Brands › Lennox › ML196UHE(K)
Lennox ML196UH045XE36BK furnace filter size
This furnace takes a 16 x 25 x 1 filter (side or bottom return).
Every filter option for this model
| Where return air enters | Filter size (inches) | How many |
|---|---|---|
| side | 16 x 25 x 1 | 1 |
| bottom | 16 x 25 x 1 | 1 |
Where the filter goes
external, field-provided; doc: "This unit is not equipped with a filter or rack. A field-provided high velocity rated filter is required for the unit to operate properly."
The maker does not ship a filter with this furnace. The size above is the maker's recommended size at the furnace; if your home has a filter grille in a wall or ceiling, that grille sets the size instead.
How often to change it
General guidance, not from the maker's table: 1-inch filters every 1 to 3 months; 4- and 5-inch filters every 6 to 12 months. Change sooner with pets, smoking or construction dust.
About this model
| Cabinet width | 17.5 in. |
|---|---|
| Airflow direction | upflow/horizontal |
| Heat input | 44,000 BTU/hr |
| Efficiency (AFUE) | 96% |
| Model number note | Lennox adds -01/-02 etc. revision suffixes on nameplate; K = R-454B refrigerant-detection version |
How to read a Lennox model number
Source
- ML196UHEK Installation Instructions 508569-01 (05/2026) (installation manual, page 13): document. Read 2026-11-03.
- ML196UHEK Unit Information 100165 (service manual, page 53): document. Read 2026-11-03.
Check that the model number on your furnace label matches, and compare with the size printed on your old filter. If they differ, go by the filter that fits your rack.