High Altitude Operation - Slant/Fin VGH-299-CH Installation And Service Manual

Model boiler
Natural gas
CO flue gas 3
2
Low fire – High fire
Propane
Natural gas
O flue gas 3
2
Low fire – High fire
Propane
Flue gas temperature at
combustion air temperature =
70 °F (20 °C)
Available pressure for the flue
system
4
INSTALLATION
T = 20 F
Resistance
boiler
T = 35 F
Pressure boiler min-max.
Max. supply temperature
ELECTRIC
Maximum power consumption
Power supply
Protection class
NOTES
CO or O of the unit measured/set without the boiler front panel in place
3
2 2
4 Maximum allowed combined resistance of flue gas and air supply piping at high fire
Table 3. 2

High altitude operation.

High Altitude Operation
The boiler is designed to operate at its maximum listed capacity in installations at elevations less than or equal to 2000 ft
(610 m) above Sea Level. Since the density of air decreases as elevation increases, maximum specified capacity will be
de-rated for elevations above 2000 ft (610 m) in accordance with the table underneath.
Elevations 2000 ft (610 m
In USA No de-rate
In Canada No de-rate
In USA and Canada, de-rate by 4% extra for every 1000 ft. above 4500 ft.
Combustion – At elevations above
a calibrated (altitude corrected) combustion analyzer to ensure safe and reliable operation. No orifices or
high-altitude kits are needed, since the 1:1 Gas/Air ratio of the gas valve and the venturi will respond
automatically to reduced air pressure.
NOTICE
It is the Installers responsibility to check the combustion of the appliance. Failure to follow these
instructions may result in property damage, serious injury, or death.
Table 3. 3
How to calculate De-rating at intermediate elevations for US:
Elevation between:
2000 and 3000 ft : (New value – 2000) x 0.004
3000 till 4000 ft : ((New value – 3000) x 0.004)+4
4000 till 4500 ft : ((New value – 4000) x 0.004)+8
Above 4500 ft : ((New value – 4500) x 0.004)+10 Example: Elevation is 4800 ft. De-rating is ((4800-4500)x0.004)+10 = 11.2 %
How to calculate De-rating at intermediate elevations for Canada:
Elevation between:
2000 till 4500 ft : All values derate by 10%
Above 4500 ft : ((New value – 4500) x 0.004)+10
VGH 299 CH
%
%
%
%
°F (°C)
Inch W.C (Pa)
26 (7.9)
ft.head (m.W.C.)
9 (2.7)
ft.head (m.W.C.)
psi (bar)
°F (°C)
W 180
V/Hz
-
)
3000 ft (914 m) 4000 ft (1219 m)
De-rate by 4 % De-rate by 8 %
De-rate by 10% De-rate by 10 %
2000 ft (610 m)
Example: Elevation is 2600 ft. De-rating is (2600-2000)x0.004 = 2.4 %
Example: Elevation is 3700 ft. De-rating is ((3700-3000)x0.004)+4 = 6.8 %
Example: Elevation is 4200 ft. De-rating is ((4200-4000)x0.004)+8 = 8.8 %
Example: Elevation is 3600 ft.
Example: Elevation is 7600 ft.
E93.1601EN032.C VGH installation manual
VGH 399 CH
9.8 – 9.2
11.0 - 10.4
3.7 – 4.7
4.1 - 5.0
120 – 180 (50 – 80)
0.8
(200)
31 (9.4)
10 (3.0)
15.0 - 87.0 (1.0 - 6.0)
185 (85)
200
120 / 60
IPX4D
4500 ft (1372 m)
De-rate by 10 %
De-rate by 10 %
, the combustion of the appliance must be checked with
De-rating = 10 %
De-rating is ((7600-4500)x0.004)+10 = 22.4 %
VGH 500 CH
29 (8.8)
10 (3.0)
280
Above 4500 ft (1372 m)
De-rate 4% per 1000 ft.
De-rate 4% per 1000 ft.
11