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Page 30 | Bradford White |
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6.4.2 High Altitude Adjustment and Set Up
Copper Brute II appliances may be operated at high altitude (7700 ft., 2347 m) with a reduction in output of approximately 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
No orifice changes are required to adjust the Copper Brute II 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 adjustments are a CO2 or O2 Analyzer and a
Start the adjustment process by checking the CO2 in the “as installed” condition. Adjust the air shutter(s) so that the CO2 is about 8% or the O2 is about 6.8% for appliances operating on Natural Gas. For appliances operating on LP Gas adjust the air shutter(s) so that the CO2 is about 9.2% or the O2 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 CO2 or O2 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 CO2 or O2 must be reset. CO2 or O2 will have changed when the manifold pressure was adjusted. Open the air shutter(s) to reduce the CO2 or O2 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 CO2 is adjusted to 8.0% for Natural Gas appliances or 9.2% for LP appliances. When using an O2 analyzer, the correct O2 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.
6.5 Shutting Down the Copper Brute II
1.Switch off the main electrical disconnect switch.
2.Close all manual gas valves.
3.If freezing is anticipated, drain the heater and be sure to also protect building piping from freezing.
This step to be performed by a qualified service person.
6.6To Restart the Copper Brute II
If drained, follow Section 6.1 in this manual for
proper filling and purging.
1.Switch off the main electrical disconnect switch.
2.Close all manual gas valves.
3.WAIT FIVE (5) MINUTES.
4.Set the aquastat or thermostat to its lowest setting.
5.Open all manual gas valves.
6.Reset all safety switches (pressure switch, manual reset high limit, etc.).
7.Set the temperature controller to the desired temperature setting and switch on electrical power.
8.Burner will go through a prepurge period and ignitor
SECTION 7.
Maintenance
7.1 System Maintenance
1.Lubricate the system
2.If a strainer is employed in a pressure reducing valve or the piping, clean it every six months.
3.Inspect the venting system for obstruction or leakage at least once a year. Periodically clean the screens in the vent terminal and combustion air terminal (when used).
4.Keep the appliance area clear and free from combustible materials, gasoline, and other flammable vapors and liquids.
5.If the appliance is not going to be used for extended periods in locations where freezing normally occurs, it should be isolated from the system and completely drained of all water. All systems connected to it should also be drained or protected from freezing.