Utica Boilers UB90-200 Installationsanweisungen

See “Troubleshooting” on page 31 for detailed sequences of 

operation and troubleshooting procedures. See separately 

provided “Repair Parts Manual” for locations of control 

components and accessories described.

• Integrated Boiler Control (IBC) is a microprocessor 

based controller for high efficiency gas boilers. 

• Controller monitors all safety controls which control 

operation of combustion air blower, circulator pump, 

burner, and combination hot surface igniter/flame 

sensor. 

• Controller is not intended for use with vent damper. 

Controller is mounted on control panel inside boiler. 

Contains five diagnostic indicator lights.

Gas Control Valve
Electronic 24 volt gas control valve contains 1:1 gas/air 

pressure regulator, controls gas flow to main burner of 

appliance. Suited for both natural and LP gas, and rated in 

accordance with ANSI Z21.21 - latest revision and CGA-

6.5-M95. 

• 120 volt hot surface igniter heats up 1800°F initiates 

combustion of gas in burner.

• Igniter is mounted next to burner through gas/air mixer. 
• Igniter also serves as means for proving main burner 

flame by flame rectification. 

A.  In event of lack of flame signal on three consecutive 

trials for ignition, IBC will lock out. 

B.  “Valve” and “Flame” diagnostic indicator lamps blink 

indicating failure mode as lack of flame signal. 

C.  Manually reset IBC from lockout by removing and 

re-establishing thermostat’s call for heat, or turn 

service switch off, then back on.  See Figure 19.

Maximum set-point of limit control must not exceed  

190°F.

• High limit control determines maximum boiler water 

temperature and provides means for protecting boiler 

and heating system from unsafe operating conditions 

which could damage boiler. 

• Control is mounted in ½” NPT control well and ¾” x ½” 

bushing on top of front boiler section at hot water outlet. 

• Control is tied in with IBC and factory set at 190°F water 

temperature. 

• High limit set-point is field adjustable and may be set 

between 100°F and 190°F. 

• Field set-point adjustment for each installation depends 

on heating system requirements. 

• Differentials are automatic, vary based on control 

settings and boiler temperature.

• Refer to limit manufacturer instructions provided with 

limit control.

Never run cold water into hot, empty boiler.

Casting temperature safety switch (230°F set-point) shuts 

off boiler by shutting off power to IBC, result of lack or loss 

of boiler water. Power indicator light goes out. 
Switch is installed on top of aluminum boiler section behind 

supply piping.
Fault requires manual reset of casting temperature safety 

switch, restarting boiler. Verify boiler is filled with water 

before resetting switch.