

---

🎯 Ideal Applications

Application	Pool Size	Suitability
🏠 Large residential in-ground	Up to 74,000 L	✅ Excellent for demanding homeowners
🏢 Medium commercial pools	Up to 55,000 L	✅ Designed for commercial duty
🏨 Hotel and resort pools	Up to 55,000 L	✅ Built for continuous operation
🧖 Spa and wellness facilities	Various	✅ Superior water clarity
🏫 School and leisure centre pools	Up to 55,000 L	✅ Professional reliability
🏊 Hydrotherapy and rehabilitation pools	Up to 55,000 L	✅ High-quality filtration essential

❓ Frequently Asked Questions

Q: What size pool will this filter handle? A: The DCH-640 is suitable for pools up to 55,800 litres with optimal 6-hour turnover, or up to 74,400 litres with 8-hour turnover. The 9.3 m³/h filtration flow rate provides professional-grade water treatment for medium commercial installations.

Q: How often do I need to backwash? A: Backwash when the pressure gauge reads 0.5-0.7 bar above your clean baseline reading, typically every 1-2 weeks depending on bather load and environmental factors. Always rinse for 30-60 seconds after backwashing.

Q: What filter media should I use? A: The filter is compatible with both sand and AFM® glass media. For commercial installations, we strongly recommend AFM® for its finer filtration (5-15 microns vs 20-40 microns for sand) and extended 10+ year lifespan.

Q: How much filter media do I need? A: For sand: approximately 575 kg in layered grades (23 bags × 25 kg). For AFM®: approximately 483 kg (23 bags × 21 kg). Contact Parts4Tubs for specific filling plans.

Q: What pump do I need? A: Match with a pump delivering 6-9.3 m³/h for filtration. The pump must be capable of 15.5 m³/h for effective backwashing. Never exceed the filter’s maximum flow rate.

Q: Is a multiport valve included? A: No, the backwash valve/front tube system is sold separately. The filter accepts 2″ side-mount multiport valves. Automatic and manual options are available.

Q: What is the delivery time? A: Calplas DCH filters are hand-made to order in Spain. Please allow 4-6 weeks delivery time. Contact Parts4Tubs for current lead times.

Q: What warranty is included? A: This filter comes with a 5 Year Tank Warranty from Calplas. Contact Parts4Tubs for full warranty terms and conditions.

Q: Can this filter handle heated pools? A: Yes, the DCH-640 is temperature resistant up to 40°C, making it suitable for heated swimming pools and spa installations. Ozone resistance is available on request for additional applications.

Q: How does this compare to the DCH-520? A: The DCH-640 offers 50% more filter area (0.30 m² vs 0.20 m²) and 55% higher flow rates, making it suitable for pools approximately 50% larger than the DCH-520.

📥 Downloads & Resources

📄 Calplas DCH Filter Datasheet – Complete specifications and dimensions

⭐ Why Choose the Calplas DCH-640

✅ Commercial-Grade Construction – Hand lay-up GRP with internal steel reinforcement engineered for demanding commercial environments

✅ Generous Filter Area – 0.30 m² provides excellent flow capacity and extended filter runs between backwashes

✅ Superior Filtration Depth – 1200mm filter bed height delivers exceptional water polishing unmatched by standard filters

✅ World-Renowned Manufacturer – Calplas has produced premium filters since 1970 with proven reliability in installations worldwide

✅ Larger Service Access – 355mm manhole simplifies media inspection and maintenance

✅ 5 Year Tank Warranty – Comprehensive warranty coverage demonstrates manufacturer confidence in build quality

✅ Versatile Media Options – Compatible with sand, AFM®, or zeolite for flexibility in filtration performance

🤝 Why Buy from Parts4Tubs

✅ UK-Based Company – Local support from pool and spa specialists

✅ Fast UK Delivery – Efficient shipping across the United Kingdom

✅ Expert Technical Advice – Our team can help with sizing, installation, and media selection

✅ Competitive Pricing – Trade and retail pricing on commercial equipment

✅ Full Warranty Support – We handle warranty claims directly with manufacturers

✅ Easy Returns – 30-day return policy on unused items

✅ Complete System Supply – Pumps, valves, media, and accessories all available

💧 Summary

The Calplas DCH-640 Commercial High-Bed Sand Filter delivers robust, professional-grade filtration for pools up to 74,000 litres. With its 640mm diameter tank, 0.30 m² filter area, and 1200mm deep filter bed, this hand-crafted filter provides exceptional water clarity for medium-sized commercial pools, hotel installations, and demanding residential applications. The 9.3 m³/h flow rate, commercial pressure rating, and 5 Year Tank Warranty make it a reliable investment for installations where consistent water quality is paramount.