The KBUIT4255E is a 42-inch built-in side-by-side refrigerator from Thermador’s older, pre-Freedom-Collection lineup, confirmed via Thermador’s own installation documentation to be part of the same electronically-controlled generation as the 48-inch KBUDT4865E. Unlike the current column-based Freedom Collection – where a household stacks separate refrigerator and freezer columns – this generation puts the fresh-food and freezer sections side by side behind two full-height doors in a single cabinet.
As with any legacy built-in this age, the ice maker (typically door-mounted on the freezer side in this configuration) and door seals are the most common wear items, often needing attention well before the sealed refrigeration system itself fails. The ‘E’ designation in Thermador’s older naming indicates the electronic-control generation, meaning a failed or erratic control panel is a distinct problem from the compressor and should be diagnosed separately – a unit that won’t respond to its control panel but is still audibly running its compressor points to the control board or panel, not necessarily the sealed system.
Key Features
- 42-inch built-in side-by-side refrigerator, panel-ready, electronic control generation
- Documented via Thermador's own installation instructions manual, which also covers the 48-inch KBUDT4865E variant
- Side-by-side vertical door configuration (fresh food and freezer side by side, not stacked)
- Shares its installation documentation with related KBUIT/KBUDT 42-inch and 48-inch models (4255E/4265E/4275E/4855E/4865E/4875E family)
Most Common Issues on This Model
Ice maker in the freezer-side door failing or jamming after years of use
Door seal wearing out on either the fresh-food or freezer side independently
Electronic control panel/display failing or showing erratic readings
Compressor short-cycling or running continuously without reaching temperature
Panel-ready door hinge sag under a long-installed custom panel