Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m²
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Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m²

Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m²

$10,346.87
Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m²
$10,346.87

The Story

The Vectaire Cool Breeze Plus is supplied as a complete system with the Vectaire Maxi Plus BY MVHR unit — combining whole-house mechanical ventilation with heat recovery and active overheating mitigation for larger residential properties up to 400 m². The Maxi Plus BY provides continuous fresh filtered air with up to 89% heat recovery efficiency and a peak airflow of 238 l/s, while the Cool Breeze Plus actively cools the incoming supply air by up to 20°C — delivering up to 4.3 kW of total cooling capacity without any external condenser unit. The system uses R290, a natural refrigerant with a Global Warming Potential of just 3 — over 225 times more environmentally friendly than R32 — achieving an outstanding COP of up to 6.5 and EER of up to 4.6. Together, the Cool Breeze Plus and Maxi Plus BY meet the overheating assessment standards of CIBSE TM59 and Approved Document O of the UK Building Regulations, providing developers, architects, and self-builders with a fully compliant, high-efficiency, no-external-condenser solution for year-round indoor climate control in larger homes.

4.3 kW
Max Cooling Capacity
89%
Maxi Plus BY Heat Recovery
20°C
Max Supply Air Drop
COP 6.5
Coefficient of Performance
GWP 3
R290 Natural Refrigerant
400 m²
Max Property Size
Installer Note: The Cool Breeze Plus uses R290 (propane) — a flammable refrigerant classified A3. Installation of the refrigerant circuit must be carried out by a suitably qualified F-Gas or equivalent refrigerant engineer in accordance with relevant safety regulations. The system is sealed for life and must not be modified or recharged. Ensure adequate ventilation in the installation location. The Maxi Plus BY must be installed and commissioned in accordance with Building Regulations Part F. Allow 200 mm clearance each side of the Maxi Plus BY cabinet for motor access. The combined system weighs up to 103 kg — ensure adequate structural support in the plant room or loft.
Supplied Together — Maxi Plus BY MVHR + Cool Breeze Plus: This listing covers the complete Cool Breeze Plus system as supplied with the Vectaire Maxi Plus BY MVHR. The Cool Breeze Plus cooling module is engineered exclusively for the Maxi Plus BY and is not compatible with any other MVHR unit. For smaller properties up to 250 m², the Cool Breeze with Maxi is the correct system. Wall bracket or floor stand required for the cooling module — available separately. Confirm handing and installation configuration before ordering. Humidistat variants of the Maxi Plus BY have factory-set handing — confirm left or right drain direction at point of order.
Approved Document O & CIBSE TM59 Compliant — Passive House Certified Option Available. The Cool Breeze Plus + Maxi Plus BY combination meets the overheating assessment standards of CIBSE TM59 and Approved Document O of the UK Building Regulations. The Maxi Plus BY is SAP PCDB Listed and CE marked, manufactured in the UK to ISO 9001:2015 and ISO 14001:2015. A Passive House Certified variant of the Maxi Plus BY is available for Passivhaus projects. The Cool Breeze Plus is a Vectaire Registered Design.
Cool Breeze Plus — Cooling Module Features
R290 — Outstanding GWP & Efficiency

The Cool Breeze Plus uses R290 (propane) with a GWP of just 3 — over 225 times more environmentally friendly than R32. This natural refrigerant delivers exceptional thermodynamic performance, enabling a COP of up to 6.5 and EER of up to 4.6 — significantly outperforming most domestic air conditioning systems in efficiency. This means lower electricity bills for occupants and a dramatically reduced refrigerant climate impact over the product's lifetime.

4.3 kW Cooling — No External Condenser

The sealed-for-life system delivers up to 4.3 kW of total cooling at 815 W of electrical consumption. The internal condenser rejects heat through the Maxi Plus BY's exhaust airstream — no external condenser unit is required. This eliminates planning constraints, external fan noise, and the visual impact of conventional AC equipment on new-build facades or existing properties.

Cools Supply Air by Up to 20°C

The Cool Breeze Plus removes heat from the Maxi Plus BY's fresh supply airstream before it is distributed throughout the home. At 30°C external / 23°C internal and 110 l/s airflow, the supply air temperature reaches 14.8°C with a total cooling power of 2.56 kW at 50% relative humidity. At 35°C external and 110 l/s, cooling output reaches 3.19 kW — providing substantial comfort cooling through the existing ductwork.

High Capacity — Up to 160 l/s Airflow

The Cool Breeze Plus is engineered for the higher airflows of the Maxi Plus BY, handling up to 160 l/s — significantly more than the standard Cool Breeze (140 l/s). This larger airflow envelope ensures the cooling module keeps pace with the Maxi Plus BY's capacity across the full range of larger homes it is designed to serve, maintaining consistent comfort even in the largest open-plan spaces.

Automatic Integral Sensor Control

The Cool Breeze Plus automatically senses both room temperature and the incoming fresh air temperature via an integral sensor, activating cooling only when conditions require it. This prevents false triggering and optimises energy consumption. An optional manual override allows occupants to control cooling to their own preference. Universal handing via intelligent software means no mechanical adjustment is required on site.

Very Quiet — Front Service Access

The very quiet integral condenser rejects heat through the Maxi Plus BY's exhaust duct rather than via an external fan. At 100% (180 l/s) breakout sound pressure is 43.3 dBA at 3 m; at 60% (100 l/s) this falls to 34.2 dBA. All servicing is via front access panels — no additional side or rear clearance is needed for the cooling module beyond the Maxi Plus BY's standard 200 mm motor clearance requirement.

Wall or Floor Installation

The Cool Breeze Plus + Maxi Plus BY can be installed in wall-mounted or floor-standing configurations using the appropriate wall bracket or floor stand (available separately). The combined unit is 818 mm wide and 1599 mm tall in the wall bracket arrangement (1405 mm on a floor stand) — suitable for plant rooms, utility spaces, or loft installations with adequate head height and structural support for the combined 103 kg weight.

Fresh Air — Not Recirculated Air

Unlike a conventional split-system air conditioner, the Cool Breeze Plus cools fresh outdoor air as it enters the home through the Maxi Plus BY MVHR — it never recirculates stale indoor air. Occupants receive continuous cooled, filtered fresh air distributed throughout the property, preserving the full indoor air quality benefits of MVHR alongside active cooling. Ideal for allergy sufferers, Passivhaus-adjacent designs, and high-specification new builds.

Vectaire Maxi Plus BY MVHR — Supplied with the Cool Breeze Plus
Up to 89% Counter-Flow Heat Recovery

The Maxi Plus BY's counter-flow heat exchanger achieves up to 89% thermal efficiency under SAP 10 conditions, recovering warmth from stale exhaust air without mixing the two airstreams. Even at the most demanding configuration (kitchen plus seven wet rooms), heat exchange efficiency remains at 84% — maintaining strong performance across the full range of large-home layouts.

238 l/s — Largest Capacity in the Vectaire Range

The Maxi Plus BY reaches a peak airflow of 238 l/s (857 m³/hr) at 100% speed — the highest capacity in the Vectaire residential MVHR range. This makes it the correct choice for large detached homes, open-plan new builds, and high-specification retrofit projects where a standard Maxi (177 l/s / 250 m²) would be insufficient. SFP is as low as 0.46 W/l/s, comfortably meeting Part L energy targets.

Automatic Summer Bypass & Frost-Stat

The Maxi Plus BY includes a fully automatic summer bypass and an integral frost-stat as standard. The bypass routes incoming air around the heat exchanger automatically during mild weather; the frost-stat proportionally reduces intake fan speed as outside temperatures fall between +3°C and −8°C — protecting the heat exchanger through UK winters without a separate controller.

EC Motors, Smart Controls & BMS Integration

High-quality EC brushless motors power five speed steps from 35 l/s to 238 l/s, drawing just 8 W at 20% and 355 W at 100%. Factory-set options include 0-10V connections for BMS, CO₂ detection, and home automation; integral humidistat; holiday mode; relay for external pre-heater; and run-time counters downloadable via QR code. Optional integral or remote LCD commissioning unit for precise airflow balancing.

Technical Specifications — Cool Breeze Plus Cooling Module
Max Total Cooling Capacity 4.3 kW
Power Consumption 815 W
Full Load Current (FLC) 5.5 A
COP (max) 6.5
EER (max) 4.6
Refrigerant R290 (propane) — natural refrigerant, GWP 3
Max Supply Air Temperature Reduction Up to 20°C
Max Airflow (cooling module) 160 l/s
Breakout Sound Pressure @ 3m 43.3 dBA @ 100% (180 l/s) · 34.2 dBA @ 60% (100 l/s)
Cooling Unit Weight 66 kg
Installation Options Wall mounted or floor standing (bracket/stand sold separately)
Handing Universal via intelligent software
Servicing Access Front access
Technical Specifications — Vectaire Maxi Plus BY MVHR (Supplied With)
Max Airflow Capacity 238 l/s (857 m³/hr)
Airflow at 50Pa 230 l/s
Heat Exchange Efficiency (max) 89% (SAP 10: Kitchen + 1 wet room)
Specific Fan Power (SFP) Down to 0.46 W/l/s
Total Power — 100% / 20% 355 W / 8 W
Operating Current 2.81 A
Airflow Speeds (l/s) 238 / 186 / 135 / 84 / 35 (100%–20%)
Breakout Sound Pressure @ 3m 43.1 dBA @ 100% · 20.4 dBA @ 20%
Frost-Stat Activation Range +3°C to −8°C (outside temperature)
Filter Grade G3 disposable, easily accessible
Maxi Plus BY Weight 37 kg (Maxi Plus BY) · 42 kg (Maxi Plus-AT)
Duct Connection Diameter Ø149 mm
Combined Height — Wall Bracket 1599 mm
Combined Height — Floor Stand 1405 mm
Combined Width 818 mm (front) · 823 mm (rear)
Combined System Weight 103 kg (Cool Breeze Plus 66 kg + Maxi Plus BY 37 kg)
Warranty (Maxi Plus BY) 5 years (1 year parts & labour, 4 years parts only)
Certifications SAP PCDB Listed · CE Marked · ISO 9001:2015 · ISO 14001:2015 · EU RoHS
System Compliance CIBSE TM59 · Approved Document O · Building Regulations Part F & Part L
Sound Testing Standard BS EN ISO 3743-1:2010 (independently tested)
Manufacturer Vectaire Ltd, High Wycombe, UK
Frequently Asked Questions
What does this listing include — is the Maxi Plus BY MVHR supplied with the Cool Breeze Plus?
Yes. The Cool Breeze Plus is supplied as a complete system with the Vectaire Maxi Plus BY MVHR. The two units are engineered exclusively to work together: the Maxi Plus BY handles year-round fresh air ventilation and heat recovery for homes up to 400 m², and the Cool Breeze Plus actively cools the incoming supply air during warmer months. The Cool Breeze Plus is not compatible with any other MVHR unit.
What is the difference between this system and the Cool Breeze with Maxi?
The Cool Breeze + Maxi is the system for homes up to 250 m², with a peak MVHR airflow of 177 l/s and up to 4.1 kW cooling at COP 4.3 / EER 3.2. The Cool Breeze Plus + Maxi Plus BY is the system for larger homes up to 400 m², with a peak airflow of 238 l/s and up to 4.3 kW cooling at a significantly higher COP of 6.5 and EER of 4.6. The two systems are not interchangeable.
Does this system satisfy Approved Document O?
Yes. The Cool Breeze Plus + Maxi Plus BY meets the standards used in CIBSE TM59 overheating assessments and Approved Document O of the UK Building Regulations. It provides architects, developers, and self-builders with a fully documented, compliant overheating mitigation route for larger new residential buildings subject to Part O requirements. Contact Casavent for full overheating assessment documentation support.
Can this system be used in a Passivhaus project?
A Passive House Certified variant of the Maxi Plus BY is available, making the complete system eligible for use in Passivhaus certified dwellings where the Passivhaus Institut's strict heat recovery and airtightness requirements must be demonstrated. Contact Casavent for Passivhaus-specific system design, documentation, and certification support for your project.
How does a COP of 6.5 compare to conventional air conditioning?
A COP of 6.5 means the Cool Breeze Plus delivers 6.5 units of cooling energy for every 1 unit of electricity consumed — significantly more efficient than most domestic split-system air conditioners, which typically achieve COPs of 3–4. This is partly attributable to R290's excellent thermodynamic properties and partly to the system's unique operating condition of using the MVHR exhaust airstream for heat rejection rather than ambient outdoor air.
What support does Casavent provide for Cool Breeze Plus projects?
Casavent provides full end-to-end design support for Cool Breeze Plus + Maxi Plus BY projects, including overheating assessment guidance, full system specification and design, CAD drawings, airflow and pressure calculations, and complete component breakdowns. As members of the Young's Extract Supplies Group and specialists in residential ventilation, Casavent supports self-builders, contractors, architects, and developers from initial specification through to commissioning.
Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m² - Image 2

Details & Craftsmanship

Every detail has been carefully considered to bring you the perfect product.

Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m² - Image 3

Details & Craftsmanship

Every detail has been carefully considered to bring you the perfect product.

Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m² - Image 4

Details & Craftsmanship

Every detail has been carefully considered to bring you the perfect product.

Vectaire Cool Breeze Plus with Maxi Plus BY MVHR — Active Cooling and Heat Recovery System for Homes up to 400m² - Image 5

Details & Craftsmanship

Every detail has been carefully considered to bring you the perfect product.

Description

The Vectaire Cool Breeze Plus is supplied as a complete system with the Vectaire Maxi Plus BY MVHR unit — combining whole-house mechanical ventilation with heat recovery and active overheating mitigation for larger residential properties up to 400 m². The Maxi Plus BY provides continuous fresh filtered air with up to 89% heat recovery efficiency and a peak airflow of 238 l/s, while the Cool Breeze Plus actively cools the incoming supply air by up to 20°C — delivering up to 4.3 kW of total cooling capacity without any external condenser unit. The system uses R290, a natural refrigerant with a Global Warming Potential of just 3 — over 225 times more environmentally friendly than R32 — achieving an outstanding COP of up to 6.5 and EER of up to 4.6. Together, the Cool Breeze Plus and Maxi Plus BY meet the overheating assessment standards of CIBSE TM59 and Approved Document O of the UK Building Regulations, providing developers, architects, and self-builders with a fully compliant, high-efficiency, no-external-condenser solution for year-round indoor climate control in larger homes.

4.3 kW
Max Cooling Capacity
89%
Maxi Plus BY Heat Recovery
20°C
Max Supply Air Drop
COP 6.5
Coefficient of Performance
GWP 3
R290 Natural Refrigerant
400 m²
Max Property Size
Installer Note: The Cool Breeze Plus uses R290 (propane) — a flammable refrigerant classified A3. Installation of the refrigerant circuit must be carried out by a suitably qualified F-Gas or equivalent refrigerant engineer in accordance with relevant safety regulations. The system is sealed for life and must not be modified or recharged. Ensure adequate ventilation in the installation location. The Maxi Plus BY must be installed and commissioned in accordance with Building Regulations Part F. Allow 200 mm clearance each side of the Maxi Plus BY cabinet for motor access. The combined system weighs up to 103 kg — ensure adequate structural support in the plant room or loft.
Supplied Together — Maxi Plus BY MVHR + Cool Breeze Plus: This listing covers the complete Cool Breeze Plus system as supplied with the Vectaire Maxi Plus BY MVHR. The Cool Breeze Plus cooling module is engineered exclusively for the Maxi Plus BY and is not compatible with any other MVHR unit. For smaller properties up to 250 m², the Cool Breeze with Maxi is the correct system. Wall bracket or floor stand required for the cooling module — available separately. Confirm handing and installation configuration before ordering. Humidistat variants of the Maxi Plus BY have factory-set handing — confirm left or right drain direction at point of order.
Approved Document O & CIBSE TM59 Compliant — Passive House Certified Option Available. The Cool Breeze Plus + Maxi Plus BY combination meets the overheating assessment standards of CIBSE TM59 and Approved Document O of the UK Building Regulations. The Maxi Plus BY is SAP PCDB Listed and CE marked, manufactured in the UK to ISO 9001:2015 and ISO 14001:2015. A Passive House Certified variant of the Maxi Plus BY is available for Passivhaus projects. The Cool Breeze Plus is a Vectaire Registered Design.
Cool Breeze Plus — Cooling Module Features
R290 — Outstanding GWP & Efficiency

The Cool Breeze Plus uses R290 (propane) with a GWP of just 3 — over 225 times more environmentally friendly than R32. This natural refrigerant delivers exceptional thermodynamic performance, enabling a COP of up to 6.5 and EER of up to 4.6 — significantly outperforming most domestic air conditioning systems in efficiency. This means lower electricity bills for occupants and a dramatically reduced refrigerant climate impact over the product's lifetime.

4.3 kW Cooling — No External Condenser

The sealed-for-life system delivers up to 4.3 kW of total cooling at 815 W of electrical consumption. The internal condenser rejects heat through the Maxi Plus BY's exhaust airstream — no external condenser unit is required. This eliminates planning constraints, external fan noise, and the visual impact of conventional AC equipment on new-build facades or existing properties.

Cools Supply Air by Up to 20°C

The Cool Breeze Plus removes heat from the Maxi Plus BY's fresh supply airstream before it is distributed throughout the home. At 30°C external / 23°C internal and 110 l/s airflow, the supply air temperature reaches 14.8°C with a total cooling power of 2.56 kW at 50% relative humidity. At 35°C external and 110 l/s, cooling output reaches 3.19 kW — providing substantial comfort cooling through the existing ductwork.

High Capacity — Up to 160 l/s Airflow

The Cool Breeze Plus is engineered for the higher airflows of the Maxi Plus BY, handling up to 160 l/s — significantly more than the standard Cool Breeze (140 l/s). This larger airflow envelope ensures the cooling module keeps pace with the Maxi Plus BY's capacity across the full range of larger homes it is designed to serve, maintaining consistent comfort even in the largest open-plan spaces.

Automatic Integral Sensor Control

The Cool Breeze Plus automatically senses both room temperature and the incoming fresh air temperature via an integral sensor, activating cooling only when conditions require it. This prevents false triggering and optimises energy consumption. An optional manual override allows occupants to control cooling to their own preference. Universal handing via intelligent software means no mechanical adjustment is required on site.

Very Quiet — Front Service Access

The very quiet integral condenser rejects heat through the Maxi Plus BY's exhaust duct rather than via an external fan. At 100% (180 l/s) breakout sound pressure is 43.3 dBA at 3 m; at 60% (100 l/s) this falls to 34.2 dBA. All servicing is via front access panels — no additional side or rear clearance is needed for the cooling module beyond the Maxi Plus BY's standard 200 mm motor clearance requirement.

Wall or Floor Installation

The Cool Breeze Plus + Maxi Plus BY can be installed in wall-mounted or floor-standing configurations using the appropriate wall bracket or floor stand (available separately). The combined unit is 818 mm wide and 1599 mm tall in the wall bracket arrangement (1405 mm on a floor stand) — suitable for plant rooms, utility spaces, or loft installations with adequate head height and structural support for the combined 103 kg weight.

Fresh Air — Not Recirculated Air

Unlike a conventional split-system air conditioner, the Cool Breeze Plus cools fresh outdoor air as it enters the home through the Maxi Plus BY MVHR — it never recirculates stale indoor air. Occupants receive continuous cooled, filtered fresh air distributed throughout the property, preserving the full indoor air quality benefits of MVHR alongside active cooling. Ideal for allergy sufferers, Passivhaus-adjacent designs, and high-specification new builds.

Vectaire Maxi Plus BY MVHR — Supplied with the Cool Breeze Plus
Up to 89% Counter-Flow Heat Recovery

The Maxi Plus BY's counter-flow heat exchanger achieves up to 89% thermal efficiency under SAP 10 conditions, recovering warmth from stale exhaust air without mixing the two airstreams. Even at the most demanding configuration (kitchen plus seven wet rooms), heat exchange efficiency remains at 84% — maintaining strong performance across the full range of large-home layouts.

238 l/s — Largest Capacity in the Vectaire Range

The Maxi Plus BY reaches a peak airflow of 238 l/s (857 m³/hr) at 100% speed — the highest capacity in the Vectaire residential MVHR range. This makes it the correct choice for large detached homes, open-plan new builds, and high-specification retrofit projects where a standard Maxi (177 l/s / 250 m²) would be insufficient. SFP is as low as 0.46 W/l/s, comfortably meeting Part L energy targets.

Automatic Summer Bypass & Frost-Stat

The Maxi Plus BY includes a fully automatic summer bypass and an integral frost-stat as standard. The bypass routes incoming air around the heat exchanger automatically during mild weather; the frost-stat proportionally reduces intake fan speed as outside temperatures fall between +3°C and −8°C — protecting the heat exchanger through UK winters without a separate controller.

EC Motors, Smart Controls & BMS Integration

High-quality EC brushless motors power five speed steps from 35 l/s to 238 l/s, drawing just 8 W at 20% and 355 W at 100%. Factory-set options include 0-10V connections for BMS, CO₂ detection, and home automation; integral humidistat; holiday mode; relay for external pre-heater; and run-time counters downloadable via QR code. Optional integral or remote LCD commissioning unit for precise airflow balancing.

Technical Specifications — Cool Breeze Plus Cooling Module
Max Total Cooling Capacity 4.3 kW
Power Consumption 815 W
Full Load Current (FLC) 5.5 A
COP (max) 6.5
EER (max) 4.6
Refrigerant R290 (propane) — natural refrigerant, GWP 3
Max Supply Air Temperature Reduction Up to 20°C
Max Airflow (cooling module) 160 l/s
Breakout Sound Pressure @ 3m 43.3 dBA @ 100% (180 l/s) · 34.2 dBA @ 60% (100 l/s)
Cooling Unit Weight 66 kg
Installation Options Wall mounted or floor standing (bracket/stand sold separately)
Handing Universal via intelligent software
Servicing Access Front access
Technical Specifications — Vectaire Maxi Plus BY MVHR (Supplied With)
Max Airflow Capacity 238 l/s (857 m³/hr)
Airflow at 50Pa 230 l/s
Heat Exchange Efficiency (max) 89% (SAP 10: Kitchen + 1 wet room)
Specific Fan Power (SFP) Down to 0.46 W/l/s
Total Power — 100% / 20% 355 W / 8 W
Operating Current 2.81 A
Airflow Speeds (l/s) 238 / 186 / 135 / 84 / 35 (100%–20%)
Breakout Sound Pressure @ 3m 43.1 dBA @ 100% · 20.4 dBA @ 20%
Frost-Stat Activation Range +3°C to −8°C (outside temperature)
Filter Grade G3 disposable, easily accessible
Maxi Plus BY Weight 37 kg (Maxi Plus BY) · 42 kg (Maxi Plus-AT)
Duct Connection Diameter Ø149 mm
Combined Height — Wall Bracket 1599 mm
Combined Height — Floor Stand 1405 mm
Combined Width 818 mm (front) · 823 mm (rear)
Combined System Weight 103 kg (Cool Breeze Plus 66 kg + Maxi Plus BY 37 kg)
Warranty (Maxi Plus BY) 5 years (1 year parts & labour, 4 years parts only)
Certifications SAP PCDB Listed · CE Marked · ISO 9001:2015 · ISO 14001:2015 · EU RoHS
System Compliance CIBSE TM59 · Approved Document O · Building Regulations Part F & Part L
Sound Testing Standard BS EN ISO 3743-1:2010 (independently tested)
Manufacturer Vectaire Ltd, High Wycombe, UK
Frequently Asked Questions
What does this listing include — is the Maxi Plus BY MVHR supplied with the Cool Breeze Plus?
Yes. The Cool Breeze Plus is supplied as a complete system with the Vectaire Maxi Plus BY MVHR. The two units are engineered exclusively to work together: the Maxi Plus BY handles year-round fresh air ventilation and heat recovery for homes up to 400 m², and the Cool Breeze Plus actively cools the incoming supply air during warmer months. The Cool Breeze Plus is not compatible with any other MVHR unit.
What is the difference between this system and the Cool Breeze with Maxi?
The Cool Breeze + Maxi is the system for homes up to 250 m², with a peak MVHR airflow of 177 l/s and up to 4.1 kW cooling at COP 4.3 / EER 3.2. The Cool Breeze Plus + Maxi Plus BY is the system for larger homes up to 400 m², with a peak airflow of 238 l/s and up to 4.3 kW cooling at a significantly higher COP of 6.5 and EER of 4.6. The two systems are not interchangeable.
Does this system satisfy Approved Document O?
Yes. The Cool Breeze Plus + Maxi Plus BY meets the standards used in CIBSE TM59 overheating assessments and Approved Document O of the UK Building Regulations. It provides architects, developers, and self-builders with a fully documented, compliant overheating mitigation route for larger new residential buildings subject to Part O requirements. Contact Casavent for full overheating assessment documentation support.
Can this system be used in a Passivhaus project?
A Passive House Certified variant of the Maxi Plus BY is available, making the complete system eligible for use in Passivhaus certified dwellings where the Passivhaus Institut's strict heat recovery and airtightness requirements must be demonstrated. Contact Casavent for Passivhaus-specific system design, documentation, and certification support for your project.
How does a COP of 6.5 compare to conventional air conditioning?
A COP of 6.5 means the Cool Breeze Plus delivers 6.5 units of cooling energy for every 1 unit of electricity consumed — significantly more efficient than most domestic split-system air conditioners, which typically achieve COPs of 3–4. This is partly attributable to R290's excellent thermodynamic properties and partly to the system's unique operating condition of using the MVHR exhaust airstream for heat rejection rather than ambient outdoor air.
What support does Casavent provide for Cool Breeze Plus projects?
Casavent provides full end-to-end design support for Cool Breeze Plus + Maxi Plus BY projects, including overheating assessment guidance, full system specification and design, CAD drawings, airflow and pressure calculations, and complete component breakdowns. As members of the Young's Extract Supplies Group and specialists in residential ventilation, Casavent supports self-builders, contractors, architects, and developers from initial specification through to commissioning.