100
XII. Operation
(continued)
the operating setpoint reverts to the value determined
by the Outdoor Air Reset settings. If Boost Time is
zero, then the boost function is not used.
7. Domestic Hot Water (DHW) Setpoint
Upon a DHW call for heat the setpoint is the user entered
DHW setpoint . The optimal value of this setpoint is
established based on the requirements of the indirect
water heater.
8. Domestic Hot Water Priority (DHWP)
When domestic hot water priority is selected and
there is a DHW call for heat, the system pump will
be turned off (when “System Pump Run Pump for”
parameter is set for “Central Heat Optional Priority”)
and the DHW pump will be turned on. Additionally, if
outdoor reset is active, the active setpoint is adjusted
to the DHW Setpoint. Priority protection is provided
to ensure central heat supply in the case of excessively
long DHW call for heat.
C. Boiler Protection Features
1. Supply Water Temperature High Limit
The control is equipped with internal operating control
and high limit features. The control monitors a dual
element temperature sensor that is mounted in the
supply water manifold and provides UL353 and UL1998
internal safety algorithms. If supply water temperature
increases above the active setpoint plus diff above,
default 190°F (87.7°C) the boiler is cycled off. If the
temperature exceeds 210°F (98.9°C), a manual reset
hard lockout results. If the boiler is responding to the
internal Multiple Boiler Control Sequencer, Header
Sensor or an External EMS demand and the supply
water temperature increases above 190°F (87.7°C) the
control begins to reduce the blower maximum speed
setting and if the temperature increases to 200°F (93°C)
a forced recycle results. Additionally, if the supply
temperature rises faster than the degrees Fahrenheit
per second limit a soft lockout is activated.
2. High Differential Temperature Limit
The Control monitors the temperature difference
between the return and supply sensors. If this difference
exceeds 52°F (29°C) the control begins to reduce the
maximum blower speed. If temperature difference
exceeds 62°F (34°C) a forced boiler recycle results.
The unit will restart automatically once the temperature
difference has decreased and the minimum off time has
expired. If the temperature difference remains above
72°F (40°C) for longer than 3 minutes a manual reset
hard lockout results.
3. Return Temperature Higher Than Supply
Temperature (Inversion Limit)
The Control monitors the supply and return temperature
sensors. If the return water temperature exceeds the
supply water temperature for longer than a limit time
delay the Control shuts down the boiler and delays
restart. If the inverted temperature is detected more
than five times the boiler manual reset Hard Lockout is
set. This condition is the result of incorrectly attaching
the supply and return piping.
4. External Limit
An external limit control can be installed on the low
voltage terminal strip. Be sure to remove the jumper
when adding an external limit control to the system. If
the external limit opens, the boiler will shut down and
an open limit indication and error code are provided.
If the limit installed is a manual reset type, it will need
to be reset before the boiler will operate.
5. Boiler Mounted Limit Devices
The control monitors individual limit devices: External
Limit, Optional Low Water Cut-Off (LWCO) and
Blocked Flue/Inlet Switch. If any of these limits open
the boiler will shut down and an open limit indication
is provided. Additionally, the control monitors an air
proving switch. During the boiler start sequence the
control requires the air proving switch to be in the
“open” position before the blower starts and in the
“closed” position after the blower starts. If the air
proving switch is not in the required position the start
sequence is halted or the boiler is shut down and the
open limit indication is provided. The air proving
switch is only required to be closed during pre-purge.
It is normal for the air proving switch to be open during
run mode.
6. Stack High Limit
The Control monitors the flue gas temperature sensor
located in the vent connector. If the flue temperature
exceeds 194°F (90°C), the control begins to reduce the
maximum blower speed. If the flue temperature exceeds
204°F (96°C), a forced boiler recycle results. If the
flue temperature exceeds 214°F (101°C), the control
activates a manual reset Hard Lockout.
7. Ignition Failure
The Control monitors ignition using a burner mounted
flame sensor. In the event of an ignition failure, the
control retries 5 times and then goes into soft lockout
for one hour.
8. Central Heating System Frost Protection
When enabled, Frost Protection starts the boiler and
system pump and fires the boiler when low outside air
and low supply water temperatures are sensed. The
Control provides the following control action when
frost protection is enabled:
Summary of Contents for Raptor RPTR085
Page 1: ...1...
Page 13: ...13 Figure 5 1 Wall Layout Mounting Hole Location V Mounting The Boiler continued...
Page 87: ...87 Figure 10 5 Internal Wiring Ladder Diagram X Wiring continued...
Page 88: ...88 X Wiring continued...
Page 97: ...97 Operating Instructions XI Start Up and Checkout continued...
Page 142: ...142 XV Repair Parts continued 3A 3B 3C 3D 3F 3E 3G 3H 3O 3P 3Q 3R 3J 3K 3I 3M 3N 3L All Models...
Page 148: ...148 XV Repair Parts continued 6D 6B 6A 6E 6I 6G 6L 6N 6H 6C 6K 6M 6C 6C 6J 6J 6F All Models...
Page 172: ...172...
