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VII: OPERATING
A.
WATER BOILERS SEQUENCE OF OPERATION
1.
Water Boilers with Tankless Heaters
(Warm
Start), Sequence Of Operation:
a. The V1 RO/FO Boiler is equipped with a Warm
Start Intelligent Oil Boiler Control (Warm Start
Boiler Control). The Warm Start Boiler Control
replaces the traditional high and low limit
aquastat and circulator relays.
b. The boiler’s sequence of operation is shown as
Status Codes on Boiler Control display. See
Table 5 and Figure 22.
c. When the thermostat calls for heat the boiler
control starts the system circulator and the
start sequence continues by energizing the oil
primary to operate the following sequence:
blower is started and operates for pre-purge
time; spark is energized and fuel valve is
opened for ignition trial time; burner fires until
the thermostat is satisfied. Optionally, the
thermal purge (circulator pre-purge time) maybe
added adjusting the Circulator Pre-purge time
parameter. This feature saves energy by starting
the circulator and delaying the burner start when
there is residual heat available in the boiler
Status Codes Displayed in
Mode
Status
Description
Standby
(burner off,
pump off)
No call for heat detected
Standby
(burner off,
pump on)
Either condition is true:
a. Call for heat detected and boiler
temperature higher than operating
setpoint.
b. Call for heat detected and boiler
temperature higher than 140 F and
Pump Pre-Purge Time has not
expired.
Running
The burner runs until the call for heat is
satisfied.
Self Test
Control internal checking
Table 5: Sequence of Operation
Figure 22: Intelligent Oil Boiler Control
(Horizontal Mount Shown)
d. If the thermostat is not satisfied and the
Operating Setpoint (SP) is reached the system
circulator will continue to operate and the burner
will stop. When the boiler water temperature
drops below the setpoint less the differential
setting the burner will restart.
e. After the thermostat is satisfied the burner and
circulator are stopped.
f. The Warm Start Boiler Control also includes
a low limit control function. When the boiler
water temperature falls below the Low Limit
Setpoint less the Low Limit Differential the
“ZC” terminal and System Circulator outputs
are de-energized and the oil primary is energized
to start the burner. As temperature rises above
the Low Limit Setpoint the burner is stopped,
the “ZC” output is energized and the System
Circulator is enabled to run in response to a call
for heat.
g. On burner start, if the CAD cell does not see
flame within approximately 15 seconds, primary
control will shut down the burner and enter into
a lockout mode. A lockout is reset by pressing
the reset button located on the primary control.
If the flame is lost while the burner is firing, the
primary control shuts down the burner, enters a
60 second recycle delay, and repeats the ignition
sequence. If after three (3) trials for ignition,
flame is not detected, primary control will enter
into restricted mode. Restricted mode is reset by
holding down the reset button for 15 seconds.
2.
Using Boiler Control
The Boiler Control is located on front of boiler.
The Boiler Control display, along with Up
ñ
,
Down
ò
,
and
“
I
”
keys may be used to view boiler
operating status (Figure 23).
3.
Viewing the Operating Mode Options
In operating mode the user may view (but not
change) boiler operating status, settings and
troubleshooting information. To view Boiler
Control display information:
Figure 23: Boiler Control
Key Function & Orientation
