1-4
FREQUENTLY USED TEST POI NTS FOR INTERFACE BOARD 106-0 386SP
Meter
Setting
12VAC Power to Controller 50VAC Scale 1 and 3 on J3 or J2 12-18
24VAC Power to Right Module 50VAC Scale 8 on J3 and GROUND 22-28
120 VAC Power 250VAC Scale 11 on J3 and GROUND 110-125
120 VAC Power to Blowers 250VAC Scale 12 on J3 and GROUND 110-125
24VAC Power to Full- or Right -vat High-Limi t 50VAC Scale 9 on J3 and GROUND 22-28
24VAC Power to Left High-Limi t (if present ) 50VAC Scale 9 on J1 and GROUND 22-28
Probe Resistance (Ful l- or Right-vat ) * R x 1000 OHMS 2 and 6 on J3 or 13 and 14 on J 2 **
Probe Resistance (Lef t - if present ) * R x 1000 OH M S 2 and 6 on J1 or 14 and 15 on J2 **
Probe Isolati on R x 1000 OHMS 6 on J1 or J3 and GROUND ***
High-Limit Conti nuity (Full- or Right-vat) R x 1 OHM 9 on J3 and Wire 13C on Gas Valve 0
High-Limit Conti nuity (Left - if present) R x 1 OHM 9 on J1 and Wire 12C on Gas Valve 0
** See Probe Resistance Chart at end of chapter.
*** 5 mega-Ohms or greater.
Test Pins Results
** Disconnect 15-pin harness from controll er before testing pr obe circuit.
1.1.3 THERMOSTATS
BIPH52/55 and MPH52/55 Series gas fryers have temperature probes located on the front centerline
of each frypot (dual-vat frypots have two probes, one in each vat). In this type of thermostat, the
probe resistance varies directly with the temperature. That is, as the temperature rises, so does
resistance, at a rate of approximately 2 ohms for every 1º F. Circuitry in the controller monitors the
probe resistance and controls burner firing when the resistance exceeds or falls below programmed
temperatures (setpoints). The temperatures are programmed by means of a keypad on the face of the
controller.
BIPH52/55 and MPH52/55 Series fryers are also equipped with a high-limit thermostat. In the event
that the fryer fails to properly control the oil temperature, the high-limit thermostat prevents the fryer
from overheating to the flash point. The high-limit thermostat acts as a normally closed power
switch that opens when exposed to temperatures above 425ºF to 450ºF (218ºC to 232ºC). The
different types of thermostats have different part numbers for CE and Non-CE models, and are not
interchangeable.
1.2 Accessing Fryers for Servicing
DANGER
Moving a fryer filled with oil may cause spilling or splattering of the hot liquid.
Follow the draining instructions in Chapter 4 of the BIPH52/55-MPH52/55 Installation
and Operation manual (P/N 819-6087) before attempting to relocate a fryer for
servicing.
1. Shut off the gas supply to the unit. Unplug the power cords. Disconnect the unit from the gas
supply.