The PRG304WH is Thermador’s 30-inch all-gas Pro Harmony® range: four open Pedestal Star® burners over a single 4.4 cu ft oven, built to the brand’s standard 24-inch cabinet depth rather than the deeper Pro Grand® commercial-depth cabinets. With 87,000 total BTU across the cooktop and no dual-fuel electric oven side to complicate diagnosis, most service calls land on one of two systems: a specific burner’s ignition or flame, or the single gas oven’s bake and broil performance.
Every burner and the oven igniter run off the same gas supply, so a no-light condition on more than one burner at once is worth checking against the supply line before assuming each igniter failed independently. If there’s any smell of gas or a burner that lights unevenly with popping or delayed ignition, shutting off the gas supply to the range comes first, before any other troubleshooting step. This is a 120V-only model with no Home Connect diagnostics, so troubleshooting relies on direct observation rather than an app or error-code display.
Key Features
- 30'' Pro Harmony® all-gas range, standard 24'' cabinet depth, 4 open Pedestal Star® burners
- 87,000 total BTU across the cooktop; ExtraLow® simmer setting on the burners
- 4.4 cu ft single oven cavity with 4 cooking modes: Roast, Bake, Convection Bake, Broil
- Porcelain and steel cooktop surface with cast-iron continuous grates; QuickClean Base®
- 120V/15A connection; this model is not Home Connect WiFi-enabled
Most Common Issues on This Model
A burner igniter clicking but not lighting, or not clicking at all
Oven igniter glowing but the gas failing to catch
Weak or uneven simmer on the ExtraLow setting
Bake or broil temperature running hot or cold against the dial setting
Grate or burner cap discoloration or warping affecting the flame pattern

