Weil-McLain SlimFit 2 Series Manual page 97

SlimFit ® Series 2
Troubleshooting
Figure 92 Troubleshooting suggestions for SlimFit boilers
Control Fault Displays, Diagnostics and Suggested Corrective Actions
Display Condition
Control is not receiving 24V
Nothing shown
on display power.
screen and
boiler will not
respond to call
for heat
Nothing shown Control is not receiving 24V
power.
on display
screen and
boiler will not
respond to call
for heat
Nothing Control is not receiving 120V
power.
is shown
in display
screen and no
other boiler
components
are operating
Occurs if the communication
Nothing is
shown on is lost from the control to the
display.
display screen,
but boiler is
operating
Display contrast needs to be
adjusted.
Occurs if supply water
TEMP RISE
TOO QUICKLY temperature in heat exchanger
rises faster than 2º F per second
during the first two minutes the
burner is on.
DISPLAY Occurs if display communications
COMM out for 30 seconds.
Fault
Part number 550-100-561/0224
commercial condensing gas
(continued)
Diagnostics
Check wiring for short circuit or
incorrect wiring.
Check 3-amp low voltage fuse on
control shown on page 94.
Check transformer connection to the
control per wiring diagram. Check
for 24V output of transformer.
Check wiring for short circuit or
incorrect wiring.
Check 3-amp low voltage fuse on
control shown on page 94.
Check transformer connection to the
control per wiring diagram. Check
for 24V output of transformer.
Check service switch and/or circuit
breaker to boiler is turned on.
Is there 120 VAC at the service
switch?
Check for 120 VAC at the line
voltage terminal block located inside
the top left electrical compartment.
Inspect 12-amp fuse as shown on
page 94. Replace if necessary.
Check for loose connections and
proper pin alignment/engagement
on the control's plug P9, Pump/Com
board P6 + J1, and the back of the
display circuit board.
Cycle power off and on using
boiler power switch and check for
operation.
or
Look at the screen from other
angles.
Automatically resets after 1 minute
delay or using manual reset on
display.
Manual reset is necessary after 5
automatic resets have occurred
during the same Priority heat
demand. Reset using manual reset
screen on display.
Automatically resets when
communication is re-established.
- — Boiler Manual
fired water boiler
(continued)
Corrective Action(s)
Correct wiring per wiring diagram including connection of transformer to the
control.
Replace fuse with proper part found in replacement part section of this manual.
If fuse blows again recheck wiring per diagram.
Replace transformer if it is receiving 120VAC, but not outputting 24VAC.
Correct wiring per wiring diagram including connection of transformer to the
control.
Replace fuse with proper part found in replacement part section of this manual.
If fuse blows again recheck wiring per diagram.
Replace transformer if it is receiving 120VAC, but not outputting 24VAC.
Turn on service switch to power boiler.
Troubleshoot and correct the power supply to the service switch.
Correct wiring inside the control pod using the wiring diagram in this manual.
Replace the fuse with proper part found in the replacement part section of this
manual. If fuse blows again recheck wiring per diagram.
Check for continuity on the wire harness from the display to the control. See
repair parts section for proper replacement part.
Replace with new display module. See repair parts section for proper
replacement part.
Power cycle the boiler, wait about 45 seconds then Press and hold the Enter
button. While holding the Enter button, tap the up or down buttons to adjust the
contrast level. If this does not work replace display.
Verify water pipe is installed correctly per instructions in this manual.
Verify proper circulator and speed for boiler size and system requirements.
See message displayed TEMPERATURE SENSOR and follow procedure for
loose connections.
Check for a loose connection at the molex plug on the control and connection
on the back of the display.
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