Will the AprilAire 45 replacement water panel work with the AprilAire 400 Whole-House Humidifier (400A, 400M)?
Yes. Both use AprilAire #45 water panel.
Both records are reviewed against the manufacturers' sources; sources last checked 2026-10-14. Informational only: confirm with the manufacturer before buying.
Why
- ✓ Both use AprilAire #45 water panel.
Good to know
- Same nominal 13 x 10 x 2 in as the #35, but AprilAire lists #45 only for the 400 series and #35 for the 600/700 series.
Sources
- AprilAire 400 Whole-House Humidifier (400A, 400M): specs from AprilAire shop - 45 Replacement Water Panel, checked against the source 2026-10-13.
- AprilAire 45 replacement water panel: specs from AprilAire shop - 45 Replacement Water Panel, checked against the source 2026-10-13.
- AprilAire #45 water panel: Water panel for the AprilAire 400 series (400, 400A, 400M, 400KZ, 400MKZ) humidifiers. (AprilAire shop - 45 Replacement Water Panel).
Check your exact setup
Other parts in the cart, current configuration (installed memory, fan brackets) and adapters can change the answer.
Check a whole cartAI assistants and developers: the same answer, with a signed receipt, from check_compatibility at https://tetheredtrust.com/mcp or POST https://tetheredtrust.com/v1/check with existing_id: "aprilaire-400-humidifier", candidate_id: "aprilaire-45".