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NORA Oilheat Technicians Manual

to be sure the flue pipe is connected with sheet metal screws and is supported. Step 12. Fire the unit and check operation: Start the burner, check the appearance of the flame and make sure that there is no impingement. Cycle the burner to check for prompt ignition, smooth operation and clean cut-off. Disconnect the thermostat leads and install a jumper across the T-T terminals to keep the burner running. Check the operation of the high limit control. Step 13. Efficiency test and adjustments: Perform a complete efficiency test and record the readings. The readings should be: • Smoke: zero to a trace • Draft: Unless the unit is designed for positive pressure, draft over-the-fire should be approximately -.02wc (negative point zero two inches) : 10½ to 12% • CO2 • Net stack temperature: over 350°F When you have finished adjusting the burner, remember to remove the jumper from the T-T terminals and replace the thermostat wiring. Step 14. The heating system: The following steps will vary depending on the type of heating system you are working on. If there is more than one thermostat, ask the customer to set each one 10 degrees above room temperature. Hot water system Check the zone valves and/or circulators to be sure each operates properly. If applicable, lubricate the circulator motor 14-8 Preventative Maintenance Tune-ups and bearing assembly. Check the circulator couplings and motor mounts. Check the control settings to be sure they’ll provide for proper heating, hot water, and circulator operation. Check the system pressure and the expansion tank. If there is an indirect water heater, check the circulator and control. Warm air system Open the blower compartment to clean, check and lubricate the blower if applicable. Check the air filters and clean or replace them. Note the filter size on your service ticket and remind the customer to check and clean/replace the filter regularly. Check the condition and tension of the fan belt, replace, and adjust as required. Check the blower mountings and bearings for excessive wear. Then properly reinstall the blower compartment door. Check the blower limit settings. If there is a humidifier, check it for proper operation, water leaks and mineral build up. Steam boiler Check the low water cutoff by draining water from the system until the burner shuts off. Check the automatic water feeder. Clean the sight glass and replace it and the washers if necessary. If the glass fills with dirty, oily water, skim the boiler until it clears up. Chapter 14 Preventative Maint./Tuneups


NORA Oilheat Technicians Manual
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