MVHR Units with Cooling: Can You Cool Your Home with Heat Recovery Ventilation?

As modern homes become more airtight and energy-efficient, keeping indoor temperatures comfortable throughout the year is becoming increasingly important. While insulation and airtightness help retain warmth during winter, they can also make it more difficult to manage overheating during the warmer months.

This has led many homeowners, architects and developers to explore MVHR units with cooling as a way to combine fresh air ventilation with improved summer comfort.

But can an MVHR system actually cool your home? And what's the difference between a standard MVHR unit with summer bypass and an MVHR system with active cooling?

In this guide, we'll explain how MVHR cooling works, what systems are available and how to choose the right solution for your property.

Can an MVHR Unit Cool Your Home?

Yes, an MVHR system can help cool your home, but the level of cooling depends on the type of system installed.

Standard Mechanical Ventilation with Heat Recovery (MVHR) systems are primarily designed to provide continuous fresh, filtered air while recovering heat from extracted air.

Many modern MVHR units feature a summer bypass function, allowing cooler outdoor air to enter the home without being warmed by the heat exchanger.

However, summer bypass does not actively refrigerate the air.

For homeowners looking for additional cooling, specialist MVHR cooling systems can incorporate compatible cooling modules or integrated heating and cooling technology to reduce the temperature of incoming supply air.

How Does MVHR Cooling Work?

There are two main approaches to cooling with an MVHR system.

1. MVHR Summer Bypass – Passive Cooling

Summer bypass is a common feature of modern heat recovery ventilation units.

During winter, an MVHR system transfers heat from outgoing stale air to incoming fresh air, helping reduce heat loss.

During warmer weather, when indoor temperatures are high and the outside air is cooler, summer bypass allows incoming air to avoid the heat exchanger.

For example:

• Indoor temperature: 25°C
• Outdoor temperature: 18°C
• Summer bypass allows the system to supply cooler outdoor air without recovering unwanted heat from the extracted air.

This can help moderate indoor temperatures, particularly during cooler evenings and overnight.

However, summer bypass cannot cool incoming air below the outdoor temperature. It is not a replacement for air conditioning.

2. MVHR with Active Cooling – Comfort Cooling

For greater temperature control, specialist MVHR cooling systems use additional cooling technology.

These systems may incorporate a cooling module or heat pump to actively lower the temperature of the air supplied to living areas and bedrooms.

Unlike standard summer bypass, active cooling can reduce supply-air temperatures below the outdoor temperature, depending on the system design and operating conditions.

This can be particularly useful in:

• Modern airtight new-build homes
• Energy-efficient properties experiencing summer overheating
• Apartments with limited opportunities for natural ventilation
• Homes where continuous fresh air and additional cooling are both priorities

The effectiveness of MVHR comfort cooling depends on the airflow available, cooling capacity, ductwork design and overall cooling requirements of the property.

MVHR Units with Cooling Available from BPC Ventilation

At BPC Ventilation, we offer specialist MVHR cooling solutions designed to combine ventilation with improved temperature control.

Zehnder ComfoClime Q600 Kit

The Zehnder ComfoClime Q600 Kit combines heat recovery ventilation with a compatible comfort cooling and heating module.

Designed to work with the Zehnder ComfoAir Q ventilation system, it helps regulate supply-air temperatures throughout the year.

Key features include:

• Up to 2.6kW cooling capacity, depending on configuration and operating conditions
• Supplementary heating capability
• High-efficiency heat recovery ventilation
• Smart controls and app functionality
• Summer bypass operation
• Options incorporating a standard or enthalpy heat exchanger

The ComfoClime system is an option for homeowners seeking improved summer comfort without relying entirely on a separate cooling system.

Nuaire MRXBOXAB Hybrid Cooling Kit

The Nuaire MRXBOXAB Hybrid Cooling Kit combines an MVHR unit with a dedicated cooling module.

Designed to help mitigate overheating, the system supplies filtered fresh air while providing additional cooling during warmer weather.

Key features include:

• Integrated MVHR and comfort cooling solution
• Dedicated cooling module for incoming supply air
• Automatic summer bypass
• Humidity-responsive ventilation
• Suitable for appropriately designed residential ventilation systems

The Nuaire Hybrid Cooling Kit is particularly relevant to projects where summer overheating is a concern and additional supply-air cooling is required.

You can explore the available products in our MVHR Cooling collection.

MVHR Cooling vs Air Conditioning: What's the Difference?

Although both systems can contribute to a comfortable indoor environment, they serve different purposes.

MVHR ventilation continuously extracts stale air and introduces fresh, filtered outdoor air. With compatible cooling equipment, it can also provide additional supply-air cooling.

Air conditioning is primarily designed to control indoor temperatures and can generally deliver greater room cooling capacity. Most conventional split air-conditioning systems recirculate indoor air and do not independently provide the fresh air ventilation required for a property.

MVHR comfort cooling can be an excellent addition to a ventilation system, but it should not automatically be considered a replacement for conventional air conditioning.

The best solution depends on the cooling load, property layout, available airflow and the level of temperature control required.

Can You Add Cooling to an Existing MVHR System?

In some cases, cooling can be added to an existing MVHR installation, but compatibility and system design are essential.

Before introducing a cooling module, several factors should be considered:

• MVHR compatibility: Not every ventilation unit supports a cooling module.
• Airflow requirements: Additional cooling may require higher airflow rates than those used for standard ventilation.
• Ductwork insulation: Correct insulation is important to reduce unwanted heat gain and condensation risk.
• Condensate management: Cooling equipment may require suitable drainage and moisture control.
• System controls: The ventilation and cooling components need compatible control arrangements.
• Property cooling requirements: The cooling capacity must be appropriate for the home's overheating risk and intended use.

Because MVHR systems are primarily designed around ventilation airflow, adding a cooler does not guarantee effective whole-home cooling.

For this reason, we recommend reviewing the complete ventilation design before selecting a cooling solution.

Is MVHR Cooling Worth It in the UK?

MVHR cooling can be a worthwhile option for UK homeowners who want to improve indoor comfort while maintaining continuous fresh air ventilation.

Its main advantages can include:

• Improved summer comfort

• Continuous filtered fresh air

• Integration with heat recovery ventilation

• Reduced reliance on window opening for ventilation

• More discreet temperature control through a central ducted system

• Combined ventilation and comfort cooling in one coordinated design

However, performance will vary between properties. Solar shading, glazing, insulation, orientation and other factors all influence how much cooling is needed.

The Passivhaus Trust's guidance on avoiding summer overheating also highlights the importance of combining ventilation with measures that reduce overheating in the first place.

Is MVHR cooling suitable for a new build?

Yes. A new-build project provides an opportunity to consider ventilation, cooling, ductwork routes, insulation and overheating prevention together from the early design stages.

Find the Right MVHR Cooling System with BPC Ventilation

Choosing an MVHR unit with cooling involves more than selecting a heat recovery unit with summer bypass.

The right system must provide suitable ventilation airflow, cooling performance and ductwork design for your property.

At BPC Ventilation, the UK's No. 1 Independent MVHR Supplier, we specialise in MVHR system design and supply, helping homeowners, installers, architects and developers find ventilation solutions suited to their projects.

Whether you're planning a new build, upgrading an existing ventilation system or exploring comfort cooling options, our team can help you assess the available solutions.

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Alternatively, explore our MVHR cooling systems and discover the available options for your property.