Carrier 58PHA/PHX instruction manual Igniter Position-Side View

58PHA

them thoroughly. A heavy build-up of soot and carbon indicates that a problem exists which needs to be corrected, such as improper adjustment of manifold pressure, insufficient or poor quality combustion air, incorrect size or damaged manifold orifice( s), improper gas, or a restricted heat exchanger. Action must be taken to correct the problem.

If it becomes necessary to clean the heat exchangers because of dust or corrosion, proceed as follows:

1.Turn OFF gas and electrical power to furnace.

2.Remove outer access door.

3.Disconnect vent connector from furnace vent elbow.

4.For downflow or horizontal furnace having an internal vent pipe, remove internal vent pipe within the casing.

5.Disconnect wires to the following components. Mark wires to aid in reconnection of (be careful when disconnecting wires from switches because damage may occur):

a.Draft safeguard switch.

b.Inducer motor.

c.Pressure switch(es).

d.Limit overtemperature switch.

e.Gas valve.

f.Hot surface igniter.

g.Flame-sensing electrode.

h.Flame rollout switches.

6.Remove screws that fasten the collector box assembly to the cell panel. Be careful not to damage the collector box. Inducer assembly and elbow need not be removed from collector box.

7.Disconnect gas line from gas manifold.

8.Remove the 5 screws that attach the burner assembly to the cell panel. The gas valve and individual burners need not be removed from support assembly. Remove NOx baffles if installed.

NOTE: Be very careful when removing burner assembly to avoid breaking igniter. See Fig. 56 and 57 for correct igniter location.

9.Using field-provided 25-caliber rifle cleaning brush, 36-in. (914 mm) long, 1/4” (6 mm) diameter steel spring cable, a variable speed, reversible electric drill, and vacuum cleaner, clean cells as follows:

a.Remove metal screw fitting from wire brush to allow insertion into cable.

b.Insert the twisted wire end of brush into end of spring cable, and crimp tight with crimping tool or crimp by striking with ball-peen hammer. TIGHTNESS IS VERY IMPORTANT.

9/32” 7.1mm

5/16”

7.9mm

A05025

Fig. 56 - Igniter Position-Side View

1-7/8

47.6 mm

A05026

Fig. 57 - Igniter Position-Top View

NOTE: The materials needed in item 9 can usually be purchased at local hardware stores.

(1.) Attach variable-speed, reversible drill to the end of spring cable (end opposite brush).

(2.) Insert brush end of cable into the outlet opening of cell and slowly rotate with drill. DO NOT force cable. Gradually insert cable into upper pass of cell. (See Fig. 58.)

(3.) Work cable in and out of cell 3 or 4 times to obtain sufficient cleaning. DO NOT pull cable with great force. Reverse drill and gradually work cable out.

(4.) Insert brush end of cable in burner inlet opening of cell, and proceed to clean 2 lower passes of cell in same manner as upper pass.

(5.) Repeat foregoing procedures until each cell in furnace has been cleaned.

(6.) Using vacuum cleaner, remove residue from each cell.

(7.) Using vacuum cleaner with soft brush attachment, clean burner assembly.

(8.) Clean flame sensor with fine steel wool.

(9.) Install NOx baffles (if removed).

(10.) Reinstall burner assembly. Center burners in cell openings.

10.Remove old sealant from cell panel and collector box flange.

11.Spray releasing agent on the heat exchanger cell panel where collector box assembly contacts cell panel.

NOTE: A releasing agent such as cooking spray or equivalent (must not contain corn or canola oil, aromatic or halogenated

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