Weil-McLain UO-3 CV Check/Adjust ‘Z’ Dimension - ‘F’ heads, Burner Dimensions, Prepare the Burner

Prepare the Burner

Figure 4. Check/Adjust ‘Z’ Dimension for ‘F’ Heads

1-1/8”

1-3/8”

!WARNING

Adjust the ‘Z’ dimen- sion to the required specif cation.

Incorrect Adjustments could cause combus- tion problems, carbon deposition from flame impingement, heavy smoke generation and fire hazard.

yMake all adjustments exactly as outlined in the following information.

Check/Adjust ‘Z’ Dimension - ‘F’ heads

1.The important ‘Z’ dimension is the distance from the face of the nozzle to the flat face of the head (or heat shield, if applicable). This dis- tance for F heads is 1-⅛” (1-⅜” if the air tube has a heat shield). The “Z” dimension is factory set for burners shipped with the air tube in- stalled. Even if factory set, verify that the “Z” dimension has not been changed.

2.Use the following procedure to adjust the “Z” dimension, if it is not

correct:

yTurn off power to the burner.

yDisconnect the oil connector tube from the nozzle line

ySee above figure. Loosen the splined nut from the nozzle line. Loosen the hex head screw securing the escutcheon plate to the burner housing.

yPlace the end of a ruler at the face of the nozzle and, using a straight edge across the head, measure the distance to the face of the head. A Beckett T501 gauge may also be used.

ySlide the nozzle line forward or back until this dimension for F heads is 1-⅛” (1-⅜” to the face of the heat shield, if applicable).

yTighten the hex head screw to secure the escutcheon plate to the burner chassis. Then tighten the splined nut and attach the oil con- nector tube.

3.Recheck the “Z” dimension periodically when servicing to ensure the escutcheon plate has not been moved. You will need to reset the “Z” dimension if you replace the air tube or nozzle line assembly. The Beckett Z gauge (part number Z-2000) is available to permit checking the F head “Z” dimension without removing the burner from the appli- ance.

Burner Dimensions

	For usable length A (inches)
Dimension (inches)	F Head	L1	L2	V1
		Head	Head	Head
H (nozzle to head), +1/32	N/A	1/4	7/32	1/4
L (Total tube length)	A+1/2	A+1/2	A+1/2	A+1/2
R (electrode length), + 1/4	A+2-1/4	A+1-1/8	A+1-1/8	A+1-1/8
S (adapter to static plate), +	(Note 1)	1-3/8	1-3/8	1-3/8
1/16
Q (nozzle line length),	A+ 15/16	A+ 3/16	A+ 3/16	A+ 3/16
Z (F head-no heat shield)	1-1/8	N/A	N/A	N/A
(F head-with heat shield)	1-3/8	N/A	N/A	N/A
Z (L1 head w/straight	N/A	1-3/8	N/A	N/A
shroud) (L1/L2/V1 head	N/A	1-3/4	1-3/4	1-3/4
w/conic shroud)

Note 1: 1-3/8for dimension A less than 4”; 1-5/8 for dimension A from 4” through 4-1/2“, 2-13/32for dimension A greater than 4-1/2”.

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