Service
WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.
Improper servicing could result in dangerous opera- tion, serious injury, death, or property damage. Before servicing, disconnect all electrical power to furnace.
When servicing controls, label all wires prior to dis- connecting. Take care to reconnect wires correctly. Verify proper operation after servicing.
At the beginning of each heating season, a licensed profes- sional technician (or equivalent) should check the system as follows:
Blower
Check the blower wheel for debris and clean if necessary. The blower motors are prelubricated for extended bearing life. No further lubrication is needed.
WARNING
The blower access panel must be securely in place when the blower and burners are operating. Gas fumes, which could contain carbon monoxide, can be drawn into living space resulting in personal inju- ry or death.
Filters
All EL280DF filters are installed external to the unit. Filters should be inspected monthly. Clean or replace the filters when necessary to ensure that the furnace operates prop- erly. Replacement filters must be rated for high velocity air- flow. Table 3 lists recommended filter sizes.
Flue And Chimney
1 − Check flue pipe, chimney and all connections for tight- ness and to make sure there is no blockage.
2 − Check unit for proper draft.
Electrical
1 − Check all wiring for loose connections.
2 − Check for the correct voltage at the furnace (furnace operating). Correct voltage is 120VAC + 10%.
3 − Check amp−draw on the blower motor with blower ac- cess panel in place.
Unit Nameplate__________Actual__________
Cleaning the Burners
NOTE − Use papers or protective covering in front of the fur- nace during cleaning.
1 − Turn off both electrical and gas power supplies to fur- nace.
3 − Label the wires from gas valve, rollout switches, prima- ry limit switch and make−up box then disconnect them.
4 − Disconnect gas supply piping. Remove the four screws securing the burner manifold assembly to the vestibule panel and remove the assembly from the unit.
5 − Remove 4 screws securing burner box and remove burner box.
6− To clean burners, run a vacuum cleaner with a soft brush attachment over the face of burners. Visually inspect in- side the burners and crossovers for any blockage caused by foreign matter. Remove any blockage. Figure 24 shows burner detail.
7− Reinstall burner box, manifold assembly and burner box cover.
8− Reconnect all wires.
9− Reconnect gas supply piping.
10− Turn on power and gas supply to unit.
11− Set thermostat and check for proper operation.
12− Check all piping connections, factory and field, for gas leaks. Use a leak detecting solution or other preferred means.
CAUTION
Some soaps used for leak detection are corrosive to certain metals. Carefully rinse piping thoroughly af- ter leak test has been completed. Do not use matches, candles, flame or other sources of ignition to check for gas leaks.
13− If a leak is detected, shut gas and electricity off and repair leak.
14− Repeat steps 12 and 13 until no leaks are detected. 15− Replace access panel.
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