How to Replace the Charcoal Filter on a Frigidaire FFMV1645TS Microwave — Step-by-Step Instructions
Step-by-step instructions for the Frigidaire FFMV1645TS (over-the-range microwave, 1.6 cu ft). Parts and access points can differ slightly by production year — the steps below cover the common layout for this platform, and the model notes flag its quirks.
This filter sits behind the vent grille at the top front of the microwave. Unplug the unit before removing the grille. Never remove the outer metal cabinet of a microwave. The high-voltage capacitor inside stores a charge that can kill you, and it holds that charge after the unit is unplugged. Every step in this guide stays outside the cabinet or inside the cooking cavity — if a repair needs the case off, it is a job for a technician. Removing the vent grille is normal owner maintenance and does not expose the cabinet interior.
Tools
- Screwdriver
- Step stool
Parts
- Model-specific charcoal / recirculating filter $15–$50
Step by step
-
1 Check whether you actually need one
Charcoal filters are only fitted to recirculating installations — units that blow air back into the room rather than outside through a duct. If your microwave vents outdoors, there is no charcoal filter to change.
-
2 Unplug the microwave
The outlet is usually in the cabinet directly above the unit.
-
3 Remove the vent grille
Two screws along the top edge, sometimes hidden inside the cabinet above. Undo them, then slide the grille up and out — most hook downward into slots rather than lifting straight off.
-
4 Slide out the old filter
It sits in a slot behind the grille. Note the orientation as it comes out; some have an airflow arrow printed on the frame.
-
5 Fit the new filter
Slide it in the same way round. It should sit flat with no gaps at the edges — a filter that does not seat lets air bypass it entirely.
-
6 Refit the grille and plug back in
Hook the grille into its slots first, then replace the screws. Run the fan and confirm it sounds normal.
-
7 Note the date
Charcoal filters last roughly six to twelve months and cannot be washed — unlike the metal grease filters, these genuinely have to be replaced.
Frigidaire FFMV1645TS notes & error codes
In rental property these are almost always installed recirculating rather than ducted outside, which means a charcoal filter behind the top grille that has never been changed. Check for one before diagnosing weak venting as a blower fault.
| Code | What it means |
|---|---|
| F1 | Control or touch panel fault |
| F3 | Shorted key |
| door | Door sensing fault |
Full details for this machine — common problems, causes, and costs — are in the Frigidaire FFMV1645TS repair guide. The general version of these instructions is here.
If cooking smells persist with a new filter, the unit may be ducted incorrectly or the damper may be stuck. Both are worth a professional look, especially if the microwave was recently installed. If you'd rather skip it entirely, find a microwave repair pro near you →
What this repair costs professionally
Sources
Where the safety, regulatory and warranty claims on this page come from. Repair costs are our own figures based on Arizona market rates and OEM parts pricing.
- Microwave Ovens — Radiation-Emitting Products U.S. Food & Drug Administration The federal requirement for two independent door interlocks plus a monitoring system, and the 21 CFR 1030.10 leakage limit — why an interlock must never be bypassed.
Find a microwave repair pro near you.
Browse verified independent appliance repair companies by city — ratings, hours, and phone numbers, no middleman.