Figure 71.34. Space heating system.

Figure 71.34. Space heating system.

Remove the motor (47) from the motor

Blower Motor Test. Reassemble the blower

clamp (51).

assembly to test the motors. Connect a 24 vdc power

supply to the assembly and operate the motor. Check

Casing Disassembly.

the motor speed with a stroboscope. Minimum speed

(1) Remove the spark plug assembly (6),

allowed is: 5,000 rpm, circulating motor; 6,500 rpm,

spark plug seal washer (7), and spark plug

combustion motor.

seal (8) from the burner.

Blower, Burner and Combustion Chamber

(2) Remove the four screws (79) attaching

Reassembly.

the heater mounting base assembly (80)

(1) To assemble the blower, burner, and

to the casing; remove the base assembly.

combustion chamber, insert the burner

(3) Remove the seals (81) from the

assembly (40, fig.

71.35) into the

combustion air ports, and the five screws

combustion chamber. Align the burner

(24) fastening the casing assembly (1).

brackets with the screw holes in the

Spread the casing apart at the joint and

combustion chamber sides and fasten in

remove the combustion air blower

place with two washers (31) and screws

assembly (63), burner (40), and

(32), being careful to hold the burner in

combustion chamber (26) as an

place against the throat of the combustion

assembly. Withdraw the wires through

chamber.

the grommets (23) and (9) in the casing

during the removal.

Contact Plate. Refer to paragraph 194g.

AGO 5667A