Specifications

Part number 550-100-090/0809
105
g a s -f i r e d w a t e r b o i l e r — Boiler Manual
MAINTENANCE & SPECIFICATIONS
Troubleshooting (continued)
Display
Condition Diagnostics Corrective Action(s)
DISPLAY COMM
Occurs when display
communications out for 30
seconds
Automatically resets when
communication is re-
established.
Check for a loose connection at the molex plug on the control and
connection on the back of the display.
LIMIT OPEN
Occurs when manual or
automatic reset limit opens.
Automatic external limit will
reset 2.5 minutes after external
limit device closes.
Manual limit fault must be reset
by choosing Reset Lockout on
the display.
Is there an external safety device connected? If yes, trouble shoot the
external limit to determine and correct the cause that opened the limit.
Also check for loose wiring connections.
Remove the top front cover and inspect the ORANGE - 4 PIN connector
P13.
Ensure a jumper is installed between pins 1&2 if not using a manual reset
external limit.
Ensure a jumper is installed between pins 3&4 if not using a automatic
reset external limit.
HIGH TEMP
LIMIT
Boiler temperature sensor
reached High Temp Limit
setting (no higher than 200°F)
Reset using manual reset screen
on display
Verify all isolation valves are open and circulators are programmed into
the U-Control properly. Each Priority input can be congured to turn
on any combination of three circulator outputs. Refer to the U-Control
Setup section to configure these properly for the system.
Verify water pipe is installed correctly using primary/secondary
connection to the boiler loop. Refer to Figure 4 page 11 for example of
primary/secondary connection.
Minimum pipe sizes
Ultra 80/105 - minimum 1 inch
Ultra 155/230 - minimum 1.25 inch
Ultra 299/399 - minimum 1.5 inch
Verify proper circulator sizing for boiler size and system requirements
starting on page 9.
Boiler ship with proper size circulators:
Ultra 80/105 - Taco 007
Ultra 155/230/299 - Taco 0014
Ultra 399 - Taco 2400-20
See message displayed TEMPERATURE SENSOR and follow procedure for
loose connections.
FLAME FAULT
Occurs when flame is
detected when there should
be no flame
Reset using manual reset screen
on display
Burner may be operating too hot due to incorrect combustion. Inspect
flame and conduct combustion test.
Force boiler into hi-re. Check ue gases with combustion analyzer and
correct using the maintenance and startup procedure in this manual.
Verify FLAME SIGNAL value quickly goes to zero on the DIAGNOSTICS -
INPUTS screen when the gas valve closes.
Check for flame at burner via flame current with burner off. Turn boiler
off and watch flame through observation port. If flame continues after
shutdown replace gas valve and venturi.
Troubleshooting (continued)
Figure 112 Troubleshooting suggestions for Ultra boilers (continued)