Unpacking the heater
The heater is default-set by the manufacturer to operate with
Natural Gas, for use with Liquid Propane, follow the conversion
instructions in section 6.8.1. Before commissioning the unit
be certain you have the heater correctly set for your type of
Gas - Propane or Natural Gas. Identification labels are found
on the shipping box, and on the rating plate which is located on
the left side (when facing appliance front) of the cover.
 Serial number
 Type of gas (Natural gas by default)
3.3.1 The box includes
LP Conversion Kit
Pressure relief valve
Bracket and screws for wall hanging the heater
Installation manual (manual can be downloaded at
The Greentherm T9900 SE/i are not approved or designed
Manufactured (mobile) homes, boats or any mobile
installation. (Modular homes are acceptable for
Use above 8000 ft A.S.L. altitude.
Applications where inlet water temperature is higher
than 140 °F (60 °C) for Residential appliances.
In these applications a 3 way valve or thermostatic
mixing valve must be installed.
Use with commercial dishwasher pre rinse spray valves.
In preheated inlet water applications (i.e. solar preheat),
activation flow rate will vary depending upon the unit set point,
inlet water temperature and the demand flow rate thru the unit.
Please consult Bosch for further details to determine if this will
function in your application.
3.3.2 Remove front cover
▶ Loosen two Phillips head screws located on the bottom of
the front cover (fig. 3).
Loosen two Phillips head screws
Greentherm T9900 SE/i – 6 720 813 635 (2019/03)