Fresh air, heat stays in. You pick the brand.
We only install Zehnder (Q350, Q450, Q600) and Renson Flux+ (Compact, Wall, Flat). Photos, prices and dimensions — everything before the quote.
Two brands, deliberately
Both top class. The details decide.
The overlap
This is what they both do.
The differences
Side by side, honestly.
| Feature | Zehnder ComfoAir Q | Renson Flux+ |
|---|---|---|
| Heat recovery | up to 92.3% | up to 91% |
| Capacity | 350–600 m³/h | 225–650 m³/h · Wall, Flat & Compact |
| Noise | whisper-quiet, even at full speed | whisper-quiet at comfort speed |
| Weight | 50 kg | 21–29 kg |
| Controls | display on the unit · app optional (ComfoConnect PRO, € 265 excl. VAT) | app built in (no display) |
| Connections | top connection | top ánd side connection |
| Moisture recovery | optional (ERV version) | optional (ERV version) |
| Air quality sensors | humidity standard · CO₂ optional | humidity + CO₂ + odour built in |
| Summer cooling | ComfoClime or ComfoPost | ComfoPost |
| Entry model | ComfoAir E (manual controls) | Flux Go (manual controls) |
| Filters | G4 · F7 optional Filter sets: 400502012 (G4/G4) · 400502013 (G4/F7) · 400102099 (anti-pollen M5/G4) | G4 · ePM1/Carbon optional Filter kits (Classic/Urban): Wall 34636/34637 · Compact 37371/37370 · Flat 17793/76015046 |
Heat recovery
Zehnder
up to 92.3%
Renson
up to 91%
Capacity
Zehnder
350–600 m³/h
Renson
225–650 m³/h · Wall, Flat & Compact
Noise
Zehnder
whisper-quiet, even at full speed
Renson
whisper-quiet at comfort speed
Weight
Zehnder
50 kg
Renson
21–29 kg
Controls
Zehnder
display on the unit · app optional (ComfoConnect PRO, € 265 excl. VAT)
Renson
app built in (no display)
Connections
Zehnder
top connection
Renson
top ánd side connection
Moisture recovery
Zehnder
optional (ERV version)
Renson
optional (ERV version)
Air quality sensors
Zehnder
humidity standard · CO₂ optional
Renson
humidity + CO₂ + odour built in
Summer cooling
Zehnder
ComfoClime or ComfoPost
Renson
ComfoPost
Entry model
Zehnder
ComfoAir E (manual controls)
Renson
Flux Go (manual controls)
Filters
Zehnder
G4 · F7 optional Filter sets: 400502012 (G4/G4) · 400502013 (G4/F7) · 400102099 (anti-pollen M5/G4)
Renson
G4 · ePM1/Carbon optional Filter kits (Classic/Urban): Wall 34636/34637 · Compact 37371/37370 · Flat 17793/76015046
Figures from the official Zehnder and Renson datasheets (heat recovery per EN 13141-7).
Line-up · Zehnder
ComfoAir Q — three sizes, one quality.
ComfoAir Q350
- Airflowup to 350 m³/h
- Weight50 kg
- ConnectionØ160/190
- CoolingComfoClime 24
unit from € 1.895 excl. VAT
Watch video
ComfoAir Q450
- Airflowup to 450 m³/h
- Weight50 kg
- ConnectionØ180/200
- CoolingComfoClime 36
unit from € 2.185 excl. VAT
Watch video
ComfoAir Q600
- Airflowup to 600 m³/h
- Weight50 kg
- ConnectionØ180/200
- CoolingComfoClime 36
unit from € 2.300 excl. VAT
Watch videoComfoClime cooling is plug-and-play per model: the 24 on the Q350, the 36 on the Q450 and Q600.
Options on the ComfoAir Q
One unit, multiple options.
ComfoClime 24 / 36
Plug-and-play top cooling — the 24 on the Q350, the 36 on the Q450 & Q600. Watch video
ComfoPost
Duct cooling on the supply air — works with any balanced-ventilation unit.
ComfoFond-L Q
Ground heat exchanger — pre-heats in winter, pre-cools in summer.
Line-up · Renson
Flux+ — a size for every space.
Flux+ Compact
- 275 & 350 m³/h
- only 55 cm tall · 21 kg
- wall-mounted
unit from € 1.694 excl. VAT
Watch video
Flux+ Wall
- 475 & 650 m³/h
- 29 kg
- wall-mounted · left/right adjustable
unit from € 2.631 excl. VAT
Watch video
Flux+ Flat
- 225 / 275 / 370 m³/h
- HRV or ERV version
- ceiling ór wall
unit from € 1.999 excl. VAT
Watch videoAll Flux+ units: humidity, CO₂ and odour sensors built in, app control and 100% automatic summer bypass.
In practice
A mounting spot in every home.
Flux+ Wall
On the wall in the utility room, garage or attic — duct entry from top ór side.
Flux+ Wall Compact
Only 55 cm tall and 21 kg — fits in a cupboard or above the washing machine.
Flux+ Flat
Flat against the ceiling — ideal for apartments and renovations without a utility room.
Photo: Renson installation wall — Flat on the ceiling, Wall on the wall.
Control? Simply on your phone.
These are real screenshots from installations we did. Airflow, CO2, humidity and temperature — you see and control everything from the couch.
Fully automatic on sensors — the app is your window on the indoor climate.
App control via ComfoConnect PRO — see heat recovery happen in real time.
Decision aid
Choose with confidence.
Choose Zehnder ComfoAir Q if…
- you want the quietest unit — even at full speed
- you want a display on the unit itself
- you want active summer cooling (ComfoClime heat pump)
- you want the most proven choice (market leader)
Choose Renson Flux+ if…
- space is tight — Wall, Flat ór Compact (55 cm), also side connection
- you want moisture recovery as an option (ERV version)
- you want smart control on CO₂ ánd odour as standard
- you want the newest generation (VSK+E Award 2026)
Also cool through your HRV?
ComfoClime & ComfoPost — first certified installer in NL.
Know your pick — or want us to think along?
Request a quote or call us. Reply within 24 hours.
WTW expert
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Official dealer Zehnder · Renson·First in NL with ComfoClime-certificate
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