Wolf drawer microwaves (MD24 / MD30 Transitional and Contemporary): quick sheet

Covers: Wolf built-in drawer microwaves: 30-inch MD30TE/S (Transitional, also listed as MD30TES), 24-inch MD24TE/S, and Contemporary / Professional variants with MD24 and MD30 prefixes; flush or standard installation kits change the trim only. Wolf countertop, built-in door microwaves and speed ovens are different products. Read the rating label (open the drawer; label on the frame) for the model and serial.

Cross-checkedBrands: Wolf6 components

A 120 V, 15 A under-counter microwave whose drawer is opened and closed by a motor: the owner presses OPEN or CLOSE and should not push or pull the drawer except in an emergency. Wolf lists 950 W cooking power, 1.2 cu. ft. (MD30), ten power levels and sensor cooking. Most calls are drawer mechanics (binding from oversized mounting screws, an unlevel install, debris in the slides, a drawer motor or position switch fault) and dead controls (tripped GFCI, control lock, blown internal fuse, failed control board). The magnetron section is a high-voltage microwave circuit: diagnosis inside the case is caution-only work.

Safety first

Microwave high-voltage section: the capacitor can hold a lethal charge after unplugging. Discharge and verify 0 V before touching anything inside the case (caution).
Never run the microwave with the case open or interlocks bypassed.
The drawer motor can move unexpectedly: keep hands clear of the drawer path when power is on.

How it works

Drawer drive: a motor drives the drawer along its slides; position / sensing switches tell the control when the drawer is fully open or closed. Wolf lists installation issues, power failure, position or sensing switch, drawer motor, control unit and the slides or rails as the causes when the drawer will not open or close.

Door interlock: when the drawer is closed, interlock switches let the control energize the high-voltage section; an open or misaligned switch stops cooking for safety.

Cooking: the control drives a high-voltage transformer, capacitor and diode that power the magnetron; a stirrer spreads the energy. Wolf rates cooking power at 950 W with ten power levels and sensor cooking.

Installation matters: Wolf says oversized mounting screws can bind the drawer so it will not close fully, and the unit must be level. Wolf also asks to check that the controls are not locked before calling a control fault.

Components & tests

Unlock all 6 components, specs, service mode and teardown

Full library + AI assistant + the OnCall Tech app for iPhone & Android. $34.90, one time.

Get lifetime access

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Large stainless refrigerator set flush between kitchen cabinets by Alex Qian, Pexels License

Diagnostic guides for this appliance

Guide · Microwave

Over-the-range microwave vent fan turns on by itself or won't turn off

Most OTR microwaves have a heat-protection thermostat that starts the vent fan when the cooktop below heats the unit, and on that cycle the fan cannot be switched off until the area cools. Some models also run the fan during and after microwave cooking or link the hood to the cooktop. If the fan runs in a cool kitchen, right at power-up, or for hours, suspect a thermostat stuck closed, a welded fan relay on the control board, a stuck vent key or a shorted wire.

8 steps ~45 minmoderate

Guide · Microwave

Microwave keypad locked or in demo mode (keys dead, or runs but doesn't heat)

Two software modes cause many no-fault calls: control/child lock and demo (showroom) mode, which runs everything except the magnetron. Clear them with the model's key sequence before any high-voltage diagnosis.

6 steps ~10 mineasy

Guide · Microwave

Known issue: Whirlpool WMH53520 / WMH73521 over-the-range microwave internal arcing (2016 recall)

In August 2016 Whirlpool recalled about 15,200 Whirlpool microwave hood combinations, models WMH53520 and WMH73521 (CS, CW, CB, CE, CH) with serial numbers TR33500000 to TR34899999, sold January 2014 to April 2016. Internal arcing during use can ignite an internal plastic part. The published remedy was a free replacement microwave. Units of this age are still installed in many homes and rentals.

6 steps ~20 mineasy

Other microwaves manuals

Manual · Microwave

LG LMV2031 / LMV1831 / LMVM2033 over-the-range microwave: quick sheet

LG 30-inch over-the-range microwaves LMV2031 (2.0 cu. ft., suffixes such as ST, SS, SB, SW, BD), LMV1831 (1.8 cu. ft., ST, SS, BD) and LMVM2033 (2.0 cu. ft., stainless). Transformer-type (non-inverter) units with a hidden vent grille, glass touch controls and a turntable, sold roughly 2015-2022; most are now listed as discontinued. LMHM2237 (2.2 cu. ft., taller cabinet, ExtendaVent 2.0) is a different, larger chassis: the fault logic below still applies, but check its own parts list before ordering anything.

10 components7 common failuresLG

Manual · Microwave

Frigidaire FFMV1846V / FFMV1645T / Gallery FGMV176NTF / FGMV17WNVF over-the-range microwave: quick sheet

Frigidaire 30-inch over-the-range microwaves: FFMV1846V (1.8 cu. ft., suffixes VS, VW, VB, VD), FFMV1645T (1.6 cu. ft., TS, TW, TB, TD, TM), Frigidaire Gallery FGMV176NTF (1.7 cu. ft.) and FGMV17WNVF (1.7 cu. ft.). Transformer-type units with a bottom grease filter, 2-speed vent and a turntable, sold roughly 2014-2021 and now discontinued (FMOS-series replacements). Factory revisions are shown by the last letter of the serial model (for example FFMV1846VSA/VSB); parts differ between revisions, so always order by the full model number.

10 components7 common failuresFrigidaire

Manual · Microwave

Galanz countertop microwaves (compact and retro, 0.7-1.2 cu ft): quick sheet

Galanz-branded countertop transformer microwaves sold at big-box retailers (e.g. GLCMKA07 retro 0.7 cu ft, 700 W; 1.1-1.2 cu ft models). Galanz also builds microwaves sold under other brand names; check the rating plate.

7 components5 common failuresGalanz