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Honeywell HPA304 Allergen Plus HEPA Air Purifier, White

Rooms up to about 465 sq ft where simple manual controls suit

Honeywell's HPA304 runs three Type R True HEPA filters behind a Type A odour-reducing pre-filter. It is AHAM Verified for 465 square feet. Plan on three HEPA filters a year and a pre-filter every three months, none washable, with manual cleaning levels, a timer and a five-year warranty.

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Published specifications

  • Honeywell: AHAM Verified 465 sq ft, air filtered every 12.5 minutes
  • Manual: HRF-R3 HEPA pack every 12 months
  • Manual: HRF-AP1 pre-filter every 3 months
  • Manual: three cleaning levels, Turbo, 2/4/8 h timer, dimmer
  • Honeywell: 22.3 H x 20.0 L x 10.8 W in
  • Manual and Honeywell: five-year limited warranty

Fit and limits

Strengths

  • AHAM Verified room size published by the maker
  • Five-year limited warranty
  • Simple controls with timer and dimmer

Caveats

  • Three HEPA filters to replace each year
  • Pre-filter replaced every 3 months; nothing washable
  • Listing model field HPA104WMP does not match HPA304

Which Honeywell this is

Honeywell's product page lists this as the HPA304 in white, its HEPA air purifier for extra-large rooms. The manual shipped with it covers four series at once, and for the HPA300 series it describes a two-stage system: a pre-filter in front of three True HEPA filters.

The Amazon details table lists model number HPA104WMP and part number HPA304V2, with compatible models HPA300 and HPA304 and manufacturer Kaz. The HPA104 code does not match the title or Honeywell's page, so check the label on the unit when it arrives.

Room size: 465 square feet verified

Honeywell's page says the HPA304 is independently tested and AHAM Verified to circulate and filter the air every 12.5 minutes in a 465 square foot room, which is 4.8 changes per hour. The 2,250 square foot figure in the Amazon title is for one air change per hour.

Neither the page nor the manual pages we read prints the CADR numbers themselves, so the 465 square foot figure is the only sizing number Honeywell gives. The Amazon table lists 80 watts and 17 pounds; Honeywell's page does not state either.

Placement from the manual

The manual asks for a firm, level surface with the front of the unit facing away from the nearest wall or furniture. It does not give a clearance distance in inches, so leave open space in front of the grille rather than pushing it into a corner.

It should be used upright, indoors, away from bathrooms, laundry areas and other damp places, and near its outlet without an extension cord. Honeywell lists the unit at 22.3 inches high, 20.0 inches long and 10.8 inches wide.

Filter costs are driven by three HEPA filters

The HPA300 series takes three Type R True HEPA filters, listed as HRF-R3 and replaced every 12 months, and one Type A pre-filter, HRF-AP1, replaced every 3 months. Honeywell's page repeats both intervals. The manual lists an alternative pre-filter, HRF-APP1, at the same 3-month interval.

None of the filters is washable. The manual describes a filter reset after replacement, and asks for the unit to be cleaned with a dry cloth every three months. The manual also covers storage longer than 30 days, so read that page before putting it away for a season.

Controls and settings

The manual describes three cleaning levels plus Turbo, an auto-off timer with 2, 4 or 8 hour settings and a dimmer for the display. The manual pages we read describe no auto mode or air-quality sensor, so you set the speed yourself.

The manual carries an ENERGY STAR note. Because the pre-filter is due every three months and the three HEPA filters yearly, the running cost is set by filters rather than electricity; the Amazon table's 80 watts is the only power figure we found.

Five-year limited warranty

The manual and Honeywell's page both give a five-year limited warranty, with Kaz named in the manual. The filters are covered only for material or workmanship defects, not for wearing out, so the three-monthly pre-filter and yearly HEPA changes are your cost.

The manual warns that opening the motor housing may void the warranty, so leave any internal fault to the warranty process. Keep proof of purchase, and read the manual's warranty page for the full conditions, which we did not record in detail.

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Primary sources

  1. Honeywell Plugged In product page for the Allergen Plus HEPA air purifier HPA304
  2. Honeywell HPA090, HPA100, HPA200 and HPA300 series owner's manual supplied with the listing

Primary sources checked .

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