Instructions / Assembly

LP-387 Rev. 011 Rel. 006 Date 6.28.19
4
Table of Contents
Part 1 - General Safety Information 5
A. Improper Combustion 6
B. Gas 6
C. When Servicing the Boiler 6
D. Boiler Water 6
E. Freeze Protection 6
F. High Elevation Installations 6
Part 2 - Before You Start 6
A. What’s in the Box 6
B. How the Boiler Operates 6
C. Optional Equipment 7
Part 3 - Prepare the Boiler 7
A. Locating the Boiler 8
B. Structure 8
C. Leveling 8
D. Clearances for Service Access 9
E. Wall Mounting Considerations 9
F. Wall Mounting Instructions 9
1. Mounting to a Wood Studded Wall 10
2. Mounting to a Metal Frame 10
G. Residential Garage and Closet Installations 10
H. Exhaust Vent and Intake Pipe 10
1. Direct Vent of Exhaust and Intake 11
2. Power Venting, Indoor Combustion Air in Conned or Unconned
Space 11
I. Carbon Monoxide Detectors 11
J. Prevent Combustion Air Contamination 11
K. Removing a Boiler from a Common Vent System 12
K. Water Chemistry Requirements* 12
L. Technical Specications 14
Part 4 - Piping 16
A. General Plumbing Information 16
B. Relief Valve 16
C. Backow Preventer 16
D. Potable Expansion Tank 17
E. Circulators 17
F. Hydronic Piping with Circulators, Zone Valves, and Multiple
Boilers 17
G. Circulator Sizing 17
H. Check / Control Water Chemistry 19
I. Plumbing 19
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, HTP 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 ring 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 HTP with this boiler.
• This boiler does not include a standing pilot.
• This boiler is designed and shipped to assure the highest
eciency operation possible. Such high eciency 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
specic 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
o the fuel supply when system water reaches 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 dierence between
the inlet and the outlet sensor, which is aected by boiler water
ow. If this temperature dierence exceeds 55°F (typically
because of low water ow or very low heat load), the control will
reduce the maximum fan speed. If the temperature dierence
exceeds 60°F, the control will eectively sense there is little or no
water ow or heat load and shut the boiler down. The controller
will restart automatically once the temperature dierence has
dropped below 55°F and the minimum o 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.