Installation Manual

ManualsBrandsBosch ManualsPlumbingTherm 18" Natural Gas Tankless Water Heater With 199,000 BTU Max Input, Energy Star Rated, Electronic Ignition, 150 PSI Max Water Pressure, Non-Condensing, In Grey

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Installation instructions

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Fig. 40 Space heating diagram

1 Hot water outlet

2 Cold water inlet

3 Pressure relief valve

4 Gas supply

5 Shut off gas valve

6 Thermal expansion tank (as required)

7 Atmospheric vacuum breaker

8 Cold inlet

9 Check valve

10 Pump

11 Thermostatic mixing valve

12 Thermometer (optional)

13 DHW outlet

14 Water to water heat exchanger

15 Backflow preventer

16 Automatic water feed

17 Thermostat

18 Space heating zone

19 Zone controller

20 Space heating pump

21 Expansion tank

22 Pressure relief valve

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