COPPER BRUTE II (500 - 2000) | Page 51 |
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SECTION 8.
Trouble Shooting
8.1Resolving 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
If it does not, check the gas supply pressure to the appliance, after resetting the appliance and attempting another
2.Poor Combustion: Poor combustion should be suspected if there is a strong flue gas odor. The odor may result from an improper gas/air ratio (high or low O2 or CO2). Copper Brute II appliances operate best with 45% excess air (8% CO2 on natural gas, 9.2% CO2 on LP). Check the CO2 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
8.2Delayed 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.
8.3Short Cycling — Boiler
Because the Copper Brute II is a
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
a load distribution problem. See Section 6.3 regarding controller setup. Contact your Bradford White representative to discuss possible remedies.
8.4Short 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
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 flow through the water heater. The cause should be determined and corrected.
8.5High Gas Consumption
Appliances operating with an improper air/
fuel ratio are very inefficient and consequently, have very high gas consumption. Because efficiency is high when the CO2 is high (or O2 is low), appliances operating with low CO2or high O2 (especially LP appliances) consume more gas. Adjust the CO2 or O2 for optimum efficiency. If no combustion analyzing equipment (CO2 or O2) is available then a proper adjustment of the air/fuel ratio (CO2 or O2) cannot be accomplished. However, by briefly sniffing the flue gases it is possible to determine if the CO2 or O2 is within the proper range. No significant flue gas odor should be detected when combustion is proper. A strong piercing smell indicates poor combustion and generally a lean mixture - low CO2 or high O2 . The CO2 should be 8% at high fire. To check the CO2, first 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 firing, 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 CO2, and adjust the air shutters if further adjustment to the CO2 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 final adjustment is made.
