Takagi default output temperature is 120°F. Residential cap is 140°F. Commercial override extends to 185°F with installer enablement.
Why 120°F default
- Scald safety: 120°F causes burn in 5-10 min; 140°F in 5 seconds
- Energy: every 10°F over 120°F adds 3-5% gas use
- Heat exchanger longevity: higher setpoints accelerate scale
How to set
- Use the wired remote controller (Takagi standard accessory)
- Up/down arrow buttons to adjust
- Range 100-140°F residential
- Commercial override (above 140°F): service menu, requires installer
When to deviate from 120°F
- Dishwasher needs 130-135°F: raise unit + install thermostatic mixing valve at fixtures
- Legionella concerns in homes with infrequently-used fixtures
- Recirculation loop temp loss: raise source to compensate
- Commercial sanitation: 180°F for high-temp dishwasher rinse
T-T commercial cascade temperature
The cascade controller sets a target output temperature; all units modulate to maintain it. Individual unit controllers are slave to the cascade controller.
Bottom line
120°F unless a specific use case forces higher. Use thermostatic mixing valves at fixtures for safety when raising heater temperature.