Weil-McLain Ultra Commercial Installation And Start-Up Manual page 87

COMMERCIAL GAS
Troubleshooting
Troubleshooting suggestions for Ultra boilers
Condition
Display
Nothing Control is not receiving 120V
is shown power
in display
screen and no
other boiler
components
are operating
Nothing is Occurs when the
shown on communication is lost from
display screen, the U-control to the display.
but boiler is
operating
TEMP RISE TOO Occurs when supply
QUICKLY water temperature in heat
exchanger rises faster than
2ºF per second during the
first two minutes the burner
is on.
SUPPLY 58F > Boiler Out temperature
RETURN has exceeded the Boiler In
temperature by more than
58ºF
RETURN > Occurs when a return water
SUPPLY temperature is greater than
the corresponding supply
temperature by 10ºF or more.
Applies to system sensors or
boiler sensors.
Condition must occur for 10
minutes for system sensors.
Part number 550-100-086/0809
-
FIRED WATER BOILER
(continued)
(continued)
Diagnostics
Check service switch and/or
circuit breaker to boiler turned
is on.
Is there 120 Volts at the service
switch?
Is the Ultra's ON/OFF POWER
SWITCH located behind the
control pod turned on?
Check for 120 volts at the line
voltage terminal block located
inside the control pod.
Inspect 12-amp fuse as shown
on page 100. Replace if
necessary.
Check for loose connections
and proper pin alignment/
engagement on the U-Control's
plug P9 and the back of the
display circuit board.
Cycle power off and on using
boiler power switch and check
for operation.
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 after 30
second delay or using manual
reset on display.
After 20 automatic resets occur
the boiler will need a manual
reset.
Automatically resets when
condition no longer exists.
— Boiler Manual
Corrective Action(s)
Turn on service switch to power boiler.
Troubleshoot and correct the power supply to the service switch.
Turn the Ultra's power switch behind the control pod to ON.
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
U-control. See repair parts section for proper replacement part.
Replace with new display module. See repair parts section for proper
replacement part.
Verify water piping is installed correctly using primary/secondary
connection to the boiler loop.
Minimum pipe size for boiler loop is 2" unless boiler circulator selection
requires larger piping.
Verify proper circulator sizing for boiler size and system requirements.
See message displayed TEMPERATURE SENSOR and follow procedure for
loose connections.
Verify water piping is installed correctly using primary/secondary
connection to the boiler loop.
Minimum pipe size for boiler loop is 2" unless boiler circulator selection
requires larger piping.
Verify proper circulator sizing for boiler size and system requirements.
See message displayed TEMPERATURE SENSOR and follow procedure for
loose connections.
Verify proper flow direction of the boiler circulator. This circulator should
be installed to push water through the boiler's return pipe as shown in
Figure 7, page 15.
Verify proper placement of system sensors for single or multiple boiler
systems. System sensors should be on system piping not on the boiler
loop.
System sensors may need located further away from boiler loop
connection to the system if proximity to the boiler loop is causing
sensors to be heated inaccurately.
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