YFG255 SERIES GAS RETHERMALIZERS
CHAPTER 1: SERVICE PROCEDURES
1-19
1.7.1 General Troubleshooting (cont.)
PROBLEM
PROBABLE CAUSES
CORRECTIVE ACTION
Heating indicator is on,
but burners will not
light.
A.
Float switch stuck or defective.
A.
Press the ON/OFF switch off. Clean
float switch and make sure that the
float switch is not bent and that the
float moves freely up and down. Then
press the ON/OFF switch on. Replace
if defective.
B.
Gas valve is not turned on.
B.
Turn the gas valve knob to the
ON
position.
C.
Manual gas shut off valve closed.
C.
Verify that any in-line manual shut off
valve is open. Verify that gas main
cut off valve is open.
Heating indicator cycles
on and off normally,
but burners will not
light.
A.
Failed controller.
A.
If available, substitute a controller
known to be working for the suspect
controller. If the rethermalizer
functions correctly, order replacement
from FAS.
Display shows a low
temperature,
and the rethermalizer
appears to operate
normally.
A. Defective probe.
A. Check temperature probe against
standard Minco probe resistance chart
on page 1-20. If defective replace
temperature probe.
Unit won’t fill with
water.
A. Water solenoid defective.
A. Replace the defective solenoid valve.
B. Float switch stuck or defective.
B. Press the ON/OFF switch off. Clean
float switch and make sure that the
float switch is not bent and that the
float moves freely up and down. Then
press the ON/OFF switch on. Replace
if defective.
C. Water supply turned off.
C. Check water supply valve. Use
bypass switch to fill.
Fluctuating or erratic
lighting of burner
flame.
A.
Incoming gas supply pressures are not
within range [Natural- 6-14" W.C.
(1.49-3.49 kPa); Propane- 11-14"
W.C. (2.74-3.49 kPa)]
A.
Inspect gas supply to rethermalizer.
Repair and/or replace faulty
components (defective supply shut-off
valves, incorrect piping size, etc.)
B.
Air in gas supply lines (new
installation).
B.
Allow unit to cycle on and off for
approximately 30 minutes to force air
from gas manifold and lines.