Bosch C 950 - Page 32

Installation instructions
C 950/C 1050 (Pro TL 175 C/199 C) – 6 720 805 440 (2019/10)
32
Table 27
4.3.8 Fan speed adjustment
NOTICE:
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 9 and 10.
Use the equivalent vent length value to determine the
appropriate fan speed values found in table 29 and 30. Refer to
page 36 on how to adjust the fan speeds if an adjustment is
necessary. After changing fan speed values, proceed to
chapter 7.5 to confirm CO
2
values are within specified ranges.
C 1050ES (Pro TL 199 C) Fan Speed Adjustment
Table 28 C 1050ES (Pro TL 199 C) Fan speed adjustment for 2" piping
Content Document
number
Part number
Side by side basic kit 6 720 804 523 7 736 501 100
Side by side extension kit 6 720 804 524 7 736 501 254
Back to back basic kit 6 720 804 520 7 736 501 253
Back to back extension kit 6 720 804 522 7 736 501 252
Natural Gas Liquid
propane
Natural Gas Liquid
propane
Altitude (above
sea level)
Vent
terminal
Total equivalent
vent length
1)
1) Full equivalent length (inlet + outlet piping + fittings)
Minimum
power fan
speed (P2)
Minimum
power fan
speed (P2)
Maximum
power fan
speed (P1)
Maximum
power fan
speed (P1)
0 - 2000 ft
(0 - 610 m)
Twin
system
3.5 - 11 ft 12
3)
17
3)
52
3)
52
3)
12 - 19 ft 12
3)
17
3)
52
3)
52
3)
2000 - 4500 ft
2)
(610 - 1372 m)
2) When installing in altitude, the unit may not reach the rated Input
Twin
system
3.5 - 11 ft 13
3)
17
3)
52
3)
52
3)
12 - 19 ft 13
3)
3) When adjusting the unit, CO2 levels must be checked with a combustion gas analyzer, see chapter 7.5 for instructions.
17
3)
52
3)
52
3)
Natural
Gas
Liquid
propane
Natural Gas Liquid
propane
Altitude (above
sea level)
Vent
terminal
Total equivalent
vent length
1)
Minimum
power fan
speed (P2)
Minimum
power fan
speed (P2)
Maximum
power fan
speed (P1)
Maximum
power fan
speed (P1)
0 - 2000 ft
(0 - 610 m)
Concentric 6 - 25 ft No modification required on installations below 2000 ft Altitude
26 - 46 ft
Twin
system
6 - 37 ft
38 - 62 ft