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can be made up of lime crystals, marble or phosphate chips
that will neutralize the condensate. This may be done by the
installer or you may purchase a condensate neutralizer from
Westinghouse (7450P-212).
2. The boiler is equipped with a ¾ female socket weld fitting
connection that must be piped to a local drain. It is very
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 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
43
WHL-052 Rev. 4.28.16
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