Frymaster Gas Rethermalizers FBRA18 Series - Manual (Page 39)

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6.7.3 Improper Temperature Control
Temperature control is a function of several interrelated components, each of which must operate
correctly. The principle component is the temperature probe. Other components include the inter-
face board, the water level sensors (on FBRA18 units), the controller, and the ignition module.
Whatever the cause, the symptom is failure of the unit to attain or maintain setpoint temperature.
On FBR18A models, the unit will not call for heat unless the controller senses that the unit is full of
water. Sensing is accomplished when the water level in the cookpot contacts the upper water level
sensor, grounding it. If the mineral content of the water is unusually low, such as with distilled, pu-
rified, or highly filtered water, the water will not ground the sensor. If this is the cause, adding ap-
proximately ⅛-cup of salt to the water will usually solve the problem.
Similarly, if the upper water level sensor becomes encrusted with lime, starch, or some other build-
up, it will not ground properly. The solution is to clean the water level sensors thoroughly with a
Scotchbrite™ or similar nylon scouring pad. NOTE: Do not use deliming solution to clean these
units. Use of deliming solution will damage all stainless steel parts.
CAUTION
Do not use deliming solution to clean these units. Use of deliming solution will dam-
age all stainless steel parts.
6.8 Troubleshooting Guides
The troubleshooting guides found in the pages that follow are intended to assist service technicians
in quickly isolating the probable causes of equipment malfunctions by following a logical, step-by-
step process. An additional set of operator troubleshooting guides is contained in Chapter 5. It is
suggested that service technicians thoroughly familiarize themselves with both sets.