Bosch C 950 ES - Setting Fan Speed by Altitude and Piping

6 720 646 812
Installation instructions
21
Natural
Gas
Liquid
propane
Altitude
(above sea
level)
Vent
terminal
Total equivalent
vent length
1)
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 13
No
modification
required
No
modification
required
For operation at eleva-
tions above 2,000 ft
(610 m) the equip-
ment ratings shall be
reduced at the rate of
4% for each 1,000 ft
(305 m) above sea
level
26 - 46 ft 13
Twin
system
6 - 37 ft 13
38 - 62 ft 13
2000 - 4500 ft
(610 - 1372 m)
Concentric 6 - 25 ft 14* 47* 47*
26 - 46 ft 14* 48* 48*
Twin
system
6 - 37 ft 13* 47* 47*
38 - 62 ft 14* 48* 48*
4500 - 8000 ft
(1372 - 2439 m)
Concentric 6 - 25 ft 14* 48* 48*
26 - 46 ft 16* 48* 48*
Twin
system
6 - 37 ft 14* 48* 48*
38 - 62 ft 15* 48* 48*
* Above 2000 ft, CO2 levels must be checked with a combustion gas analyzer, see section 6.5 for instructions.
Table 18 Fan speed adjustment for 3" piping
1) Full equivalent length (inlet + outlet piping + fittings)
Natural
Gas
Liquid
propane
Altitude
(above sea
level)
Vent
terminal
Total equivalent
vent length
1)
Minimum power
fan speed (P2)
Maximum
power fan
speed (P1)
Maximum
power fan
speed (P1)
0 - 2000 ft
(0 - 610 m)
Concentric
3.5 - 39 ft 13
No
modification
required
No
modification
required
For operation at eleva-
tions above 2,000 ft
(610 m) the equip-
ment ratings shall be
reduced at the rate of
4% for each 1,000 ft
(305 m) above sea
level
40 - 86 ft 13
Twin
system
3.5 - 59 ft 13
60 - 126 ft 13
2000 - 4500 ft
(610 - 1372 m)
Concentric
3.5 - 39 ft 14* 47* 47*
40 - 86 ft 14* 48* 48*
Twin
system
3.5 - 59 ft 13* 47* 47*
60 - 126 ft 14* 48* 48*
4500 - 8000 ft
(1372 - 2439 m)
Concentric
3.5 - 39 ft 14* 48* 48*
40 - 86 ft 16* 48* 48*
Twin
system
3.5 - 59 ft 14* 48* 48*
60 - 126 ft 15* 48* 48*
* Above 2000 ft, CO2 levels must be checked with a combustion gas analyzer, see section 6.5 for instructions.
Table 19 Fan speed adjustment for 4" piping
1) Full equivalent length (inlet + outlet piping + fittings)