Technical information

12/01/02

Note: The Thermistor must be mounted using a heat

sink compound to assure good heat transfer and ac-

curate sensing. Use Hoshizaki Part Number 4AO683-

01 or equivalent. (Radio Shack #276-1372 or GE Elec-

tronics #10-8108, ect.)

3. CONTROL BOARD: The electronic control board

maintains the sequence of operation. There are 3

input connections to the board.

1. The Float switch connects to the control board

through the black K5 connector.

2. The thermistor connects to the control board

through the white K3 connector.

3. If a mechanical bin control is used, it will connect

to the K4 Red connector. ( In this case, dip switch

#7 must be set to the ON position.)

The control transformer supplies 10.5 VAC control

voltage to the K2 connection. The control board will

not operate unless control voltage is present at K2.

Proper control voltage is indicated by the Power

OK red LED ON.

The final connector on the control board is the K1

10-pin connector. This connector supplies 115 VAC

into the control board switchin components or

relay contacts and powers the individual com-

ponents during the sequence of operation.

The control board also has 10 dip switches that

allow for board adjustments. These switches are

set from the factory for proper operation and maxi-

mum efficiency. See control board adjustment chart

for factory settings and adjustments.

BOARD CHECKOUT: Before replacing a control

board that does not show a visable defect and

that you suspect is bad, always conduct the fol-

low checkout procedure. This procedure will help

you verify your diagnosis.

1. Check the dip switch settings to assure that

#3,4, 7, 8, 9, & 10 are in the factory setting. Out-

put test switch S3 should also be OFF. Switches

1, 2, 4, & 5 are cleaning adjustments and the set-

tings are flexible.

12/20/03

2/20/03