Lincoln Series 1200, Series 1000 service manual

Intermittent heating	As Follows	Both the main fan motor and burner blower motor
		are equipped with thermal protection and will cease
		to operate if overheating occurs. This can cause
		the units to cycle on and off intermittently. This may
		be caused by improper ventilation. Also most of the
		problems listed under "oven will not heat" can
Conveyor will not run		cause intermittent failure.
	Voltage Supply	Check incoming voltage supply at line 1 to neutral.
(S/N 100-4389)		There should be a voltage reading of 120 VAC. If
		not present, check breakers.
	3 Amp Fuse	This conveyor fuse is located on the front panel.
		Replace if defective.
	Fuse Holder Conveyor Switch	Check and/or Replace. Same procedure as for fan
		switch.
	D. C. Motor Control Board	Check for 120 VAC input to D. C. control board
		across L1 and L2. Check the 3 amp fuse on the D.
		C control board. Check for D.C. voltage at terminal
		F1 and F2. Voltage should be 100 VDC ± 10
		steady. If this voltage is not present, replace D. C.
		control board. Check for D. C. voltage output to the
		motor across terminals A1 and A2 (this voltage
		should be approx. 125 VDC at maximum conveyor
		motor speed).
	Speed Control Potentiometer	This is a 0 to 400 ohm or 0 to 500 ohm, 10-turn
		potentiometer. WITH POWER OFF: remove the
		red, white, and black leads from terminals S1, S2,
		S3. With a digital multimeter, check the ohm
		reading across the red to black leads. This ohm
		reading should be a steady 400-ohm, or 500-ohm,
		through the entire 10-turn rotation of the
		potentiometer. Red to white, should be 0-400 or 0-
		500 ohms as the pot. is rotated. Check for shorts or
		opens or unsteady, ohm reading, if potentiometer is
		defective, replace. If the potentiometer checks OK,
		and
		there is no output at terminals A1 and A2, replace
		the D.C. control board.
	Reversing Switch	If there is D. C. voltage output from the motor
		control board, but the conveyor drive motor is not
		running, check the D.P.D.T. reversing switch.
	Conveyor Drive Motor	Check the conveyor drive sprocket for tightness.
		Disconnect the motor, check the red and black
		motor leads for opens, shorts or grounds. Check
		the brushes for excessive or	abnormal wear.
		Replace as needed. Reconnect motor. Test for
Conveyor will not run		operation. If motor does not run, replace.
	Voltage Supply	Check incoming voltage supply at line 1 to neutral.
(S/N 4390 to Q14974		There should be a voltage reading of 120 VAC. If
1000 Series		not present, check breakers.
S/N 4390-Q14790	3 Amp Fuse	This conveyor fuse is located on the front panel.
1200 Series)		Replace if defective.
	Fuseholder	Check and/or Replace
	Fan Switch	See procedure for checking on page 26.
	Conveyor Switch	Same procedure as for fan switch.
NOTE:	(Dual Belt Ovens)	Dual belt ovens utilize 2 complete independent
		conveyor drive systems. The trouble shooting
		procedures are the same as single belt ovens,
		except that the dual belt ovens use one each of the
		following: one "A" DC. control board and one "B" D.
		C. control board.

Impinger I -–1000 Series Service Manual - International 33