💨 DH110AX | Monitair 110 Swimming Pool Dehumidifier with Defrost – Single Phase

Protect Your Indoor Pool Investment with Professional-Grade Moisture Control

The Monitair 110 (DH110AX) is a powerful, energy-efficient dehumidifier specifically engineered for indoor swimming pool environments. Whether you manage a domestic pool, therapy center, health club, hotel spa, or leisure facility, this sophisticated unit delivers reliable moisture control that protects your building structure while creating a comfortable, healthy swimming environment.

Key Benefits at a Glance:

✅ 108 litres per day dehumidification capacity – handles even the most demanding pool environments
✅ Energy recovery technology – converts moisture energy into 6.4 kW of free heat
✅ Advanced defrost system – operates reliably down to 5°C for year-round performance
✅ Flexible installation – available as wall mount or through-wall (TTW) configuration
✅ Optional LPHW air heating – adds 8.9 kW heating capacity for complete climate control
✅ Single-phase operation – straightforward electrical installation
✅ 2-year manufacturer warranty – backed by nationwide service network

Why Your Indoor Pool Needs the Monitair 110

Indoor swimming pools create unique environmental challenges. Every hour, thousands of litres of water evaporate into the air, creating moisture levels that – if left unchecked – cause devastating structural damage, corrosion, mold growth, and an uncomfortable environment for swimmers.

The Monitair 110 solves these problems by:

Preventing Structural Damage – Continuous moisture control prevents corrosion of metal fixtures, degradation of building materials, and expensive repair bills down the line.

Creating Comfortable Conditions – Maintains optimal humidity levels (typically 60-65% RH) so swimmers feel warm when they exit the pool, and the air doesn’t feel heavy or clammy.

Recovering Free Energy – Unlike ventilation systems that throw away heat, the Monitair 110 captures the latent energy locked in water vapor and returns it to your pool hall as useful heat. This reduces boiler running time and energy costs.

Protecting Health – Proper humidity control inhibits mold, bacteria, and allergen growth, creating a healthier environment for swimmers and staff.

How the Monitair 110 Works

The Monitair 110 uses advanced heat pump technology to remove moisture from pool hall air while simultaneously recovering heat:

1. Moisture-laden warm air is drawn into the unit from your pool hall
2. The air passes over a cold evaporator coil where moisture condenses into water
3. This water is drained away through a 15mm condensate drain
4. The dried air is then reheated using the recovered energy from the condensation process
5. Warm, dry air is returned to the pool hall at approximately 6.4 kW heating capacity
6. Optional LPHW (Low Pressure Hot Water) heating can add an additional 8.9 kW for total heating output of 12.2 kW

This process is exceptionally efficient because it reuses the energy that would otherwise be wasted, making it far more economical than traditional ventilation-based dehumidification.

Technical Specifications

Performance Data

Specification	Value	Notes
Model Number	DH110AX (Standard) / DH110AX/L (with LPHW heating)	Single phase operation
Dehumidification Capacity	4.5 litres/hour	108 litres per day
Heat Recovery to Air	6.4 kW	Free heat from dehumidification
LPHW Heating Output	8.9 kW	Optional – requires boiler connection
Maximum Total Heat Output	12.2 kW	Combined heat recovery + LPHW
Air Flow Rate	1,180 m³/hr	Nominal recirculating air flow
Defrost System	Standard	Operates down to 5°C ambient

Electrical Requirements

Specification	Single Phase (1ph)
Electrical Supply	230V / 50Hz
Nominal Power Consumption	2.12 kW
Nominal Running Current	9.3 Amps
Full Load Amps (FLA)	10.6 Amps
Compressor LRA	66 Amps
Required Fuse	20 Amp (motor-rated)

⚠️ Important: All fuses should be motor-rated for safe operation.

Plumbing Requirements (LPHW Models Only)

Connection	Specification
LPHW Supply/Return	22mm copper stub connections
LPHW Flow Rate	9.6 litres/min
LPHW Pressure Drop	2.8 metres head
Recommended Boiler Output	8.9 kW minimum
Boiler Water Temperature	80°C (typical)
Condensate Drain	15mm diameter

💡 Note: Standard models (DH110AX) do not require plumbing connections. LPHW models (DH110AX/L) include a motorized 3-way valve for heating control.

Physical Dimensions & Weight

Wall Mount Models (DH110AX / DH110AX/L):

Dimension	Measurement
Width	1,520 mm
Height	796 mm
Depth	385 mm
Weight (unpacked)	153 kg

Through-Wall Models (DH110AX/T / DH110AX/TL):

Dimension	Measurement
Width	1,474 mm
Height (to top duct)	1,167 mm
Depth	350 mm
Weight (unpacked)	153 kg

Environmental & Acoustic Data

Specification	Value
Noise Level @ 3m	48.5 dB(A)
Operating Temperature Range	5°C to 35°C (with defrost)
Humidity Control Range	20% to 80% RH (adjustable humidistat)
Refrigerant Type	R407C (ozone-friendly)

Room Coverage & Suitability Guide

The Monitair 110 is designed for medium to large indoor swimming pool installations. Use the guide below to determine if this model suits your application:

Ideal Applications

✅ Domestic Indoor Pools – residential pools up to 10m x 5m
✅ Hotel & Spa Facilities – guest swimming pools and leisure areas
✅ Therapy Centers – hydrotherapy and rehabilitation pools
✅ Health Clubs & Gyms – small commercial swimming facilities
✅ Small Leisure Centers – community pools and teaching pools
✅ Private Swim Schools – indoor training facilities

Pool Hall Volume Recommendations

The Monitair 110 can effectively dehumidify pool halls with volumes up to approximately 600-800 m³, assuming:

• Pool water temperature: 28°C
• Air temperature: 30°C
• Target relative humidity: 60%
• Normal pool usage patterns
• Adequate building insulation and vapor barriers

💡 Calculating Your Pool Hall Volume:
Length (m) × Width (m) × Average Height (m) = Volume (m³)

Example: A pool hall measuring 12m long × 8m wide × 4m high = 384 m³ (suitable for Monitair 110)

⚠️ Larger Facilities: If your pool hall exceeds 800 m³ or you have multiple pools, consider multiple units or larger commercial models.

Estimated Dehumidification Performance

Daily Moisture Removal by Pool Size

These estimates show how much moisture the Monitair 110 can remove based on typical evaporation rates from different pool sizes:

Pool Size	Surface Area	Est. Daily Evaporation*	Monitair 110 Capacity	Suitability
Small (6m × 3m)	18 m²	~40-50 L/day	108 L/day	✅ Excellent
Medium (8m × 4m)	32 m²	~70-80 L/day	108 L/day	✅ Good
Large (10m × 5m)	50 m²	~100-110 L/day	108 L/day	✅ Adequate
Very Large (12m × 6m)	72 m²	~140-160 L/day	108 L/day	⚠️ Consider dual units

*Evaporation estimates based on 28°C pool water, 30°C air temperature, 60% RH, and moderate pool usage. Actual evaporation varies with usage intensity, air movement, and environmental conditions.

Factors Affecting Dehumidification Performance

Increases Moisture Load:

• Higher water temperatures
• More swimmers and activity
• Water features (fountains, slides, spa jets)
• Poor building insulation or air leaks
• No pool cover when not in use

Reduces Moisture Load:

• Using a thermal pool cover when closed
• Lower water temperatures
• Better building vapor barriers
• Proper air distribution
• Regular maintenance

Heat Output & Energy Savings

Understanding Heat Recovery Benefits

The Monitair 110’s heat recovery system captures energy from the dehumidification process, delivering 6.4 kW of “free” heat back into your pool hall. This significantly reduces the workload on your primary heating system.

Annual Energy Cost Comparison*

Heating Method	Typical Running Cost	Savings vs. Ventilation
Monitair 110 Heat Recovery	£1,200 – £1,800/year	Baseline
Ventilation + Electric Heating	£3,500 – £4,500/year	💰 Save £2,000-£2,700
Ventilation + Gas Heating	£2,000 – £2,800/year	💰 Save £800-£1,000

*Estimates based on 8 hours daily operation, average UK energy costs (2024), and a medium-sized pool hall. Actual costs vary with pool size, usage patterns, insulation quality, and energy tariffs.

Heating Performance with LPHW Option

For models equipped with LPHW air heating (DH110AX/L):

• Total heating capacity: 12.2 kW (6.4 kW heat recovery + 8.9 kW LPHW)
• Boiler connection: 22mm copper stub connections
• Boiler water temperature: 80°C optimal
• Built-in motorized 3-way valve: Automatic temperature control
• Thermostat included: Wall-mounted air thermostat for precise control

This dual heating capability often eliminates the need for separate fan heaters or radiators, simplifying your pool hall’s mechanical systems.

Installation Options

The Monitair 110 offers two installation configurations to suit your facility layout:

Option 1: Wall Mount (DH110AX / DH110AX/L)

Best for:

• Pool halls with adequate wall space
• Installations where the unit can be mounted directly in the pool hall
• Facilities where aesthetics and easy access are priorities

Features:

• Smooth white coated alloy finish
• Wall-mounted installation brackets
• Direct discharge into pool hall
• Easy filter access for maintenance
• All-in-one visible installation

Clearance Requirements:

• Minimum 500mm clearance from ceiling
• Minimum 300mm clearance from side walls
• Minimum 1,000mm clearance in front for servicing

Option 2: Through-Wall (DH110AX/T / DH110AX/TL)

Best for:

• Installations where the unit should be hidden in an adjacent plant room
• Facilities with limited pool hall space
• Applications requiring quieter operation in the pool area
• Installations where aesthetics are critical

Features:

• Unit installed in separate plant room
• Decorative supply and intake grilles visible in pool hall
• Duct sleeves and mounting brackets included
• Easier access for maintenance (from plant room)
• Reduced visible equipment in pool hall

Installation Requirements:

• Two wall penetrations required (supply and intake)
• Wall must be sealed to prevent air recirculation
• Cavity walls require non-porous sleeve/board around penetrations
• Grilles supplied for pool hall side
• Plant room access required for servicing

💡 Tip: Through-wall models are ideal for maintaining a clean, uncluttered aesthetic in premium pool halls while keeping mechanical equipment out of sight.

Installation Clearance & Placement Guidelines

Minimum Clearance Requirements (All Models)

Location	Minimum Clearance	Purpose
Above unit	500mm	Heat dissipation & air circulation
Either side	300mm	Service access & air flow
Front of unit	1,000mm	Filter access & maintenance
Below unit	Floor-mounted or secure wall bracket	Condensate drainage access

Optimal Placement Recommendations

✅ DO:

• Position to ensure even air distribution across the pool hall
• Install where return air can be drawn from across the pool surface
• Ensure condensate drain has adequate fall to waste
• Mount securely to structural walls capable of supporting 153 kg
• Provide easy access for filter cleaning and maintenance
• Position away from direct splashing or water spray

❌ AVOID:

• Installing in corners where air circulation is restricted
• Positioning discharge air directly at swimmers
• Mounting where condensation from the unit could drip onto pool deck
• Locations with inadequate drainage for condensate
• Areas with poor access for maintenance
• Direct sunlight on controls or sensors

Electrical Installation Notes

⚠️ Important Electrical Requirements:

• Must be installed by a qualified electrician
• Requires dedicated circuit with 20 Amp motor-rated fuse (single phase)
• Must comply with IEE Wiring Regulations (BS 7671)
• RCD protection recommended
• Suitable cable sizing for 10.6 Amp full load current
• Proper earthing is essential in pool hall environments
• Consider high humidity environment when selecting cable routes and fittings

Maintenance & Filter Care

Regular Maintenance Schedule

Weekly (during high-use periods):

• Visually inspect unit operation
• Check condensate drainage is working
• Listen for unusual noises

Monthly:

• Clean or replace air filters – Most important maintenance task!
• Check humidistat setting
• Verify condensate drain is clear

Quarterly:

• Inspect all electrical connections
• Check refrigerant lines for damage
• Clean external surfaces
• Verify LPHW connections (if fitted)

Annually (Professional Service Recommended):

• Full system inspection by qualified engineer
• Refrigerant pressure check
• Compressor performance verification
• Electrical safety testing
• Deep clean of coils and internals

Filter Maintenance (Critical for Performance)

🔧 Why Filter Maintenance Matters:

Dirty filters are the #1 cause of reduced dehumidification performance. Blocked filters restrict airflow, which:

• Reduces moisture removal capacity
• Increases energy consumption
• Can cause icing on coils
• Leads to compressor damage if neglected

How to Clean Filters:

1. Switch off the unit and isolate from mains power
2. Remove the front grille – usually secured with clips or screws
3. Slide out the washable filters
4. Vacuum off loose dust using a soft brush attachment
5. Wash in warm soapy water – gentle detergent only
6. Rinse thoroughly with clean water
7. Allow to dry completely before reinstalling (typically 2-3 hours)
8. Reinstall filters and grille – ensure secure fit
9. Restore power and verify normal operation

💡 Pro Tip: Keep a spare set of filters so you can swap them out immediately and clean the dirty set at your convenience without downtime.

Control & Operation

Humidistat Control

The Monitair 110 includes an adjustable humidistat that allows you to set your desired humidity level between 20% and 80% RH.

Recommended Settings for Pool Halls:

Application	Recommended RH	Reason
Standard pools	60-65%	Optimal comfort and structural protection
Warmer pools (30°C+)	55-60%	Reduces condensation risk on cold surfaces
Therapy pools	60-65%	Comfortable for extended sessions
Winter operation	55-60%	Compensates for colder external temperatures

💡 Setting Your Humidistat:

• Start at 60% RH and adjust based on comfort and condensation observations
• If condensation appears on windows or cold surfaces, lower the setting by 5%
• If the air feels too dry or swimmers feel cold, increase by 5%
• Allow 24-48 hours for the system to stabilize after changes

LPHW Air Heating Control (DH110AX/L Models)

Models with LPHW heating include:

• Wall-mounted air thermostat (supplied with unit)
• Built-in motorized 3-way valve – automatically controls hot water flow
• Integrated control system – coordinates heating with dehumidification

Operating the Heating Function:

1. Set the air thermostat to your desired pool hall temperature (typically 28-30°C)
2. The unit will automatically call for heat when temperature drops below setpoint
3. The 3-way valve opens to allow hot water through the heating coil
4. When temperature is satisfied, the valve closes and heating stops
5. Dehumidification continues regardless of heating status

Frequently Asked Questions

General Operation Questions

Q: How long does it take for the Monitair 110 to bring high humidity under control?

A: Initial dehumidification of a very humid pool hall typically takes 24-72 hours of continuous operation. Once controlled, the unit maintains desired humidity levels automatically. Factors affecting initial performance include starting humidity levels, pool hall volume, building insulation quality, and outdoor weather conditions.

Q: Can I run the Monitair 110 24/7, or should I turn it off when the pool isn’t in use?

A: For optimal moisture control and building protection, we recommend continuous operation or at minimum, running the unit whenever the pool isn’t covered. Moisture evaporates 24/7, so intermittent operation allows humidity to climb during off-periods, leading to condensation and potential structural damage. Continuous operation is more energy-efficient and provides better results than frequent on/off cycling.

Q: Why is there frost or ice on my dehumidifier?

A: The Monitair 110 includes an automatic defrost system that activates when ice forms on the evaporator coil. This is normal operation in colder conditions (below 15°C ambient). During defrost cycles, the compressor stops while the fan continues to melt accumulated ice. If frost persists or the unit ices up frequently, check:

• Air filters may be dirty (restricting airflow)
• Humidistat may be set too low
• Pool hall temperature may be too cold
• Refrigerant levels may need checking (call service engineer)

Q: What temperature should I maintain in my pool hall?

A: Optimal pool hall air temperature is typically 2-4°C above pool water temperature. For a 28°C pool, aim for 30-32°C air temperature. This prevents swimmers feeling cold when exiting the pool while minimizing evaporation rates. Lower air temperatures increase evaporation and create uncomfortable conditions; higher temperatures waste energy and can feel oppressive.

Installation Questions

Q: Can I install the Monitair 110 myself, or do I need a professional?

A: We strongly recommend professional installation by a qualified HVAC engineer familiar with pool hall dehumidifiers. Installation requires:

• Electrical work by a certified electrician (Part P compliance)
• Plumbing work for LPHW models (if fitted)
• Proper wall mounting or through-wall preparation
• Condensate drainage installation
• Refrigerant system integrity checks
• Commissioning and testing

DIY installation may void your warranty and create safety hazards.

Q: Do I need a wall mount or through-wall model?

A: Choose Wall Mount if:

• You have adequate wall space in your pool hall
• Easy access for maintenance is a priority
• You want a simpler, lower-cost installation
• Your facility doesn’t have an adjacent plant room

Choose Through-Wall if:

• You want to hide the unit in a plant room
• Pool hall aesthetics are critical
• You have limited pool hall space
• You prefer quieter operation in the pool area
• You already have a plant room with access

Q: What size electrical supply do I need?

A: The single-phase Monitair 110 requires:

• 230V / 50Hz supply
• 20 Amp motor-rated fuse or circuit breaker
• Cable rated for 10.6 Amps full load current (minimum 2.5mm² twin + earth)
• RCD protection recommended for added safety

For through-wall installations, ensure the electrical supply is routed to the plant room location. Always consult a qualified electrician.

Performance & Efficiency Questions

Q: How much does it cost to run the Monitair 110?

A: Running costs depend on electricity prices and operating hours, but typical estimates:

• Power consumption: 2.12 kW
• Hours per day: 8-12 hours (average)
• Daily usage: ~17-25 kWh
• Monthly usage: ~510-750 kWh
• Cost @ £0.30/kWh: £150-£225 per month

However, the 6.4 kW of recovered heat significantly reduces your overall heating costs, typically saving £100-200+ monthly compared to ventilation-based dehumidification. The net additional cost is often £50-75/month for superior moisture control.

Q: Will the Monitair 110 heat my pool hall, or do I need separate heaters?

A: Standard models (DH110AX) provide 6.4 kW of heat recovery, which contributes to pool hall heating but is typically insufficient as the sole heat source in winter. You’ll likely need supplementary heating.

LPHW models (DH110AX/L) provide 12.2 kW total heating (6.4 kW heat recovery + 8.9 kW LPHW), which is often sufficient for small to medium pool halls as the primary heating source, potentially eliminating the need for separate heaters or radiators. Consult a pool hall design specialist for accurate heat load calculations.

Q: Does the Monitair 110 bring in fresh air, or just recirculate pool hall air?

A: The Monitair 110 is a recirculating dehumidifier – it does not bring in outside air. It treats and recirculates the existing pool hall air, removing moisture and adding recovered heat.

For fresh air ventilation (recommended for air quality and bather comfort), you’ll need a separate ventilation system such as the INDUX E300 Heat Recovery Ventilator or similar. Most pool halls combine a dehumidifier (like the Monitair 110) with a heat recovery ventilator for optimal climate control.

Q: How often should the Monitair 110 be serviced?

A: We recommend:

• Monthly: User-performed filter cleaning
• Quarterly: Basic inspection (drainage, operation, visual checks)
• Annually: Full professional service by a qualified engineer

Annual professional servicing should include refrigerant pressure checks, electrical testing, coil cleaning, and performance verification. Regular servicing maximizes efficiency, extends equipment life, and maintains warranty coverage. Many suppliers offer annual service contracts for peace of mind.

Troubleshooting Questions

Q: My dehumidifier is running but humidity isn’t coming down. What’s wrong?

A: Common causes include:

1. Dirty air filters (most common) – clean or replace immediately
2. Humidistat set too high – check setting and lower if needed
3. Excessive moisture sources – uncovered pool, excessive splashing, water features
4. Air leaks in building – cold air infiltration brings moisture in
5. Undersized unit – pool hall may be larger than unit capacity
6. Low refrigerant – requires professional diagnosis and recharge
7. Recent heavy usage – system may need 48+ hours to regain control

If filters are clean and settings are correct, contact a service engineer.

Q: Why does my dehumidifier keep cycling on and off?

A: Short cycling can be caused by:

• Humidistat reached setpoint – this is normal operation
• Dirty filters – causes overheating and safety cutout
• Restricted airflow – check for obstructions around intake/discharge
• Oversized for application – unit reaches setpoint quickly, cycles frequently
• Electrical issues – faulty components or control board

If cycling is excessive (more than 4-6 times per hour), investigate filter cleanliness, airflow obstructions, and humidistat calibration. Persistent problems require professional diagnosis.

Q: Can I use the Monitair 110 in a spa or hot tub room instead of a swimming pool?

A: Yes! The Monitair 110 is suitable for spa and hot tub facilities, though you may need to adjust your expectations:

• Hot tubs evaporate more due to higher water temperatures (often 38-40°C vs 28°C for pools)
• Smaller spaces mean concentrated moisture in confined areas
• Higher humidity challenges may require more frequent operation

For dedicated hot tub rooms, ensure adequate ventilation alongside dehumidification, and consider setting the humidistat to 55% RH (slightly lower than pool halls) to compensate for the higher evaporation rate.

Warranty & Support

Manufacturer Warranty

The Monitair 110 is covered by a comprehensive 2-year parts and labour warranty provided by Certikin International Ltd, covering:

✅ Manufacturing defects
✅ Component failures under normal use
✅ Labour costs for warranty repairs
✅ Replacement parts

Warranty Conditions:

• Unit must be installed by a qualified professional
• Annual professional servicing recommended (may be required for warranty validity)
• Excludes damage from improper installation, neglect, or unauthorized modifications
• Register your unit after installation for warranty activation

Downloads & Technical Documentation

📄 Monitair 110 Technical Datasheet (PDF) (opens in new tab)
Complete specifications, dimensions, electrical data, and installation drawings for the DH110AX. Essential for installers and specifiers.

📄 Vaporex & Monitair Product Brochure 2022 (PDF) (opens in new tab)
Overview of the complete Calorex dehumidifier range including the Monitair 75, 110, and alternative models. Includes comparative specifications and model selection guidance.

📄 Guidelines to Pool Hall Construction 2022 (PDF) (opens in new tab)
Comprehensive guide to designing and constructing indoor pool halls, covering insulation, vapor barriers, glazing, ventilation, and best practices for controlling moisture and condensation. Essential reading for architects, builders, and pool facility planners.

Why Choose the Monitair 110 from Parts4Tubs?

✅ Genuine Certikin Equipment – Factory-direct authentic products
✅ Expert Technical Support – Our team understands pool hall dehumidification
✅ Competitive Pricing – Best value for professional-grade equipment
✅ Fast UK Delivery – Quick dispatch to keep your project on schedule
✅ 2-Year Warranty – Full manufacturer backing with nationwide service support

Product Summary

The DH110AX Monitair 110 is a professional-grade swimming pool dehumidifier that combines powerful 108 L/day moisture removal with energy-efficient heat recovery and optional LPHW air heating. Ideal for domestic and commercial indoor pools up to approximately 50m² surface area, it protects your building structure from moisture damage while creating a comfortable, healthy swimming environment.

With advanced defrost capability for year-round operation, flexible installation options (wall mount or through-wall), and the backing of Certikin’s 2-year warranty, the Monitair 110 represents a reliable, cost-effective solution for indoor pool climate control.

Key Specifications Recap:

• 4.5 L/hr (108 L/day) dehumidification
• 6.4 kW heat recovery (12.2 kW with LPHW option)
• Single-phase 230V operation
• 48.5 dB(A) quiet operation
• R407C eco-friendly refrigerant
• 2-year parts & labour warranty

Transform your indoor pool hall into a dry, comfortable, and protected space with the Monitair 110 dehumidifier.