Right Size Air product guide
KNKA APH4000 Air Purifier, White
Rooms around 350 sq ft where an auto and pet mode matter
KNKA's APH4000 pulls air through front and back filter cartridges and adds a PM2.5 sensor, auto, ECO, pet and sleep modes, and a pop-out aroma box. KNKA lists a 226 CFM smoke CADR and 4.8 air changes an hour in 350 square feet. Plan on two filters every 3 to 6 months.
Listing checked . Confirm the model, included parts and availability before ordering.
Published specifications
- KNKA page: CADR smoke/dust 226 CFM, pollen 244 CFM
- KNKA page: 4.8 ACH in 350 sq ft; 1 ACH in 1,695
- Manual: two composite filters, front and back
- KNKA page: replace filters every 3 to 6 months
- Manual: 12.36 x 8.15 x 17.09 in, 9.68 lb, 45 W
- Listing: two-year warranty
Fit and limits
Strengths
- Dual intakes and two filter cartridges
- Auto, ECO, pet and sleep modes with a PM2.5 display
- Filter indicator turns red at 5 per cent remaining
Caveats
- Two filters every 3 to 6 months
- Manual gives conflicting washing guidance
- No clearance distance or warranty terms in the manual
Two filter cartridges, front and back
KNKA's page describes dual front and back three-stage filter cartridges. The manual's package list holds the unit, two filters, a power adapter, the manual and four aroma pads, and it lists an essential-oil fragrance box among the features.
The manual gives the unit as 12.36 by 8.15 by 17.09 inches and 9.68 pounds, with support legs. It runs from a 24-volt, 2-amp adapter with a rated power of 45 watts and standby power of 2 watts or less. KNKA's page asks for genuine filters.
Room size: 350 square feet for frequent changes
KNKA's product page gives CADR figures of 226 and 244 CFM, and the Amazon table labels them smoke and dust 226, pollen 244. KNKA says the unit refreshes the air 4.8 times per hour in rooms up to 350 square feet, and that the 1,695 square foot figure is one refresh per hour at about 45 per cent purification efficiency.
The Amazon title mentions AHAM verification, but KNKA's page and the manual we read do not repeat that claim or name a test standard. Plan around 350 square feet if you want several air changes an hour.
A built-in essential oil box
Unusually, the APH4000 has an essential-oil fragrance box, and the package includes four aroma pads. The manual describes how to use it, so follow that page rather than improvising; the box and pads are listed among the package contents and product features.
If you do not want scent near the filters, simply leave the pad dry. The manual pages we read do not say whether oil affects filter life, and we make no claim either way. Read the manual's safety page before using oils.
Filter life and cleaning
KNKA's page recommends replacing the filters every 3 to 6 months. The manual says the filter indicator turns red at 5 per cent or less remaining, and to hold it for three seconds to reset after fitting new filters. Genuine KNKA filters are requested.
The manual says to vacuum the filter about once a month and not to wash the composite filter; it separately describes the pre-filter as washable with water, which conflicts. It also asks for the body to be cleaned monthly.
Modes and sensor
The manual lists Manual, Auto, Sleep, ECO and Pet modes, four fan speeds, a 1 to 12 hour timer and a PM2.5 display. KNKA's page says Pet mode runs for 30 minutes and lists an ECO mode. What each mode does in detail is in the manual.
The manual gives no clearance distance, so leave open space at both the front and back intakes. KNKA's page does not print an AHAM statement, so the verification claim in the Amazon title rests on the listing alone.
Warranty
The Amazon listing gives a two-year warranty. KNKA's product page says its products carry a limited warranty as set out in each product's warranty documentation, without stating a length on the page we read.
The manual pages we read do not include warranty terms, so confirm coverage length and conditions with KNKA and keep proof of purchase. The two-year figure appears only in the Amazon listing, so do not count on it until KNKA confirms.
Check the current listing
Confirm the model, included parts and availability before ordering.
Primary sources
Primary sources checked .
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