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COPPER BRUTE II (500 - 2000)
a load distribution problem. See Section 6.3 regarding
controller setup. Contact your Bradford White
representative to discuss possible remedies.
8.4 Short Cycling — Water Heater
Short cycling will generally occur only in
combination space heating and water heating
applications when the water heater is operating in the
space-heating mode. Because the Copper Brute II is a
stage-red water heater and its input will reduce when
there is a reduction in heating load, short cycling is
greatly reduced. If the heating load drops below the
minimum input of the water heater for an extended
period, the water heater will have a tendency to short
cycle. If short cycling is frequently experienced,
regardless of the control’s attempt to limit it, the
heating load should be redistributed to control it. See
Section 6.3 regarding controller setup.
If short cycling occurs in a water heater
application, it is probably caused by undersized
piping between the water heater and the storage tank
or by some other factor that restricts proper water
ow through the water heater. The cause should be
determined and corrected.
8.5 High Gas Consumption
Appliances operating with an improper air/
fuel ratio are very inefcient and consequently, have
very high gas consumption. Because efciency is
high when the CO
2
is high (or O
2
is low), appliances
operating with low CO
2
or high O
2
(especially LP
appliances) consume more gas. Adjust the CO
2
or O
2
for optimum efciency. If no combustion analyzing
equipment (CO
2
or O
2
) is available then a proper
adjustment of the air/fuel ratio (CO
2
or O
2
) cannot be
accomplished. However, by briey snifng the ue
gases it is possible to determine if the CO
2
or O
2
is
within the proper range. No signicant ue gas odor
should be detected when combustion is proper. A
strong piercing smell indicates poor combustion and
generally a lean mixture - low CO
2
or high O
2
. The
CO
2
should be 8% at high re. To check the CO
2
, rst
verify that the supply gas pressure is within 5" to 13"
w.c. (1.2 to 3.2 kPa) With the Copper Brute II running
with all stages ring, set the air box pressure to 1.5"
w.c. (0.37 kPa) (as a starting point), by adjusting the
air shutter(s) at the bottom of the fan(s). Check the
CO
2
, and adjust the air shutters if further adjustment
to the CO
2
is needed. Sizes 1250 to 2000 have two
blowers and two air chambers (boxes). The pressure of
each air box must be equal when the nal adjustment
is made.
SECTION 8.
Trouble Shooting
8.1 Resolving Lockouts
There are many causes of lockouts. The three
most common causes are: (1) inadequate gas supply,
(2) poor combustion, (3) ignitor failure.
1. Inadequate gas supply: Before proceeding, ensure
that the gas supply has not been shutoff or the LP
tank (LP boilers) is not empty. Then, restart the
boiler and observe the operational cycle. After
a 15-second fan pre-purge, the ignitor will heat
up for 20 seconds, and then the unit will light.
If it does not, check the gas supply pressure to
the appliance, after resetting the appliance and
attempting another start-up. The gas pressure
to the appliance must be above 5" w.c. (1.2kPa)
throughout the entire start-up cycle. If it is not,
correct the supply problem (check gas valves or
supply piping). If the supply pressure is adequate,
consult the factory for assistance.
2. Poor Combustion: Poor combustion should
be suspected if there is a strong ue gas odor.
The odor may result from an improper gas/air
ratio (high or low O
2
or CO
2
). Copper Brute II
appliances operate best with 45% excess air (8%
CO
2
on natural gas, 9.2% CO
2
on LP). Check the
CO
2
of the appliance and adjust if necessary.
3. Ignitor failure: If the boiler goes through a
normal start cycle but combustion does not
occur, ignitor failure should be suspected. Check
the ignitor by unplugging the ignitor plug and
measuring the ignitor resistance. It should be
50-80 ohms. If the resistance is not 50-80 ohms,
replace the ignitor. If the resistance is correct,
reset the boiler and check for 120 VAC at the
ignitor plug during the start cycle. If there is no
voltage, replace the faulty ignitor wire harness or
the ignition control.
8.2 Delayed Ignition — Possible Causes
A defective burner can cause a delayed ignition.
If the gas supply pressure is proper and the gas
valves are functioning properly, then burners should
be inspected. There should be no distortion or
perforations in the burners outside of the active burner
port area. Replace if indicated.
8.3 Short Cycling — Boiler
Because the Copper Brute II is a stage-red
boiler, and its input will decrease when there is a
reduction in heating load, short cycling is greatly
reduced. If the heating load drops below the minimum
input of the boiler for an extended period, the boiler
will have a tendency to short cycle. This can be a
symptom of improper control strategy or setpoints, or