Bunn AFPO-3, AFPO-2 SL service manual MIX RATIO ADJUSTMENTScont

MIX RATIO ADJUSTMENTS(cont.)

6.Compare results with chart or formula below.

7.If the time observed is too short or long, turn the needle valve clockwise or counterclockwise, respectively, a little at a time. Repeat from the preceding step until correct.

Mix ratio (water/flavor)	Time for FLAVOR OUTPUT (1/2 cup)	Time for WATER OUTPUT (1 cup)
1+1	assume 20 sec. or obtain time per note below	40 sec. or 2 times flavor output time
2+1	assume 20 sec. or obtain time per note below	20 sec. or equal to flavor output time
3+1	assume 20 sec. or obtain time per note below	13.3 sec. or 0.67 times flavor output time
4+1(see below)	assume 20 sec. or obtain time per note below	10 sec. or 0.5 times flavor output time
5+1	assume 20 sec. or obtain time per note below	8 sec. or 0.4 times flavor output time
6+1	assume 20 sec. or obtain time per note below	6.7 sec. or 0.33 times flavor output time

NOTE: For a typical adjustment, the time for flavor output in the center column above is assumed to be 20 seconds. A more specific flavor pump output time may be obtained prior to adjustment of the needle valve. To do so, connect the flavor to be tested to the “FLAVOR INPUT”, and the test hose to the corresponding “FLAVOR OUTPUT” (make no connection to the “WATER INPUT”). With a one-cup container under the test hose press the corresponding “TEST OUTPUT” switch, and carefully measure and note the elapsed time from when the product first flows from the test hose to when one-half cup of the product has been dispensed. This value may then be used in the formula below. Following flavor pump output measurement, disconnect the flavor line from the “FLAVOR INPUT” and purge remaining product from the line.

Formula for setting mix ratio: To obtain the time for dispensing 1 cup of water, divide the time it takes to dispense one-half cup of product by the first number in the mix ratio and then multiply the result by two.

Example: W=2(F/X) Where W is the time it should take to dispense one cup of water, it took F seconds (20 here) to dispense 1/2 cup of flavor concentrate, we desire a mix ratio X of 4+1 (X will be the first number in the mix ratio, 4).

Therefore:	W = 2/(20/4)
	W = 2/5
	W = 10 seconds

So if it took 20 seconds to dispense one-half cup of flavor concentrate, and a mix ratio of 4 to 1 is required, the needle valve should be adjusted to dispense 1 cup of water in 10 seconds. NOTE: Hoses and tubing should be primed and free of substantial air spaces and/or bubbles prior to calibration.

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NEEDLE VALVE	P1521
5	28791 040501