Bosch Tronic 3000 T point-of-use mini-tank (ES2.5, ES4, ES8): quick sheet

Covers: Tronic 3000 T ES2.5 (2.7 gal actual), ES4 (4 gal), ES8 (7.1 gal) 120 V electric mini-tanks.

Cross-checkedBrands: Bosch3 components

Small glass-lined 120 V tank for a sink or two: one 1,440 W element, a thermostat, T&P valve. ES4 and ES2.5 plug in; ES8 is hard-wired. Typical calls: no hot water (tripped high-limit or GFCI), drips at the T&P, low temperature.

Safety first

Turn off the breaker and verify zero volts before touching elements, thermostats or terminals; 240 V tank and tankless units can be lethal.
Never energize an element without water around it (dry fire).
Do not remove or plug the T&P relief valve; its discharge line must run to a safe spot.

How it works

A single 1,440 W element heats the small tank to the dial setting.

A high-limit/ECO cuts power on overheating; a T&P valve protects the tank.

Components & tests

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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.

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