National Ventilation Monsoon MON-DMEVR100 100mm Continuous Running Extractor Fan – IPX5 White

The National Ventilation Monsoon MON-DMEVR100 is a quiet, energy-efficient 100mm continuous running extractor fan designed to provide reliable background ventilation in bathrooms, kitchens, utility rooms and other domestic spaces.

Part of the Monsoon dMEV R range, this decentralised mechanical extract ventilation fan incorporates a high-pressure, low-noise impeller to deliver effective air extraction while maintaining quiet operation.

The manufacturer describes the range as operating at noise levels as low as 11dB(A), making it an attractive choice for residential properties where continuous ventilation is required without excessive noise.

Unlike conventional intermittent extractor fans, the MON-DMEVR100 operates continuously at a background extraction rate, helping remove moisture, stale air and airborne pollutants throughout the day.

When additional extraction is required, the fan can increase its ventilation rate using an appropriately connected external switching control.

The standard MON-DMEVR100 also incorporates a fixed overrun timer with Comfort Mode, helping manage boosted ventilation before returning to its background operating level.

Designed to support compliance with the applicable requirements of UK Building Regulations Part F and Part L, the Monsoon dMEV R is suitable for domestic ventilation installations where continuous mechanical extraction is specified.

With an IPX5 water-resistance rating, the fan is suitable for installation in bathroom Zones 1, 2 and 3, subject to correct installation and the manufacturer's instructions.

Its 100mm (4-inch) duct connection, discreet round white fascia and wall or ceiling mounting capability make it suitable for new-build properties, bathroom refurbishments and ventilation upgrades.

The Monsoon MON-DMEVR100 is the standard version of the dMEV R 100mm range and does not include an integrated humidity sensor.

Key Features

• 100mm (4-inch) continuous running extractor fan

• Monsoon dMEV R technology – decentralised mechanical extract ventilation

• Continuous background extraction – helps manage condensation and stale air

• Quiet operation – manufacturer-stated range noise levels as low as 11dB(A)

• High-pressure, low-noise impeller – designed for effective ventilation

• External boost control – increases extraction when required

• Fixed overrun timer – supports continued boosted ventilation

• Comfort Mode – integrated ventilation control feature

• Adjustable airflow settings – supports installation commissioning

• IPX5 water-resistance rating

• Suitable for bathroom Zones 1, 2 and 3, subject to correct installation

• Designed to support Building Regulations Part F and Part L

• 100mm duct connection – suitable for compatible 4-inch ducting

• Wall or ceiling mounting

• Round white fascia – discreet appearance

• Suitable for kitchens, utility rooms and bathrooms

• Standard model without integrated humidistat

Continuous Mechanical Extract Ventilation

The Monsoon MON-DMEVR100 is designed to operate continuously, providing a consistent level of background extraction.

This helps maintain airflow through moisture-prone rooms rather than relying solely on occasional periods of ventilation.

Continuous mechanical extract ventilation is particularly useful in modern, well-insulated properties where natural air movement may be limited.

The fan's adjustable operating settings allow the installer to configure the airflow to suit the requirements of the installation.

Quiet Running Performance

The Monsoon dMEV R range is designed for low-noise operation, with manufacturer-stated sound levels as low as 11dB(A).

Its high-pressure impeller is designed to provide effective ventilation while reducing unnecessary operating noise.

This makes the fan suitable for bathrooms, en-suites, utility rooms and other domestic spaces where quiet continuous operation is desirable.

Actual sound levels depend on the selected airflow setting, ductwork and installation conditions.

External Boost Control and Fixed Timer

The MON-DMEVR100 is the standard, non-humidistat version of the Monsoon dMEV R 100mm fan.

The fan provides continuous background ventilation and can be boosted through an appropriately wired external control.

It also features a fixed overrun timer with Comfort Mode, supporting continued extraction following boost activation.

For installations requiring automatic humidity-responsive ventilation, the MON-DMEVR100HT is the corresponding humidistat-equipped model.

IPX5 Bathroom Protection

The MON-DMEVR100 carries an IPX5 rating, providing protection against water jets.

The manufacturer specifies the Monsoon dMEV R range as suitable for bathroom Zones 1, 2 and 3 when correctly installed.

This makes it suitable for domestic bathroom ventilation projects where an appropriately water-resistant extractor fan is required.

Designed for UK Building Regulations

The Monsoon dMEV R range is designed to support the ventilation and energy-efficiency requirements of Building Regulations Part F and Part L.

Its continuous extraction operation makes it suitable for domestic ventilation designs specifying decentralised mechanical extract ventilation.

Compliance of the finished installation depends on correct product selection, ductwork design, airflow commissioning and installation.

Suitable Applications

• Domestic bathrooms

• Shower rooms

• En-suite bathrooms

• Kitchens

• Utility rooms

• Toilets and cloakrooms

• New-build residential properties

• Bathroom refurbishments

• Domestic ventilation upgrades

• Continuous mechanical extract ventilation installations

Bathroom zone suitability is subject to the manufacturer's instructions and applicable electrical regulations.

Frequently Asked Questions

What is the National Ventilation MON-DMEVR100?

The MON-DMEVR100 is a 100mm continuous running extractor fan designed to provide background ventilation in domestic bathrooms, kitchens and utility rooms.

Does the MON-DMEVR100 run continuously?

Yes. The fan is designed to operate continuously at a background extraction rate, with a higher ventilation setting available when required.

Does the MON-DMEVR100 have a humidity sensor?

No. The MON-DMEVR100 does not include an integrated humidistat.

For automatic humidity-responsive ventilation, choose the MON-DMEVR100HT.

Does the MON-DMEVR100 have a timer?

Yes. The installation instructions identify a fixed overrun timer with Comfort Mode on the standard MON-DMEVR100 model.

How is the boost function activated?

Boost operation can be activated using a suitable external switching arrangement, subject to the manufacturer's wiring instructions.

How quiet is the Monsoon dMEV R?

The manufacturer advertises noise levels as low as 11dB(A) across the range. Actual noise depends on the operating speed and installation conditions.

Is the MON-DMEVR100 suitable for bathroom Zone 1?

Yes. The fan is IPX5 rated, and the manufacturer specifies suitability for bathroom Zones 1, 2 and 3, subject to correct installation.

Can it be installed in a kitchen?

Yes. The Monsoon dMEV R range is designed for kitchens, bathrooms and utility rooms. The installation must be commissioned to meet the required ventilation rate.

Can the fan be ceiling mounted?

Yes. The MON-DMEVR100 is suitable for wall or ceiling mounting in accordance with the manufacturer's instructions.

What size ducting does it require?

The fan has a nominal 100mm (4-inch) duct connection.

What is the difference between MON-DMEVR100 and MON-DMEVR100HT?

The MON-DMEVR100 is the standard continuous running model with external boost control and a fixed timer.

The MON-DMEVR100HT includes an additional integrated humidity sensor for automatic humidity-responsive ventilation.

Both belong to the Monsoon dMEV R range and are IPX5 rated.

Is this an intermittent extractor fan?

No. It is a continuous running decentralised mechanical extract ventilation fan, designed to provide ongoing background extraction.

Installation Information

The National Ventilation Monsoon MON-DMEVR100 should be installed by a suitably competent person in accordance with the manufacturer's instructions and applicable requirements of BS 7671.

Suitable ductwork, electrical isolation and correct airflow commissioning are essential for reliable operation.

Where installed in a bathroom, the fan's IPX5 rating and the requirements of the relevant electrical zone must be considered as part of the complete installation.