Frymaster JCFX, MJCFEC, FMCFEC, J3F Thermostats And Temperature Probes, Functional Description cont

MASTER JET CF SERIES ATMOSPHERIC GAS FRYERS

CHAPTER 1: SERVICE PROCEDURES

1.1 Functional Description (cont.)

FREQUENTLY USED TEST POINTS FOR MODELS WITH INTERFACE BOARDS

		Meter
	Test	Setting	Pins	Results
12	VAC Power to Controller	50 VAC Scale	1 and 3 of J2	12-18
24	VAC Power	50 VAC Scale	24 VAC Terminals	22-28
24	VAC Power to Gas Valve	50 VAC Scale	6 on J1 and GROUND	22-28
120 VAC Power		250 VAC Scale	7 and 12 of J1	110-125
Probe Resistance*		R x 1000 OHMS	2 and 3 of J1	**

*Disconnect 15-Pin harness from controller before testing probe circuit.

**See Probe Resistance Chart at end of chapter.

Four LEDs, arranged across the top of the boards and identified in the table below, are provided to assist in troubleshooting.

MASTER JET SERIES INTERFACE BOARD

LED DIAGNOSTIC LIGHTS

GV	Indicates 24	VAC to the gas valve
AL	Indicates open Drain Safety Switch (if installed)
24V	Indicates 24	VAC from transformer
COMP	Indicates 12	VAC to computer

Every board contains one heat relay (K3), and may contain two basket lift relays (K1 and K2). As shipped from the factory, fryers with bell-crank basket lifts will have relays K1, K2, and K3. All other factory-original fryers will have boards with only relay K3.

NOTE: The basket lift option is not available on MJCF Series fryers. The above diagnostic tables are not applicable to user-supplied or KFC-1 computers.

THERMOSTATS AND TEMPERATURE PROBES

MJCF Series fryers equipped with thermostat controls have an adjustable controlling (operating) thermostat. The temperature at which the thermostat opens and closes is adjusted by changing the setting of the thermostat with an attached knob. When new, the Fenwal controlling thermostat is sensitive to one-degree changes in temperature.

CAUTION

Fenwal thermostats are used in a number of Frymaster products. The thermostat for the MJCF Series is 4 inches long. Do not use 3-inch Fenwal thermostats in MJCF Series fryers.

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