Mitsubishi Lossnay Filters

A well-matched F7/ePM1 filter is designed to fit the same housing as the standard M5 filter, so any change in airflow resistance is generally small and not noticeable in day-to-day use. If you do notice a drop in airflow or an increase in fan noise after upgrading, it's usually a sign the filter needs checking sooner rather than the upgrade itself being unsuitable.

Filter compatibility generally holds within the same Lossnay series and housing generation, but Mitsubishi has updated internal filter dimensions across some model refreshes even under a similar product name. Matching by your exact model number, or measuring the filter directly, is the safest way to confirm fit across generations.

The standard 3–6 month interval applies to Lossnay units, though the built-in maintenance indicator on many models will flag when airflow has dropped due to filter loading. Treat that indicator as a helpful reminder rather than the sole basis for replacement timing, especially in higher-pollution areas.

Most residential Lossnay units offer two filtration levels:

• M5-class filter as standard
• F7/ePM1 available as a supply-side upgrade, for improved allergen and fine dust filtration

Both are compatible with the same filter housing.

Lossnay refers to Mitsubishi Electric's heat exchange element, not the filter itself, so Lossnay-branded units use conventional M5/F7-class filters like other MVHR systems — the name simply identifies the ventilation product line to look for when ordering. The unit's model number, found on the casing label, confirms the exact filter size.