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important that the condensate line is sloped downward away
from the boiler to a suitable inside drain. If the condensate
outlet on the appliance is lower than the drain, you must use
a condensate removal pump, available from Westinghouse
(554200). This pump is equipped with two leads that can be
connected to an alarm or another type of warning device to alert
the user of a condensate overflow, which, if not corrected, could
cause property damage.
3. If a long horizontal run is used, it may be necessary to create
a vent in the horizontal run to prevent a vacuum lock in the
condensate line.
4. Do not expose the condensate to freezing temperatures.
5. It is very important you support the condensation line to
assure proper drainage.
H. Final Checks Before Starting Boiler
1. Read Startup Procedures within this manual for proper steps
to start boiler. (See Startup Report to record steps for future
reference.)
2. Verify the boiler and system are full of water and all system
components are correctly set for operation.
Ensure the boiler is full of water before firing the burner. Failure
to do so will damage the boiler. Such damage IS NOT covered by
warranty, and could result in property damage, severe personal
injury, or death.
3. Fill condensate trap with water.
4. Verify electrical connections are correct and securely attached.
5. Inspect exhaust vent and intake piping for signs of deterioration
from corrosion, physical damage or sagging. Verify exhaust vent
and intake piping are intact and correctly installed per Venting
Section and local codes.
I. Setting Up a Single Boiler
When power is applied to the boiler, the control first completes
a power-up systems check. During this time the combustion fan
may run. The display will initially show the current boiler supply
temperature. If a fault is detected during the power-up test, the
control will display the appropriate fault code. Otherwise, the
display will continue to show the boiler supply temperature and
stand-by, waiting for a demand for heat.
When a demand for heat is received, the control begins the
following demand sequence. The boiler first turns on the pump.
The control will measure the supply temperature. If it is below
the set point temperature minus the ignition differential the
control will ignite the burner.
After the burner is lit, the control modulates the firing rate
to control the supply water temperature and meet the heat
demand. When the
thermostat or indirect water heater
temperature is met, the control will extinguish the burner and
run the combustion fan to purge gasses from the combustion
chamber. In addition, the pump will run for a pump post purge
interval. The control will then be in standby, waiting to process
the next demand for heat.
During this process, the control will extinguish the burner
if it senses a dangerous or unsafe condition. If the control
determines that a dangerous or unsafe condition has occurred,
the control may lock out the boiler and prevent it from igniting
until a maintenance person diagnoses the problem, repairs
it, and resets the control. In the event that the control goes
WHL-033 Rev. 1.29.16
into lockout, it will show a diagnostic code on the display,
illuminate the LED fault indicator, and close the alarm relay
contacts to aid in recognition of the condition, diagnosis, and
repair.
J. Setting Up a Cascaded System
If the boiler is part of a cascaded system the operation is
somewhat different. The control of each boiler in a cascaded
system completes its own power up system check. One of the
boilers in the cascade system is designated as the master boiler.
After the master boiler completes its power up sequence,
it checks the communication bus to see if any other boilers
are present. If other boilers are present, the master control
determines these follower boiler addresses. The master boiler
control will recheck the bus every few seconds as long as it is
powered up to update the status of the connected boilers. The
control in the master boiler processes all heat demands and
dictates which of the follower boilers should light and what
firing rate the followers should try to achieve.
When the master boiler receives a demand for heat, it
determines which boiler is first in the firing sequence and
sends that boiler a command to begin a demand sequence.
That boiler will then begin a demand sequence as described
above. Once the boiler ignites, the master boiler control will
increase the firing rate command to that boiler until the system
sensor temperature is at the set point temperature plus the
differential, or that boiler is at high firing rate. If the command
from the master boiler control gets to the high firing rate of
the follower boiler, but the system sensor is below the required
temperature, the master boiler control will then tell the next
boiler in the firing sequence to begin its demand sequence.
The master boiler control will then begin to ramp up the firing
rate command of that boiler. This process will continue while
there is a demand until all boilers in the cascade system are
at high fire or the desired temperature of the system sensor
is reached. If the system sensor temperature reaches tank
set point and differential before all boilers are at high fire, the
master control will modulate the cascade command signal to
maintain the system sensor at set point and differential until
the demand is complete. When the system sensor is equal
to the set point temperature, demand is complete, and the
master boiler control will extinguish all boilers that may be lit.
If the demand decreases, the firing rate command and amount
of boilers lit will decrease exactly opposite as described above.
Whenever the master boiler control needs to fire a follower
boiler, it sends a firing rate command to that boiler. The follower
boiler will respond to the command until its supply sensor
o
temperature gets to be 5
F above the set point temperature
plus the differential, at which point the individual boiler will
modulate on its own so as not to overheat. As a result, it is
not uncommon to see the cascade output at maximum but
individual boilers firing at less than their maximum firing rate.
K. Lockout Condition
If any boilers, including the master boiler in the cascade
system, are in a lockout condition, the master control will
recognize the lockout condition and skip over the boiler in
the firing sequence. Each boiler in the cascade system is
responsible for its own safety functions. So, if any individual
boiler control senses an unsafe condition, it will extinguish the
burner and, if necessary, go to a lockout condition. In this way,
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