Operating Guide

6 720 647 005 (2014/04)TRONIC 3000C Pro
Information about the heater | 7
2.7 Function
How the water heater works:
• Water comes in through the cold water inlet.
• The flow switch senses how much water is passing through
the unit. If it detects more than the preset level, the unit’s
heating elements switch on. This is shown by the neon light
glowing.
• The water is heated instantly as it passes through the
copper heat exchanger tube.
The temperature of the water coming out of the unit depends
on:
• The voltage of the electrical supply,
• The temperature of the incoming water supply,
• The setting of the power selector,
• The flow rate,
• The power rating of the unit.
• Depending on the region of the country, the temperature of
the water supply can vary between 40 °F in winter to 70 °F
in summer, with an average of 50 °F.
Fig. 3
[A] Manual reset thermal cut out
The table below shows the rise in water temperature you can
expect from the unit:
Manual reset thermal cut-out
The unit has a thermal cut-out (Fig. 1 ) which is mounted on
the heat exchanger tube. This will switch off the heater
elements if the water temperature goes above 194 °F.
If the cut-out trips it will need to be reset manually inside the
unit. This cut-out will only operate in exceptional
circumstances (Fig. 3 ). Call your service person or Bosch
Water Heating if this happens frequently.
The heater is designed for cold water supply
only. Do not supply with pre-heated water.
Model Volts Amps
Element
Resistance
High
Setting
Low Setting Temperature Rise (deg F) at Flow Rate (GPM)
0,5
GPM
0,75
GPM
1,0
GPM
1,5
GPM
2,0
GPM
2,5
GPM
US9 240 40 2x12 9,5kW - NA 84F 64F 42F 32F NA
US9 240 20 1x12 - 4,75kW NA 42F 32F 21F 16F NA
US9 208 35 2x12 7,1kW - NA 64F 48F 32F 24F NA
US9 208 18 1x12 - 3,5kW NA 32F 24F 16F 12F NA
US6 277 22 2x25 6,0kW - 81F 55F 42F 27F NA NA
US6 277 11 1x25 - 3,0kW 41F 28F 21F 14F NA NA
US3 120-110 27 2x8 3,4-3,0kW - 41F 28F 20F NA NA NA
US7 240-220 30 2x16 7,2-6,1kW - NA 63F 48F 32F 24F NA
US7 240-220 15 1x16 - 3,6- 3,05kW NA 32F 24F 16F 12F NA
Table 4