11.Reinstall condensate trap and tubing if previously removed.

a.Reinstall condensate trap in hole in blower shelf.

b.Connect condensate trap drain tubes. See Fig. 8 or tubing diagram on main furnace door for proper tube location.

(1.) Connect 1 tube (blue or blue and white striped) from collector box.

(2.) Connect 1 tube (violet or unmarked) from inducer housing.

(3.) Connect 1 tube (relief port, green or pink) from collector box.

c.Connect field drain to condensate trap.

NOTE: Ensure tubes are not kinked or pinched, as this will affect operation.

12.Reinstall control box, transformer, and door switch assembly on blower shelf.

13.Reconnect wires.

Refer to furnace wiring diagram, and connect thermostat leads if previously disconnected. (See Fig. 16.)

NOTE: Refer to Table 1 for motor speed lead relocation if leads were not identified before disconnection.

Table 1ÐSpeed Selector

COLOR

SPEED

FACTORY

ATTACHED TO

 

 

Black

High

Cool

Yellow (When Present)

Medium High

Spare

Blue

Medium Low

Heat

Red

Low

Spare

White

Common

Com

 

 

 

Heating speed selection MUST be adjusted to provide proper temperature rise as specified on the rating plate. Failure to adjust the heating speed may shorten heat exchanger life.

14.Turn on electrical supply. Manually close blower access panel door switch. Use a piece of tape to hold switch closed. Check for proper rotation and speed changes between heating and cooling by jumpering R to G and R to Y on control center thermostat terminals. (See Fig. 13.)

Blower access panel door switch opens 115-v power to control center. No component operation can occur. Caution must be taken when manually closing this switch for service purposes. Failure to follow this warning could result in personal injury or death.

15.If furnace is operating properly, release blower access panel door switch, replace blower access panel, and replace main furnace door.

Step 3ÐCleaning Burners

The following items should be performed by a qualified service technician. If the burners develop an accumulation of light dirt or dust, they may be cleaned by using the following procedure:

1.Turn off gas and electrical supplies to furnace.

2.Remove main furnace door.

3.Remove burner box cover.

4.Using backup wrench, disconnect gas supply pipe from gas valve.

5. Remove wires from gas valve. Note location for reassembly.

Label all wires prior to disconnection when servicing con- trols. Wiring errors can cause improper and dangerous operation.

6.Remove burner box pressure tube from gas valve regulator fitting.

7.Remove screws that secure manifold to burner box. (See Fig. 5.)

MANIFOLD

MOUNTING

SCREW

MANIFOLD

GAS VALVE

REGULATOR

FITTING

GAS VALVE

A93295

Fig. 5ÐBurner Box Assembly

8.Remove manifold, orifices, and gas valve as 1 assembly.

9.Remove screws attaching burner assembly in burner box.

10.Remove burner assembly from burner box.

NOTE: All burners are attached to burner bracket and can be removed as 1 assembly.

11.Clean burners with soft brush and vacuum.

12.Reinstall manifold, orifice, and gas valve assembly in burner box. Ensure manifold seal grommet is installed properly and burners fit over orifices.

13.Reconnect wires to gas valve. Refer to furnace wiring diagram for proper wire location.

14.Reinstall burner box pressure tube to gas valve regulator fitting.

15.Reinstall gas supply pipe to gas valve using backup wrench on gas valve to prevent rotation and improper orientation.

NOTE: Use propane gas resistant pipe dope to prevent gas leaks. DO NOT use Teflon tape.

Gas valve switch or knob MUST be facing forward or tilted upward. Failure to follow this warning could result in property damage, personal injury, or death.

16.Replace burner box cover.

17.Turn on gas and electrical supplies to furnace.

18.Check for gas leaks.

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Carrier 58MCA instruction manual ÐSpeed Selector, ÐCleaning Burners