Specifications

Part number 550-100-090/0809
g a s -f i r e d w a t e r b o i l e r — Boiler Manual
30
U-Control operation and setup (continued)
EXPRESS SETUP — using default settings
The U-Control is factory programmed to supply a DHW circuit 1.
(control priority 1) and finned tube baseboard space heating (control
priority 2).
Control priority 3 is also available, and preset to run all three circulators 2.
if desired, but requires settings to be configured.
Factory default settingsFigure 35
Priority Type Target temperature Circulators
enabled
1
DHW
Direct
190°F #1 Only
2
Finned
tube BB
180°F fixed (if no outdoor sensor) or
180°F at 0°F outside / 130°F at 70°F
outside
#2 and #3
3 Custom
180°F fixed (if no outdoor sensor) or
180°F at 0°F outside / 130°F at 70°F
outside
None
You can use the factory default settings for most systems supplying 3.
space heating with finned-tube baseboard with or without a DHW
tank, provided:
A DHW tank, if used, must be piped directly to the boiler, as in the a.
piping shown in Figure 5, page 12 or Figure 6, page 13.
If the DHW tank is a separate zone off of the system main, or if it is b.
piped as in Figure 48, page 48, you will need to enable additional cir-
culators for DHW operation. The U-Control is factory programmed
to operate only the DHW circulator during DHW heating.
The heat emitters in the system must be finned tube baseboard only. c.
Other heat emitters require changes in the U-Control setup. See
ADVANCED INSTALLATION section for information.
Wiring to use the factory default settings — see information in 4. Fig-
ure 32, page 27 for wiring instructions.
For detailed control information
and additional wiring
, see the AD-
VANCED INSTALLATION section
of this manual.
Low-temperature systems (ra-
diant slab, etc.) — DO NOT use
the Ultra boiler control as the only
means of water temperature regula-
tion for low-temperature systems if
higher-temperature systems are also
supplied.