Installation Guide

Part number 550-100-066/0608
g a s -f i r e d w at e r b o i l e r — Boiler Manual
62
OFF — Function disabled.3.
Type 1 — This means the Ultra boiler is the primary heat 4.
source.
When the Ultra boiler receives a call for heat, it begins its a.
startup sequence and also starts a delay timer (set as ADD’L
HEAT DEMAND TIME).
When the delay timing is reached, the U-Control closes the the b.
“Additional heat demand contact,” terminals P16 #6 and #7.
Use this contact to start the next heat source.
If the next heat source is an Ultra boiler, connect this contact c.
to the boiler’s “heat demand 1” terminals (P11 #4 and #5).
Program the second boiler’s delay timer to start a third boiler
the same way, and so on to sequentially fire multiple boilers.
Type 2 — This means the boiler is the secondary heat source.5.
When the U-Control receives a call for heat, it immediately a.
activates the “Additional heat demand contact,” terminals P16
#6 and #7. This contact is used to start the next heat source
immediately.
When the delay timing is reached, the Ultra boiler begins its b.
startup sequence and continues to heat until the demand is
satisfied.
Type 2 assignment would generally only be used if the other c.
heat source is a different boiler or a heat pump, for example.
Type 3 — This assigns the boiler as the MASTER boiler in a mul-6.
tiple boiler system.
This MASTER boiler must have system supply and return a.
sensors mounted on the system supply and return pipes and
wired to the boiler.
When the U-Control receives a call for heat, it begins its heating b.
sequence and starts the additional heat demand delay timer.
When the delay timing is reached, the U-Control sends a 0–10 c.
VDC proportional signal out its 0–10 VDC output terminals,
P16 #1 and #2.
Connect these output terminals to the SLAVE boilers’ 0–10 d.
VDC input terminals, P15 #5 and #6. The slave boilers will
startup and modulate based on the signal strength. The slave
boilers must be set up as Type 4 (see below). They do not need
their additional heat timers to be setup.
An alternate method is to daisy chain the other boilers. That e.
is, connect the output of each to the input of the next. Each
of these boilers would be set up as a Type 4 (see below), and
each needs its additional heat timer set for the desired delay
between boilers.
Type 4 — This assigns the boiler as a SLAVE boiler in a multiple 7.
boiler system.
The boiler can be wired and setup to run in parallel with the a.
other SLAVE boilers as in 6c, above. Or they can be set up for
sequential operation following 6d, above.
When the boiler receives a 0–10 VDC input on terminals P15 b.
#5 and #6, it starts up and modulates firing rate according to
the signal.
If wired and setup per 6d above, it also starts its c.
additional heat delay timer immediately. When the
delay timing is reached, the U-Control sends out a
0–10 VDC signal (on terminals P16 #1 and #2) for
the next boiler.
The boiler uses the settings for Priority 1 while d.
receiving the 0–10 VDC signal.
ADVANCED SETUP – PRIORITY 1, 2, 3
Priority 1, 2 and 3 refer to the three possible heating 1.
inputs that can be handled by the U-Control.
Select the priority level desired for the application. 2.
Priority 1 is usually assigned to domestic water heating,
because of the need for quick response. Priority 2 and 3
usually used for space heating circuits.
Each of the three inputs has its own set of operating 3.
parameters, programmed using the menus shown in
Figure 85, page 64.
The inputs to the U-Control are:4.
Priority 1 — P11 #4 and #5, “heat demand 1”a.
Priority 2 — P15 #1 and #2, “heat demand 2”b.
Priority 3 — P15 #3 and #4, “heat demand 3”c.
ADVANCED SETUP – SYSTEM TYPE
For each priority being used, select the appropriate 1.
system type. See Figure 84 for system options and preset
temperatures.
The temperature presets are chosen based on normal 2.
best setting for these systems. The temperature values
can be changed, if desired, under “TEMPERATURES.”
ADVANCED SETUP – TEMPERATURES
Setup desired temperatures for each of the priorities 1.
used.
For an explanation of the target temperatures and as-2.
sociated outdoor temperatures, see Figure 83.
Outdoor temp for max target means the outdoor a.
temperature at which the target temperature reaches
its maximum value. In the example of Figure 83, this
occurs at 25 °F outside.
Outdoor temp for min target means the outdoor b.
temperature at which the target temperature reaches
its minimum. In the example of Figure 83, this oc-
curs at 70 °F.
Note that the reset lines are curved. The shape of this c.
curve is matched (or characterized) to the response
of the system type chosen to ensure the most effec-
tive reset operation.
U-Control operation and setup (continued)