Choosing a purifier
How to choose an air purifier for your home
Room size, filter composition and regular filter replacement decide the result more than the number of buttons.
Updated:
The short answer
Compare the stated room rating: WAP-35 up to 35 m² and WAP-50 up to 80 m², allowing for ceiling height and connected spaces. Check the combined pre-filter, activated carbon and HEPA filter, the replacement requirements and everyday noise. Carbon can reduce some odours; HEPA captures particles. Neither means every pollutant is removed.
Three filtration stages
The pre-filter traps larger particles such as hair and pet fur. Activated carbon can reduce some odours and gases; HEPA captures airborne particles such as fine dust and pollen. No filter removes every pollutant, and filtration does not replace source control and ventilation. WAP-50 has an H13 HEPA filter.
Coverage and performance
The coverage figure is stated in the manual: 35 m² for WAP-35 and 80 m² for WAP-50. Open doors or a high ceiling increase the air volume, so choose a model with headroom rather than one at its limit.
Sensor and automatic mode
WAP-50 has a PM2.5 sensor, a colour indicator and automatic speed adjustment in AUTO mode. Its response depends on the particles the sensor detects. A lower speed or a favourable indicator reading does not mean the air is free of all pollutants: the PM2.5 sensor does not measure every gas.
Noise, night mode and timer
For a bedroom, compare noise at the speed you will actually use. WAP-50 has a night mode with the display off, a 1–24 hour timer and four power levels plus Turbo. Night mode is not a promise of silence; check the exact model's specifications and controls.
Filter replacement and care
Unplug the purifier before opening it, even if removal of the cover stops the fan. Replace the combined filter and clean the pre-filter only as the manual allows; do not wash HEPA unless the exact model's manual explicitly permits it. Refit the cover and reset the filter counter according to the instructions.
Purifier checklist
- Measure the room; the model's coverage must be at least as large.
- Check the filter composition: coarse layer, activated carbon, HEPA.
- For a bedroom check the night mode and the noise at the lowest speed.
- Plan a spot with clear space around the unit, away from heat sources.
- Find out the price and availability of the replacement filter before buying.
Common mistakes
- Buying a model at its coverage limit for a room with open doors.
- Running the purifier for an hour instead of regularly.
- Ignoring the filter indicator or washing the HEPA filter with water.
- Placing the unit hard against a wall or furniture.
Models to compare
WetAir manuals and support
Check the exact model requirements
If the filter indicator will not reset or the unit ignores the buttons after a filter change, check the filter fitting against the diagram in the manual and contact WetAir service.
Sources and verification
Filter composition, coverage figures, the PM2.5 sensor, timer and maintenance rules come from the WetAir WAP-50 and WAP-35 manuals.
Frequently asked questions
Does a purifier help with odours?
The activated-carbon layer may reduce some odours, depending on the substance and filter condition. HEPA captures particles, not gases. Remove the source of the odour and ventilate when appropriate rather than relying on filtration alone.
How often should the filter be replaced?
Follow the filter indicator and the model's manual; in very dusty rooms the interval shortens.
Can the purifier run around the clock?
Yes, the units are designed for long running; at night use the night mode or the lowest speed.