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The hydronic supply and return connections of these
products are for installation in closed loop systems ONLY!
Use of this product in any manner other than described in this
manual may result in premature product failure, substantial
property damage, severe personal injury, or death. Damage or
failure of this product (or the system in which it is installed) due
to unauthorized use IS NOT COVERED BY WARRANTY.
IMPORTANT
In accordance with Section 325 (f) (3) of the Energy Policy
and Conservation Act, Westinghouse has provided this boiler
with multiple features designed to save energy by reducing
the boiler water temperature as heating load decreases.
These features include:
•
A modulating combustion system that adjusts firing
rate based on heat demand.
•
Adjustment of boiler set point based on inferred heat
load as determined by an outdoor sensor. The outdoor
sensor is supplied by Westinghouse with this boiler.
•
This boiler does not include a standing pilot.
•
This boiler is designed and shipped to assure the
highest efficiency operation possible. Such high
efficiency is achieved by limiting heating circuit water
temperature to 140°F when there is no anticipated
heat load, based upon the outdoor sensor and the
Outdoor Reset Curve (sensor response curve) in the
boiler software.
•
This feature may be over-ridden as described below in
specific installations:
•
The boiler control is equipped with an outdoor sensor
override for use with building management systems
or in cascaded systems (for systems with total input of
300,000 BTU/hr or greater).
See statement below for an important notice on the use of
the override.
IMPORTANT
In accordance with Section 325 (f) (3) of the Energy Policy and
Conservation Act, this boiler is equipped with a feature that
saves energy by reducing the boiler water temperature as
the heating load decreases. This feature is equipped with an
override which is provided primarily to permit the use of an
external energy management system that serves the same
function. THIS OVERRIDE MUST NOT BE USED UNLESS AT
LEAST ONE OF THE FOLLOWING CONDITIONS IS TRUE:
•
An external energy management system is installed
that reduces the boiler water temperature as the
heating load decreases.
•
This boiler is not used for space heating.
•
This boiler is part of a modular or multiple boiler
system having a total input of 300,000 BTU/hr or
greater.
•
This boiler is equipped with a tankless coil.
The CSD-1 ASME Code, Section CW-400 requires that hot
water heating and supply boilers have a) a UL 353 temperature
control device, b) at least one (1) temperature-actuated
control to shut off the fuel supply when system water reaches
WHL-016 Rev. 4.14.16
a preset operating temperature, c) a high temperature limit
control that prevents the water temperature from exceeding
the maximum allowable temperature by causing a safety
shutdown and lockout, and d) its own sensing element and
operating switch.
The temperature control system integrated into the 926
control provided with this heating appliance complies with
the requirements of CSD-1 Section CW-400 as a temperature
operation control. The control monitors the temperature
difference between the inlet and the outlet sensor, which is
affected by boiler water flow. If this temperature difference
exceeds 55°F (typically because of low water flow or very low
heat load), the control will reduce the maximum fan speed.
If the temperature difference exceeds 60°F, the control
will effectively sense there is little or no water flow or heat
load and shut the boiler down. The controller will restart
automatically once the temperature difference has dropped
below 55°F and the minimum off time (anti-cycle time) has
expired. In addition, if the control senses that the outlet water
temperature has reached 210°F, the boiler is put into a hard
lockout and requires manual reset to restart.
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