Passyfier Core 140 Vent

Health & Safety Considerations

Work from a safe platform with good lighting and keep the area below cordoned off because masonry cores and debris can fall during drilling. Wear suitable work clothing together with safety goggles, cut-resistant gloves, hearing protection and a dust mask or respirator appropriate to core drilling.

Scan the wall for hidden services and structural features so you avoid cables, pipes, lintels and damp proof courses. Control dust with a vacuum attachment where possible and never leave debris in the cavity. Handle sealants and cleaners in line with the manufacturers’ guidance. If you are not confident using a Ø162mm Core Drill, engage a competent professional.

Site Preparation

Identify the problem room that suffers visible condensation or black mould and choose an external wall. The vent should be installed high on the wall with the top of the internal grille about 300mm below the ceiling. This position captures the warmest and most moisture-laden air and keeps any felt air movement away from occupant level.

Mark a location that is as far as practical from the doorway of the room and that is not hidden behind curtains or large furniture. In kitchens keep at least 1.5m from a cooker hood and, in both kitchens and bathrooms, retain mechanical extract because the vent handles background humidity rather than short-term peaks.

Measure the wall thickness. The telescopic tube set suits typical walls and adjusts from about 250mm to about 410mm. If the wall is thinner than 250mm the outer tube will need to be cut down on site.

Assemble the tools and materials you will need which include a Ø162mm Diamond Core Bit, a drill with a slow speed and clutch, a level, sealant and applicator, a small saw for trimming the tube, stainless steel screws for fixing and the supplied plastic wedge that creates the outward fall.

Limitations And Good Practice

The vent controls background moisture in habitable rooms and must not be used to supply combustion air to gas, oil or solid-fuel appliances. It does not replace compliant extractor fans in kitchens and bathrooms.

Always set the duct to fall towards the outside by at least 6mm so any incidental moisture drains away. Keep the internal grille clear and do not cover it with furniture or curtains. Choose an external position that is sheltered where practical.

Check that the red inner base label on the tube is positioned at the bottom when the duct is inserted so the fall is correct and condensate runs outward.

Step-By-Step Installation

1. Mark the position on the inside face at high level in the affected room. Use a level to set out the centre point and check there is clear access on the outside. Drill a small pilot hole through to the exterior to confirm the location.
   
   

2. Core drill a Ø162mm hole through the wall from inside to outside. Keep the drill level horizontally and allow a slight downward angle to the exterior so you create a natural fall. Use a vacuum attachment or an assistant to control dust and remove the core plug and debris from the hole.
   
   

3. Dry-fit the telescopic tube set. If the wall is less than 250mm thick, trim the outer tube carefully so the assembly seats flush. Ensure the red inner base label sits at the bottom when the tube is in the wall. Insert the supplied plastic wedge at the internal face if required to achieve a minimum 6mm fall to the outside.
   
   

4. Apply a neat bead of silicone to the rear flange of the external cowl. From outside, position the cowl over the hole, ensure it is level, then fix it to the wall using the stainless steel countersunk screws supplied. Tighten evenly so the sealant compresses and forms a weatherproof seal.
   
   

5. Slide the inner tube into the outer tube so the telescopic section matches the wall thickness without forcing. Check again that the assembly falls outward by at least 6mm. If the wall construction is uneven, use additional sealant around the annulus to prevent air bypassing the duct.
   
   

6. Fit the internal grille housing to the wall using the 19mm screws provided. Ensure it sits square and tight to the finish. Clip the white internal grille with integral flyscreen into the housing. If you need to remove it in future, insert a flat blade at the small release point and gently deflect the top edge towards the centre to unclip.
   
   

7. Make good around the penetrations if required, clean down the work area and dispose of debris responsibly. Carry out a simple functional check by holding a thin strip of tissue near the grille to confirm a gentle inward moderation of airflow and to verify that there are no obvious draughts.

Handover And Everyday Use

Explain to the household that the Passyfier Core 140 is a passive dehumidifier vent with no electrics and no running cost. It works continuously by allowing moisture vapour to diffuse outdoors while the external cowl reduces draughts.

Advise them to keep the grille unobstructed and to continue using extractor fans in kitchens and bathrooms during cooking and bathing. Remind them that the unit is most effective at high level and that any felt air movement will be minimal when furniture and curtains are kept clear.

Maintenance

The vent has no moving parts and needs only simple housekeeping. Once or twice a year, vacuum or wipe the internal grille and flyscreen to remove dust and cobwebs. After storms or heavy leaf fall, check that the external cowl is clear.

Inspect the perimeter sealant of the cowl every few years and renew if it shows signs of cracking. If the grille ever needs to be removed for cleaning, release it by inserting a flat blade at the indicated notch and gently deflecting the top edge.

Aftercare

Treat any existing mould on walls and ceilings with a quality fungicidal wash and allow surfaces to dry before repainting. Maintain steady background heat in colder months, keep internal doors undercut or slightly open to let moisture move towards the vent and continue to use mechanical extraction in wet rooms.

In larger open-plan spaces consider a second vent on an opposing wall to improve distribution. If the vent must be installed at low level, expect performance to reduce, which is why a high-level position about 300mm below the ceiling is preferred.

Other Information

The Passyfier Core 140 Dehumidifier Vent is designed for solid, cavity and timber-frame walls. Maximum indicative coverage is 10m² per vent and the unit can transmit up to 1.4L of water vapour per 24h under typical domestic conditions.

The main outer tube diameter is about 154mm and installation is by Ø162mm Core Drilling. The telescopic tube set adjusts to suit common wall thicknesses between about 250mm and 410mm.

The internal grille is white with an integral flyscreen measured at about 200mm by 200mm by 30mm. The external cowl is supplied in a choice of colours so the finish can be matched to the façade.

The unit is non-mechanical, silent in operation and costs nothing to run. It reduces draughts and heat loss while still providing passive background ventilation.

Q) What is the Passyfier Core 140 Dehumidifier Vent and what problem does it solve?

A) The Passyfier Core 140 Dehumidifier Vent is a through-the-wall, non-mechanical moisture control device for homes where condensation, window streaming and black mould appear in cooler months. It creates a controlled diffusion path so water vapour can escape naturally to outside without using a fan or electrics. Because it relies on vapour diffusion rather than bulk airflow, it tempers any felt air movement and limits heat loss, operating silently 24 hours a day with zero running cost. A single unit serves rooms up to 10m² and can transmit up to 1.4 litres of moisture per day under typical domestic conditions. Used alongside mechanical extract in kitchens and bathrooms, it keeps background humidity in bedrooms and living areas within a healthier band, protecting finishes and furnishings and helping the building fabric remain dry and stable.

Q) How does the Passyfier Core 140 Dehumidifier Vent work without a fan or power supply?

A) The Passyfier Core 140 exploits the natural difference in vapour pressure between warm indoor air and cooler outdoor air, especially during the heating season. Moisture molecules migrate through the vent’s warm, telescopic sleeve to the exterior, while the aerodynamically shaped cowl and the internal grille resist bulk airflow. This means the unit enables steady moisture diffusion rather than pulling cold air through the wall. The process is continuous, silent and has a negligible energy penalty. By allowing moisture to leave the home between high-intensity events such as cooking and showering, the vent lowers the likelihood that internal surfaces will reach dew point. The result is less window streaming, fewer damp corners and a noticeable reduction in the conditions that allow black mould to take hold, all without switches, sensors or running costs.

Q) Where should the Passyfier Core 140 Dehumidifier Vent be installed for best results?

A) Install the Passyfier Core 140 at high level on an external wall of the affected room, with the top of the internal grille about 300 mm below the ceiling. Warm, moisture-laden air pools near the ceiling, so a high-level position maximises vapour diffusion while keeping any slight air movement away from occupant level. Choose the colder corner that is furthest from the doorway and do not hide the grille behind curtains, wardrobes or pelmets because obstructions impede diffusion. In kitchens and bathrooms keep at least 1.5 m from cooker hoods and always retain mechanical extract because the vent is for background moisture rather than short-term peaks. For open-plan rooms consider two vents on opposing walls to improve distribution. Always set a slight outward fall so any incidental moisture drains to the exterior.

Q) What room size and moisture capacity does one Passyfier Core 140 Dehumidifier Vent cover?

A) One Passyfier Core 140 serves a room up to 10 m² and, in typical domestic conditions, can transmit up to 1.4 litres of water vapour per 24 hours. This is well suited to bedrooms, nurseries, home offices and compact living areas where background humidity accumulates after insulation upgrades. In larger rooms, heavily furnished spaces, or open-plan layouts, install a second unit on the opposing wall for even control. Treat the worst room first, then reassess before adding more vents. Remember that the vent addresses continuous background load; you should still use bathroom and kitchen extract fans during peak moisture events to clear short-term spikes quickly. With correct siting and routine housekeeping, most homes see a steady reduction in window condensation and cold-corner damp.

Q) Will the Passyfier Core 140 Dehumidifier Vent create draughts or increase heat loss?

A) The Passyfier Core 140 is designed to minimise felt draughts and thermal penalty. The shaped external cowl moderates pressure effects across the opening, and the internal grille tempers air movement, so you do not experience a free jet of outside air as with an open vent. Installed near the ceiling, any moderated air motion is kept above occupant level and is rarely noticed in normal use. The through-wall sleeve provides a warm pathway that favours vapour diffusion rather than bulk airflow, which limits heat loss compared with uncontrolled openings. Good detailing matters: set a small outward fall, seal neatly around the cowl and tube, and keep the grille clear of soft furnishings. In practice, rooms feel drier and more comfortable at the same thermostat setting because surfaces are less prone to condensation.

Q) Does the Passyfier Core 140 Dehumidifier Vent replace kitchen and bathroom extractor fans?

A) No. The Passyfier Core 140 provides passive background dehumidification and must be used alongside compliant mechanical extract in kitchens and bathrooms. Extract fans remove short-term humidity spikes from cooking and showering, while the Core 140 handles the ongoing moisture load in bedrooms and living areas between those events. This two-part strategy mirrors good building services practice and delivers the best results. Keep doors closed during moisture-producing activities and open them for cross-ventilation after steam has cleared. Allow the Core 140 to work continuously in the background, especially overnight when condensation risk is highest, so the home maintains a healthier humidity band without noise or user intervention.

Q) What is supplied with the Passyfier Core 140 Dehumidifier Vent and what tools are required to fit it?

A) The Passyfier Core 140 kit includes a robust telescopic tube set for a Ø162mm core-drilled opening, a white internal grille with built-in flyscreen, an external cowl in a choice of colours, colour-matched exterior fixings, and a plastic wedge to help you set a slight outward fall. A competent installer will need a Ø162mm Diamond Core Bit with a suitable drill and clutch, a level or straightedge, a small saw for trimming the tube on thinner walls, a quality exterior-grade silicone for the cowl flange, stainless screws and plugs, and basic hand tools for fixing and making good. The telescopic range covers typical walls from about 250 mm to about 410 mm; if the wall is thinner, the outer tube can be trimmed on site so the assembly sits flush and square.

Q) What are the key technical specifications of the Passyfier Core 140 Dehumidifier Vent?

A) The Passyfier Core 140 operates by passive vapour diffusion through a low-resistance, warm through-wall duct and is entirely non-mechanical. Moisture transmission is up to 1.4 litres per 24 hours under typical domestic conditions. The maximum served floor area is 10 m² per unit. Installation uses a Ø162mm Core Drilled Hole, with the main outer tube around 154 mm in diameter and a telescopic length from about 250 mm closed to about 410 mm open. The internal grille measures roughly 200 × 200 × 30 mm and contains an integrated flyscreen. The external cowl is available in several colours and is fixed with colour-matched screws, except the stainless variant which uses stainless steel screws to the cowl. The unit is silent in operation, requires no power and needs only occasional cleaning of the internal grille.

Q) How is the Passyfier Core 140 Dehumidifier Vent installed, step by step?

A) Mark a high-level position in the problem room and confirm clearance from services and structural elements. Drill a small pilot to the exterior to fix the centre, then core drill a Ø162mm hole with a slight outward fall so incidental moisture drains outside. Dry-fit the telescopic tube set and trim the outer tube if the wall is thinner than about 250 mm. Insert the supplied plastic wedge at the internal face if needed to maintain a minimum fall of around 6 mm. From outside, apply a continuous bead of silicone to the cowl flange, level the cowl over the opening and fix with the supplied colour-matched stainless screws. Slide the inner tube to suit the wall thickness, seal any gaps, then fix the internal grille housing square to the wall and push-fit the grille. Make good edges, clean down and verify a gentle moderation of airflow at the grille.

Q) On which wall types can the Passyfier Core 140 Dehumidifier Vent be used and what siting cautions apply?

A) The Passyfier Core 140 is suitable for solid masonry, cavity walls and timber-frame constructions, making it practical for both retrofit and new-build. In cavity walls, keep the duct continuous across the cavity and seal neatly around the annulus to avoid bypass draughts. In timber-frame, respect sheathing and weather-barrier details and seal carefully to maintain envelope integrity. Always position the vent high on the wall, keep the internal grille clear of curtains and furniture, and avoid siting too close to heat sources that could distort plastic components. Choose an exterior position with a clear path to atmosphere and, where possible, a degree of shelter from prevailing winds. Retain extractor fans in wet rooms because the Core 140 manages background humidity rather than short-term peaks.

Q) What maintenance does the Passyfier Core 140 Dehumidifier Vent require over time?

A) The Passyfier Core 140 has no motors, sensors or replaceable filters, so upkeep is minimal. Once or twice a year, wipe or lightly vacuum the internal grille and flyscreen to remove dust and cobwebs that can impede diffusion. After storms or heavy leaf fall, glance at the external cowl to confirm the opening is clear and the perimeter sealant remains sound. If redecorating, avoid painting over the grille slots or the cowl apertures. There is no electrical safety check because the unit has no power supply. Provided the grille remains unobstructed and the outward fall is maintained, the vent will continue to operate silently and effectively for many years with no further intervention.

Q) Are there any limitations to the Passyfier Core 140 Dehumidifier Vent I should consider before specifying it?

A) The Passyfier Core 140 provides passive background moisture control and is not a substitute for compliant extractor fans in kitchens and bathrooms. It must not be used to supply combustion air to gas, oil or solid-fuel appliances. It addresses airborne moisture rather than liquid water problems, so leaks, rising damp or penetrating damp must be remedied at source. Performance is reduced if the internal grille is obstructed by furnishings or heavy dust, if the tube lacks an outward fall, or if a low-level position is chosen where a high-level siting would have been feasible. In larger or very cluttered rooms, fit two units on opposing walls. Observing these constraints preserves comfort and ensures reliable dehumidification.

Q) What practical tips will maximise performance from a Passyfier Core 140 Dehumidifier Vent?

A) Mount the vent high so the top of the grille sits within about 300 mm of the ceiling, and keep the grille clear of curtains, pelmets and furniture. During installation, use the supplied wedge to set a slight outward fall and seal the cowl neatly to the façade to prevent bypass paths. Retain and use mechanical extract fans diligently in wet rooms, keeping doors closed during moisture-producing activities. Maintain steady background heat during colder months so indoor air can hold more moisture without reaching saturation on cold surfaces. In open-plan rooms or stubborn cases, add a second unit to the opposing wall for improved distribution. If the room previously had mould, clean with a fungicidal wash and redecorate so you start from clean, dry surfaces and can judge improvement accurately.

Q) How quickly should outcomes be visible after fitting a Passyfier Core 140 Dehumidifier Vent?

A) Most households notice that morning window streaming reduces within the first week of normal heating and ventilation patterns, particularly during colder spells when risk is highest. Black mould requires cleaning and redecorating after treatment, so visual improvement depends on aftercare as well as humidity reduction. Allow a full heating cycle or two to gauge the change while continuing good practice with extract fans and background heating. If results are slower than expected, check that the grille is unobstructed, the external cowl is clear, the tube has a slight outward fall and that short-term peaks in kitchens and bathrooms are being managed with extract. In larger or open-plan rooms, a second vent often accelerates stabilisation.

Q) Can the Passyfier Core 140 Dehumidifier Vent be supplied to match the exterior and will it look discreet indoors?

A) Yes. The external cowl is available in a range of colours to blend with common façades, and the exterior fixings are colour-matched for a tidy finish. The stainless variant uses stainless steel screws to the cowl. The circular core-drilled opening keeps the outside detail compact and easy to make good in brick, render or cladding. Indoors, the white 200 × 200 × 30 mm grille with integrated flyscreen presents a neutral appearance that suits most interiors and is simple to wipe clean. Because the unit is compact and installed near the ceiling, it is unobtrusive in day-to-day use, yet continues to work continuously at peak condensation times without any attention from occupants.

Q) How does the Passyfier Core 140 Dehumidifier Vent compare with trickle vents or leaving a window ajar?

A) Leaving a window ajar or relying on open vents admits bulk airflow that can cause uncomfortable draughts and heat loss, encouraging occupants to close or block the opening. The Passyfier Core 140 is shaped to resist free through-draughts while allowing moisture vapour to diffuse out, so it operates comfortably year-round and continues working overnight when condensation risk peaks. It also maintains a warm, lined pathway through the wall, limiting heat loss compared with uncontrolled openings. In practical terms this improves compliance, keeps background humidity more stable and reduces mould risk without compromising comfort, security or energy use. Combined with good use of extract fans in wet rooms, it is a balanced, low-energy strategy for healthier indoor conditions.

Q) Is the Passyfier Core 140 Dehumidifier Vent suitable for retrofit and new-build projects and what does a typical install look like?

A) The Passyfier Core 140 is designed for rapid retrofit and straightforward inclusion in new-build. A Ø162mm Core Bit produces a neat circular opening, the telescopic tube set adjusts to suit common wall thicknesses between about 250 mm and 410 mm, and the supplied wedge helps set the correct outward fall. The external cowl is sealed and fixed with colour-matched stainless screws, and the interior is finished with a crisp white grille that is easy to keep clean. The method suits solid masonry, cavity walls and timber-frame, and produces a discreet, durable detail that works continuously with zero running cost. When paired with compliant extract in kitchens and bathrooms and sensible occupant guidance, it offers a robust, low-maintenance route to long-term moisture control in modern airtight homes.

Technical Data Sheet