Page 16
B
RADFORD
W
HITE
C
ORP.
6. With the unit running, verify the supply gas pressure, manifold gas pressure, and CO
2
according to the
table below.
Natural Gas
Propane
Supply Gas
Pressure
Typical
7” w.c. (1.7kPa)
11” w.c. (2.7kPa)
Range
5” w.c. ≤ (supply pressure ) ≤ 13” w.c.
Manifold Gas Pressure
2.5” w.c. (0.62 kPa)
CO
2
8%
9.2%
Table 4. Supply Gas Pressure
7. After placing the appliance in operation, the
Burner Safety Shutoff Device must be tested
.
To test:
(a) Close gas shutoff valve with burner operating.
(b) The flame will go out and blower will continue
to run for the post purge cycle. One additional
attempt to light will follow. Ignition will not occur
as the gas is off. The ignition control will lockout,
and will have to be reset before the unit will
operate.
(c) Open gas shutoff valve. Restart the appliance.
The ignition sequence will start again and the
burner will start. The appliance will return to its
previous mode of operation.
NOTE:
Sizes 1000–2000 have two ignition controls
and two ignitors, which work independently of one
another. If the ignition control for stages 1 and 2
fails to properly light the main burners for those
stages, the second ignition control will still be
active, and will be able to energize stages 3 and
4. This, of course, will only occur if all other safety
devices confirm that the unit will run in a safe
condition.
4.B
Set Up for High Altitude
( >2500 Feet )
Copper Brute ll appliances may be operated at
high altitude (7700 ft., 2347 m) with a reduction in
output of approx-imately 10%. At altitudes of less
than or more than 7700 ft. (2347 m) the appliance will
perform equally as well, but with differing reductions in
output. At elevations higher than 7700 ft. (2347 m) the
reduction in output will exceed 10% and at elevations
below 7700 ft. (2347 m) it will be less than 10%. High
altitude adjustment must not be made on appliances
operating at elevations below 2500 ft. (762 m).
No orifice changes are required to adjust the
Copper Brute ll appliances for high altitude. High
altitude adjustment is accomplished by adjustment of
the gas valve manifold pressure and the air shutter(s).
The required instruments used to assist in these
adjust-ments are a CO
2
or O
2
Analyzer and a U-Tube
Manometer or other device capable of reading a
pressure of 2.5-3.0 inches w.c. (0.62-0.75 kPa).
Start the adjustment process by checking the
CO
2
in the “as installed” condition. Adjust the air
shutter(s) so that the CO
2
is about 8% or the O
2
is
about 6.8% for appliances operating on Natural Gas.
For appliances operating on LP Gas adjust the air
shutter(s) so that the CO
2
is about 9.2% or the O
2
is
about 6.8%. Appliances with two blowers should be
adjusted so that the air shutters below each blower are
open the same amount.
Once the CO
2
or O
2
has been set, the manifold
pressure may be adjusted. Remove the 1/8 NPT plug
from the lower side of the gas valve that is to be
set and install a fitting, hose and manometer. Start
the appliance and observe the manifold pressure.
Manifold pressure must be adjusted to 3.0 in. w.c.
(0.75 kPa) (for high altitude only, standard operating
pressure is 2.5 in. w.c. (0.62 kPa)). It is adjusted by
removing the slotted cap on the gas valve and turning
the adjustment screw (beneath the cap) clockwise to
increase pressure and replaced after the adjustments
have been completed and the fitting, hose and
manometer have been removed and the 1/8" plug has
been replaced. Repeat this process until all gas valves
have been set.
Note:
The pressure can be set only
when the appliance is operating and only when the
particular gas valve being adjusted is energized by a
call for heat from the staging control.
After all of the gas valve manifold pressures have
been set, the CO
2
or O
2
must be reset. CO
2
or O
2
will have changed when the manifold pressure was
adjusted. Open the air shutter(s) to reduce the CO
2
or
O
2
to the values achieved previously.
The procedure is complete when all gas valves are
adjusted to a manifold pressure of 3.0 in. w.c. (0.75
kPa) and the CO
2
is adjusted to 8.0% for Natural Gas
appliances or 9.2% for LP appliances. When using an
O
2
analyzer, the correct O
2
is 6.8% for both Natural
Gas and LP appliances.
Caution
Should any odor of gas be detected, or if the
gas burner does not appear to be functioning
in a normal manner, close main shutoff valve,
do not shut off switch, and contact your heating
contractor, gas company, or factory representative.
H2380200-
Ambler, PA 19002
Tech. Service (800) 334-3393
Service Parts (800) 538-2020
www.BradfordWhite.com
Warranty Service (800) 531-2111
Litho in U.S.A. © Bradford White 1711 Document 1393
200 Lafayette St.
Middleville, MI 49333
Warranty: (800) 531-2111
