Bosch C 950 ES Installation Manual page 20

Installation instructions
3.3.7 Fan speed adjustment
! IMPORTANT INFORMATION:
Natural gas heaters with installation altitudes
below 2,000 ft above sea level disregard this
section.
Installation adjustment:
After installing the tankless water heater, the fan speed
values for minimum power (P2) and maximum power
(P1) may need adjustment due to variations in altitude
and vent pipe length. Failure to make necessary
adjustments to fan speed values may result in improper
operation of the appliance.
First calculate the total equivalent vent length. This is
the straight pipe length of both exhaust and combustion
air plus the number of elbows used. To determine the
length equivalency of each elbow refer to tables 5 and
6.
Use the equivalent vent length value to determine the
appropriate fan speed values found in table 18 and 19.
Refer to page 22 on how to adjust the fan speeds if an
adjustment is necessary. After changing fan speed val-
ues, proceed to section 6.5 to confirm CO2 values are
within specified ranges.
20
6 720 646 812