Dantherm DH65 Wall-Mounted Swimming Pool Dehumidifier with Defrost + 7.5kW LPHW Air Heating 💧🔥

Professional Pool Environment Control with Powerful Integrated Heating

The Dantherm DH65AX/L is a high-performance wall-mounted dehumidifier specifically engineered for swimming pool environments, combining powerful moisture extraction with substantial air heating capability. This professional-grade unit removes up to 50 litres of moisture per day while delivering 7.5kW of LPHW air heating, eliminating the need for separate fan heaters or radiators in your pool hall.

With its larger LPHW air heating capacity than previous models and a comparative physical size requiring minimal pipework adjustments, the DH65 offers exceptional versatility and upgrade potential. The corrosion-resistant aluminium housing and fully coated coils ensure long-term reliability in the demanding, high-humidity environment of indoor swimming pools.

🎯 Why Choose the Dantherm DH65?

✅ Dual-Function System – Dehumidifies AND heats your pool room with one compact unit
✅ High Capacity – Removes 2.0 litres per hour (50L/day) of moisture efficiently
✅ Powerful Heating – 7.5kW LPHW heating capacity eliminates need for separate heaters
✅ Total Heat Output – 11.7kW combined heat recovery + LPHW heating
✅ Corrosion Protection – Fully anti-corrosion coated coils for extended lifespan
✅ Flexible Operation – Two fan modes (Cycle and Continuous) for optimized performance
✅ Modern Refrigerant – R454C low-GWP refrigerant for environmental responsibility

🏊 Ideal Applications & Pool Room Sizing

Perfect For:

• Domestic Swimming Pools (6m x 3m to 10m x 5m)
• Therapy Pools requiring precise humidity control
• Hotel & Spa Pools with high occupancy
• Health Club Facilities with extended operating hours
• School Swimming Pools with varying usage patterns

Coverage Capacity

The DH65 is ideally suited for pool rooms between 80-120 m² with ceiling heights of 2.5-3.5m. The 800 m³/hr airflow ensures efficient air circulation and consistent humidity control throughout the space.

Pool Water Surface Area Guide:

• Small domestic pools: 15-25 m²
• Medium domestic/small commercial: 25-40 m²
• Larger domestic/therapy pools: 40-55 m²

⚙️ Complete Technical Specifications

Specification	DH65AX/L (with LPHW Heating)
Dehumidification Performance
Moisture Removal Rate	2.0 litres/hour
Daily Capacity (24hr)	50 litres/day
Heating Performance
Heat Recovery (Dehumidifier Only)	3.3 kW
LPHW Air Heating Output	7.5 kW
Total Combined Heat Output	11.7 kW
Air Handling
Air Flow Rate	800 m³/hr
Fan Operating Modes	2 (Cycle & Continuous)
Noise Level @ 3m	47 dB(A)
LPHW Heating System
LPHW Flow Rate	11.7 litres/min
LPHW Pressure Drop	1.8 m head
Required Water Temperature	80°C
Motorised Valve Connection	Required (supplied by others)
Included Components	1x separate air stat*
Electrical
Power Supply	230V / 50Hz
Fuse Rating (Motor Rated)	13 Amp
Nominal Running Current	4.9 Amp
Full Load Amps (FLA)	5.8 Amp
Power Consumption (Nominal)	1.08 kW
Compressor LRA	21.6 Amp
Control & Operation
Humidistat Type	Electronic
Humidity Range	40% to 80% RH (adjustable)
Defrost System	Standard (operates down to 5°C)
Refrigerant	R454C (low GWP)
Physical Specifications
Housing Material	Aluminium with corrosion resistant coating
Coil Protection	Fully anti-corrosion coated
Wall Mount Dimensions (W x H x D)	1306 x 720 x 265 mm
Condensate Drain Connection	16 mm
LPHW Pipework Connections	Dual position options

*Air stat must be connected to motorised valve (valve and transformer supplied by others)

📋 Technical Documentation & Resources

📄 Dantherm Swimming Pool Dehumidifiers – Complete Range Brochure (opens in new tab)
Comprehensive 8-page technical brochure covering the entire Dantherm dehumidifier range. Includes detailed specifications for DH35, DH65, DH75, DH110, and DH120 models, installation dimensions, performance data at various conditions, wiring diagrams, and mounting guidance. Essential reading for installers and specifiers.

🔑 Key Features & Benefits

🛡️ Superior Corrosion Protection

Aluminium housing with specialized corrosion-resistant coating protects against the harsh, chlorinated pool environment. Fully anti-corrosion coated coils ensure long-term reliability and maintain efficiency throughout the unit’s operational life.

🌡️ Integrated LPHW Air Heating

Factory-fitted 7.5kW low-pressure hot water heating coils provide substantial air warming capacity, eliminating the need for separate radiators or fan heaters. This integrated approach saves space, reduces installation complexity, and provides more efficient heat distribution.

🎛️ Precision Humidity Control

The electronic humidistat offers precise adjustment from 40% to 80% RH, allowing you to maintain optimal comfort levels while protecting your building structure from moisture damage.

❄️ Defrost System as Standard

Built-in defrost capability enables year-round operation in cooler conditions, functioning reliably down to 5°C ambient temperature – essential for pools in unheated or semi-heated buildings.

🔄 Flexible Fan Operation

Two distinct operating modes provide versatility:

• Cycle Mode: Intermittent operation for energy efficiency during low-demand periods
• Continuous Mode: Constant airflow for maximum dehumidification during peak usage

🔧 Easy Installation & Maintenance

Dual-position LPHW pipework connections offer installation flexibility to suit various pool room layouts. Compact wall-mounted design saves valuable floor space while providing optimal air circulation positioning.

🌍 Environmentally Responsible

Utilizes R454C refrigerant – a low global warming potential (GWP) alternative that meets current environmental regulations while delivering excellent performance.

💰 Real-World Performance & Operating Costs

Energy Efficiency Analysis

Dehumidifier Power Consumption: 1.08 kW nominal
Heat Recovery Output: 3.3 kW (free heat from moisture extraction)
Additional LPHW Heat: 7.5 kW (when heating mode active)

Coefficient of Performance (COP): Approximately 3.1
For every 1 kW of electricity used, the dehumidifier recovers 3.1 kW of heat energy

Estimated Running Costs

Operating Mode	Daily Usage	Daily Cost	Monthly Cost
Dehumidification Only (8 hrs/day)	8.6 kWh	£2.15*	£64.50
Dehumidification Only (12 hrs/day)	13.0 kWh	£3.25*	£97.50
With LPHW Heating (8 hrs/day)	8.6 kWh**	£2.15*	£64.50
With LPHW Heating (12 hrs/day)	13.0 kWh**	£3.25*	£97.50

*Based on £0.25/kWh electricity rate (November 2025 average)
**Dehumidifier electrical consumption only; LPHW heating powered by existing boiler

💡 Cost Comparison: Running the DH65 with LPHW heating is significantly more economical than electric resistance heating alternatives, which can cost 2-3x more to operate for equivalent heat output.

⏱️ Dehumidification Performance Estimates

Moisture Removal Timeframes

Based on the DH65’s 2.0 litres/hour extraction rate under standard conditions (30°C air temperature, 60% RH, 28°C pool water):

Pool Room Size	Excess Moisture	Time to Target RH
Small (60 m³)	5 litres	2.5 hours
Medium (90 m³)	8 litres	4 hours
Large (120 m³)	12 litres	6 hours
Extra Large (150 m³)	15 litres	7.5 hours

⚠️ Important Notes:

• Times shown are estimates for reducing humidity from 70% to 60% RH
• Actual performance varies with air temperature, pool water temperature, room ventilation, and occupancy
• Performance figures based on pool water at 28°C, air at 30°C, 60% RH
• Cooler conditions or higher humidity levels will require longer operating times
• Continuous pool use, higher bather loads, and inadequate pool covers will increase moisture generation

🔊 Noise Performance

At just 47 dB(A) measured at 3 metres, the DH65 operates quietly – comparable to:

• Quiet library or bedroom at night (40 dB)
• Moderate rainfall (50 dB)
• Normal conversation at 1m distance (60 dB)

This low noise profile makes it ideal for residential installations and hospitality environments where guest comfort is paramount.

🔌 Installation Requirements

Electrical Installation

• Supply: 230V, 50Hz, single phase
• Fuse: 13 Amp motor-rated fuse required
• Wiring: Suitable for nominal 4.9A running current
• Circuit Protection: Must account for 21.6A compressor LRA (locked rotor amps)

LPHW Heating Connection

✅ Required boiler/heating system water temperature: 80°C
✅ Flow rate requirement: 11.7 litres/min
✅ System pressure drop: 1.8 m head
✅ Pipework connections: 22mm or 28mm (dual position options)
✅ Additional components required (supplied by others):

• Motorised valve for LPHW control
• Low voltage transformer
• Connection to air stat (included with unit)

Physical Installation

• Wall mounting: Suitable wall fixings for 1306mm wide unit required
• Mounting height: Typically 2-2.5m above floor level for optimal air circulation
• Clearances: Minimum 300mm above and below unit, 200mm each side
• Condensate drainage: 16mm drain connection to nearby waste pipe (gravity drain)

Space Requirements

• Wall space required: 1306mm (W) x 720mm (H)
• Protrusion from wall: 265mm depth
• Service access: Allow 500mm clearance in front for maintenance

❓ Frequently Asked Questions

Q: What size swimming pool room is the DH65 suitable for?
A: The DH65 is ideal for pool rooms between 80-120 m² with standard ceiling heights (2.5-3.5m). This typically covers pool water surface areas of 25-55 m², including most domestic pools from 6m x 3m up to 10m x 5m. The 800 m³/hr airflow provides excellent circulation for spaces in this range.

Q: Can I use the DH65 without the LPHW heating function?
A: Yes, the DH65AX model is available without LPHW heating (dehumidification only with heat recovery). However, this listing is specifically for the DH65AX/L model WITH 7.5kW LPHW heating. The heat recovery function (3.3kW) operates on all models as a byproduct of the dehumidification process.

Q: What temperature water do I need for the LPHW heating to work?
A: The LPHW heating system requires a water supply at 80°C to achieve the stated 7.5kW heat output. Lower water temperatures will result in proportionally reduced heating capacity. Your existing boiler/heating system must be capable of delivering water at this temperature.

Q: How much electricity does the DH65 use?
A: The dehumidifier consumes 1.08 kW during nominal operation (4.9 amps). Running 8 hours daily costs approximately £2.15/day or £64.50/month at current energy rates (£0.25/kWh). The LPHW heating is powered by your existing boiler, not electricity, making it highly cost-effective compared to electric heating alternatives.

Q: Is the unit noisy?
A: No. At 47 dB(A) measured at 3 metres, the DH65 is quieter than normal conversation and comparable to light rainfall. It’s suitable for residential installations and quiet commercial environments. The two-speed fan allows you to balance performance with acoustic comfort.

Q: Will it work in cold weather if my pool room isn’t heated?
A: Yes. The DH65 includes a defrost system as standard, allowing operation down to 5°C ambient temperature. This makes it suitable for pools in conservatories, outbuildings, or spaces without constant heating. However, performance is optimized at higher temperatures (see technical specifications).

Q: How often does it need maintenance?
A: Routine maintenance involves cleaning or replacing the air filter every 2-3 months (depending on usage) and annual professional servicing. The corrosion-resistant coatings significantly extend service intervals compared to standard units. Annual servicing should include refrigerant checks, coil inspection, and condensate drain verification.

Q: What’s the difference between this and electric heating models?
A: LPHW (Low Pressure Hot Water) heating uses hot water from your existing boiler, making it far more economical to run than electric resistance heating. Electric models (DH65AX/E) provide 3.5kW of electric heat but cost significantly more to operate. Choose LPHW if you have a boiler system; choose electric if LPHW installation isn’t practical.

Q: Do I need any additional equipment?
A: Yes. The unit includes a separate air stat (thermostat), but you must supply:

• Motorised valve for LPHW control
• Low voltage transformer for the valve
• Suitable electrical wiring and circuit protection
• Condensate drain pipework
• Wall mounting brackets/fixings

Q: Why is humidity control important for swimming pools?
A: Excess humidity causes mould growth, structural damage, corrosion of metal fixtures, discomfort for bathers, and can compromise building integrity over time. Pool water evaporation continuously adds moisture to the air – a typical domestic pool can evaporate 5-10 litres per day. Without proper dehumidification, relative humidity can exceed 80%, leading to condensation, musty odours, and costly damage.

Q: Can this unit be installed in a saltwater pool environment?
A: Yes. The fully anti-corrosion coated coils and corrosion-resistant aluminium housing make the DH65 suitable for saltwater chlorinated pool environments. However, regular maintenance and ensuring adequate ventilation remain important for maximizing lifespan in these more demanding conditions.

Q: What warranty is provided?
A: Dantherm dehumidifiers typically include a 2-year manufacturer’s warranty and are supported by a nationwide network of service engineers. Confirm specific warranty terms with your supplier at time of purchase.

📦 What’s Included

✅ Dantherm DH65AX/L wall-mounted dehumidifier unit
✅ Factory-fitted 7.5kW LPHW heating coil
✅ Electronic humidistat (adjustable 40-80% RH)
✅ 1 x separate air stat (thermostat)
✅ Dual-position LPHW pipework connection options
✅ Defrost system (standard)
✅ Installation and operation manual

❌ Not Included (Supplied by Others):

• Motorised valve for LPHW system
• Low voltage transformer
• Wall mounting brackets and fixings
• Electrical wiring and circuit protection
• Condensate drain pipework
• LPHW pipework and connections

⚠️ Important Installation Notes

🔴 LPHW System Requirements
This unit requires a low-pressure hot water heating system capable of delivering water at 80°C. The stated 7.5kW heat output is only achievable with water at this temperature. Verify your existing heating system compatibility before purchase.

🔴 Electrical Installation
Must be installed by a qualified electrician in accordance with current IEE Wiring Regulations. Motor-rated fuses are required to handle the compressor’s locked rotor amps (LRA) of 21.6A during startup.

🔴 Condensate Drainage
Ensure the 16mm condensate drain has a clear path to a suitable waste pipe. The drain relies on gravity, so the unit must be positioned with adequate fall to the drainage point.

🔴 Performance Conditions
Stated performance figures assume:

• Pool water temperature: 28°C
• Air temperature: 30°C
• Relative humidity: 60% RH
• LPHW supply: 80°C

Performance will vary under different conditions. Colder temperatures, higher humidity, or lower water temperatures will affect dehumidification capacity.

🏆 Why Dantherm?

Dantherm has decades of experience in pool environment control, with dehumidifiers installed in thousands of domestic and commercial swimming pools worldwide. The DH65 represents the latest evolution of their proven technology, offering:

• Proven reliability in harsh pool environments
• Efficient heat recovery technology that converts moisture into useful heat
• Corrosion protection exceeding industry standards
• Compact design that maximizes performance while minimizing space requirements
• Nationwide service network for ongoing support

This is a professional-grade solution for anyone serious about protecting their pool investment and maintaining a comfortable, healthy swimming environment.

🛒 Ready to Improve Your Pool Environment?

The Dantherm DH65 with 7.5kW LPHW heating delivers comprehensive environmental control in one compact, wall-mounted unit. Stop battling condensation, mould, and uncomfortable humidity – invest in professional-grade climate control that protects your building and enhances swimmer comfort.

Technical questions? Our team can help you determine if the DH65 is the right solution for your specific pool room and discuss installation requirements.