Compare Nuaire Drimaster and Kair PIV units – standard and heater versions
Condensation
Water droplets building up on windows each morning, especially during colder months and winter periods.
Mould Growth
Black mould slowly appearing on walls, ceilings, or in room corners and becoming harder to control.
Stale Air
A musty, stale feeling in the home that never fully goes away, even after regularly airing rooms.
Poor Airflow
Extractor fans in bathrooms and kitchens that struggle to remove moisture, steam, and lingering humidity.
PIV may not be suitable for properties with active leaks or severe penetrating damp and building defects.
Understanding Condensation, Mould & Indoor Moisture
Condensation and mould are usually caused by everyday moisture building up inside the home, especially where ventilation is limited. Understanding where this moisture comes from, how to spot early warning signs, and why common quick fixes don’t last helps explain why long-term ventilation solutions are often needed.
Understanding Condensation, Mould & Indoor Moisture
Condensation and mould are usually caused by everyday moisture building up inside the home, especially where ventilation is limited. Understanding where this moisture comes from, how to spot early warning signs, and why common quick fixes don’t last helps explain why long-term ventilation solutions are often needed.
PIV gently supplies fresh, filtered air into the home to reduce condensation, mould, and stale air.
In many homes, a standard PIV unit is more than sufficient, with heater versions mainly recommended where loft temperatures drop very low in winter.
A standard PIV unit uses gently filtered air that is already tempered by the loft space, making it suitable for most homes and the most energy-efficient option.
Best suited for:
Homes with reasonable loft temperatures, well-insulated properties, and customers looking for the lowest running costs.
A heated PIV unit includes a 400 wattage heater that slightly warms the incoming air, improving comfort in colder lofts or poorly insulated homes.
Best suited for:
Properties with cold loft spaces, older housing, or occupants who are sensitive to cooler incoming air.
Nuaire and Kair PIV units are designed to achieve the same result by reducing condensation, mould, and stale air through continuous positive ventilation. Both ranges are available in standard and heater versions and offer similar airflow performance, filtration, and quiet operation for residential use. The key difference is branding, with Kair units providing a cost-effective alternative that delivers comparable performance and reliability without the brand premium.
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Both ranges are available in standard and heater versions, offering similar airflow performance and filtration, with the main difference being branding and price.
Consumption: 1.6W(min) 17W(max)
Up to 422W with heater at full load.
Fuse size: 3 Amp
HCS (Ceiling Control) models have the controls built into the ceiling diffuser, allowing easy adjustment from the hallway without needing loft access.
In most cases, these settings are only adjusted during installation or when adjusting speed or temperature for summer and winter modes.
4 Way Heater and Boost
Humidity Sensor
CO2 Sensor
7 year warranty: 1 year parts and labour, remaining 6 years parts only (UK and Ireland only).
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Drimaster LC
Original price was: £389.40.£267.00Current price is: £267.00.Loft Fitted Yes Integral Heater No Airflow (l/s) 10–60 Power Usage 1.6W – 17W Unit Controls Via Loft Sensors No Warranty 5 Years -
Kair LC
Original price was: £389.40.£257.00Current price is: £257.00.Loft Fitted Yes Integral Heater No Airflow (l/s) 10–60 Power Usage 1.6W – 17W Unit Controls Via Loft Sensors No Warranty 5 Years -
Drimaster HCS
Original price was: £429.49.£405.00Current price is: £405.00.Loft Fitted Yes Integral Heater Yes (400W) Airflow (l/s) 10–60 Power Usage 1.6W – 17W Unit Controls Hallway Sensors No Warranty 7 Years -
Kair HCS
Original price was: £533.28.£397.00Current price is: £397.00.Loft Fitted Yes Integral Heater Yes (400W) Airflow (l/s) 10–60 Power Usage 1.6W – 17W Unit Controls Hallway Sensors No Warranty 7 Years -
Drimaster Heat + 4 Way Switch
Original price was: £650.00.£580.00Current price is: £580.00.Loft Fitted Yes Integral Heater Yes (400W) Airflow (l/s) 10–60 Power Usage 1.6W – 17W Unit Controls Hallway Sensors Yes Warranty 7 Years
5 stars from us!
We live in a 3-bed bungalow and always had condensation on the windows in colder months, even with new double glazing and trickle vents. Humidity was usually over 70% unless we used a dehumidifier every night. A family member suggested trying a PIV unit. We weren’t sure it would help, but for around £300, we gave it a go.
Installation was easy since we already had a socket in the loft. I mounted it straight to the rafters, thinking I could move it later if it was noisy but it’s been fine. We started on setting 3, but now run it at 1. There’s a small draft under the hallway vent, but we haven’t noticed any rise in heating costs or felt colder.
The results were quick within 24 hours, the window condensation disappeared. Our humidity dropped to under 40%, so we lowered the setting. Now it stays around 45–50% and the unit is very quiet. At first, we did notice a musty smell as it cleared out old loft air, but that went away after a few weeks. I added an air freshener near it, which helped.
This might not fix every damp issue, but for us it’s been brilliant and totally worth the money.
Great product and has done well for the last 4years! Just about to change the filters for the first time! Simple efficient condensation removal with easy installation – just bought a second for our rental house!
Moved into our bungalow in 1989 and found we got terrible condensation. After a couple of years trying various solutions without much success we heard about Nuaire and had one of these earlier models installed. A basic model with just 2 settings but for 25+ years the house virtually condensation free (only if I forgot to go into loft and put it on higher setting for winter) After all these trouble free years the fan started making noises and I switched it off.The condensation returned! Got a quote from Envirovent for installation of a similar unit for £1300! Fortunately then found this site and product. Just fitted it and so easy, especially as it just replaced the existing unit. Lighter than the earlier model and now with 5 settings that can be easily reached on the difusser on the hallway ceiling. Hershoping for another trouble free 25 years!
Looks and works just like a Nuaire unit.
What I like:
We had serious condensation problems in our small home—wet windows all year round, even in summer. This unit fixed it within a week. The air feels fresher, the windows stay clear, the bathroom mirror doesn’t steam up as much, and the house seems to warm up quicker now.
What I don’t like:
This is the basic model (KAIKWH150-ECO-LC) with loft-only controls and no heater. It’s basically a plastic box with a fan that pushes filtered air into the house at speeds 1 to 6. It works well, but at £360, it feels overpriced—half that would seem more reasonable. Recommend to get the heater version instead.
We had loads of condensation and black mould, but since fitting this, it’s all gone. Wish we’d installed it sooner absolutely brilliant!
This was delivered next working day…I fitted the system myself and within 2 weeks has cured our condensation problems.. Damp areas on walls and windows have gone, internal doors fit better again, laminate flooring had become mousey when you walked on it, now back to normal. Also air quality is much better, stale food smells do not linger..We have an open plan living area so this is really helpful….In fact It is only when you have removed the issues that you realise how good this system is…Great value for money too…I highly recommend this….
Had this installed now for Four years, we suffered condensation really bad, but within a week of installation all window were bone dry and still are to this day 03.12.25.
Worth every penny, better than the dehumidifiers we were using.(Good ones ,not the cheap type).
Hi, this is an excellent product and well worth the money the fitting is easy and took less than an hour. Okay the house was suffering from mould and condensation and although we had already had surveys for damp and condensation (they wanted over 1000 GBP to fix the problem) we opted to buy and install Nuaire PIV and used a qualified electrician to fit it. Since we’ve had it fitted the mould has gone and the condensation is no more . The air feels fresher you hear no noise from the unit you do get a slight draught only slightly noticeable it’s 5 Stars from us Great service and delivery from i-sells.co.uk
Ted is a star , fountain of knowledge , WHY , we learnt more about ventilation in the long phone call , than with any tradesman or U tube video etc , We went through all the reasons for condensation in our bungalow & Ted gave so many options , and we ordered equipment , and will be making other changes .We placed the order @ 11.00am on Monday , Parcel Force deliveried @ 10.15 am ,Manchester area , superb service .Thank you Ted you are credit to your Company
It was easy to install and less than 24 hours later all the condensation was gone!
View Recommended PIV Units
You’ll be taken to the product page to select options and complete checkout securely.
Original price was: £389.40.£257.00Current price is: £257.00.
Non heater version.
Original price was: £429.49.£405.00Current price is: £405.00.
400w Integral Heater
Original price was: £533.28.£397.00Current price is: £397.00.
400w Integral Heater
Original price was: £650.00.£580.00Current price is: £580.00.
+ 4 Way Switch Bundle
A clear walkthrough showing how a PIV unit is installed, what’s involved, and what to expect during fitting.
We specialise in ventilation and air quality solutions, supplying trusted PIV systems to homeowners, landlords, and installers across the UK.
View Recommended PIV Units
You’ll be taken to the product page to select options and complete checkout securely.
Original price was: £389.40.£257.00Current price is: £257.00.
Non heater version.
Original price was: £429.49.£405.00Current price is: £405.00.
400w Integral Heater
Original price was: £533.28.£397.00Current price is: £397.00.
400w Integral Heater
Original price was: £650.00.£580.00Current price is: £580.00.
+ 4 Way Switch Bundle
Got questions? Here are some of the most common things customers ask about PIV’s.
A PIV system is designed to supply fresh air gently at a low, continuous rate, which helps balance indoor air without causing noticeable cold draughts. The incoming air is typically tempered by the loft space, and heater models are available for added comfort in colder conditions or poorly insulated homes.
To run the unit, electrical consumption would (typically) be about 1p per day. However, it should be remembered that the unit is making use of heat at ceiling level which would otherwise be lost.
The unit will switch itself into standby mode when temperatures reach such that condensation would not occur within your home eg. during the summertime.
Electrical details
Voltage: 230V 1ph 50Hz
Consumption: 1.6W(min) 17W(max) Up to 422W with heater at full load.
Fuse size: 3 Amp
A PIV system is designed to supply filtered fresh air into the home, not circulate odours from the loft space. If a loft has a musty smell, this is usually due to poor ventilation in the loft itself, and the PIV unit filters the incoming air before it enters the property.
No, doors do not need to be kept open, but a small gap of around 10mm (1cm) under internal doors helps fresh, filtered air circulate effectively throughout the home.
The supplied ducting extends up to 2 metres when fully extended and cannot be extended further, as increasing the duct length may affect the unit’s performance.
To maintain the optimum performance of your PIV unit, the filter must be kept clean and clear.
The cleaning or replacement of the filters is required every 5 years.
During installation your unit will have been set to run continuously at a level that will adequately ventilate your home.
As house sizes and occupancy levels vary, your PIV unit has 6 speed controls which can be adjusted to suit your home.
LC (Loft Control) models have their controls located on the unit itself, which is installed in the loft.
HCS (Ceiling Control) models have the controls built into the ceiling diffuser, allowing easy adjustment from the hallway without needing loft access.
Installing the Drimaster involves cutting a hole in your ceiling, working in the loft space, securing ducting, and wiring the unit to the mains. An electrician or installer can do this safely and neatly in a few hours. Once fitted, it runs quietly in the background with no maintenance needed.
✅ Typical installation time: 1-2 hours
💷 Estimated cost: £150-£250+ depending on your location and loft access.
Once installed, the unit runs quietly in the background and requires no ongoing maintenance apart from replacing filters every 5 years.