Instructions / Assembly
Table Of Contents
- Part 1 - General Safety Information
 - Part 2 - Before You Start
 - Part 3 - Prepare the Boiler
- A. Locating the Boiler
 - B. Structure
 - C. Leveling
 - D. Clearances for Service Access
 - E. Wall Mounting Considerations
 - F. Wall Mounting Instructions
 - G. Residential Garage and Closet Installations
 - H. Exhaust Vent and Intake Pipe
 - I. Carbon Monoxide Detectors
 - J. Prevent Combustion Air Contamination
 - K. Removing a Boiler from a Common Vent System
 - K. Water Chemistry Requirements*
 - L. Technical Specifications
 
 - Part 4 - Piping
- A. General Plumbing Information
 - B. Relief Valve
 - C. Backflow Preventer
 - D. Potable Expansion Tank
 - E. Circulators
 - F. Hydronic Piping with Circulators, Zone Valves, and Multiple Boilers
 - G. Circulator Sizing
 - H. Check / Control Water Chemistry
 - I. Plumbing
 - J. Fill and Purge Heating System
 - K. Glycol Antifreeze Solutions
 - L. Zoning with Zone Valves
 - M. Zoning with Circulators
 - N. Multiple Boilers
 - O. Applications*
 
 - Part 5 - Venting
 - Part 6 - Condensate Removal
 - Part 7 - Wiring
- A. Installation Must Comply With
 - B. Field Wiring Terminations
 - C. Field Wiring
 - D. Line Voltage Wiring for Standard Boiler
 - E. Alarm Connections
 - F. Low Voltage Connections for Standard Boiler
 - G. Thermostat
 - H. Outdoor Sensor
 - I. Indirect Sensor
 - J. Optional 0-10 Volt Building Control Signal
 - K. Optional UL353 Low Water Cut-Off Interface Kit
 - L. Wiring of Cascade System Communication Bus
 - M. Cascade Master Pump and Sensor Wiring
 - N. Cascade Follower Pump and Sensor Wiring
 
 - Part 8 - Gas Connections
 - Part 9 - Start-Up Preparation
- A. Check / Control Water Chemistry
 - B. Check for Gas Leaks
 - C. Freeze Protection (When Used)
 - D. Fill and Test Water System
 - E. Purge Air from Water System
 - F. Check Thermostat Circuit(s)
 - G. Condensate Removal
 - H. Final Checks Before Starting Boiler
 - I. Setting Up a Single Boiler
 - J. Setting Up a Cascaded System
 - K. Lockout Condition
 - L. Cascade System Programming
 
 - Part 10 - Start-Up Procedure
 - Part 11 - Start-Up Procedures for the Installer
 - Part 12 - Troubleshooting
 - Part 13 - Maintenance
 - Part 14 - Shutdown
 - Part 15 - Installation Checklist
 - Part 16 - Maintenance Report
 - Part 17 - Replacement Parts
 

LP-387 Rev. 011 Rel. 006 Date 6.28.19
3
The following dened terms are used throughout this manual to 
bring attention to the presence of hazards of various risk levels or 
to important product information.
DANGER  indicates an imminently hazardous situation which, if 
not avoided, will result in serious personal injury or death.
WARNING indicates a potentially hazardous situation which, if 
not avoided, could result in personal injury or death.
CAUTION indicates a potentially hazardous situation which, if not 
avoided, may result in moderate or minor personal injury.
CAUTION used without the safety alert symbol indicates a 
potentially hazardous situation which, if not avoided, may result 
in property damage.
NOTICE is used to address practices not related to personal injury.
Foreword
This manual is intended to be used in conjunction with other 
literature provided with the boiler. This includes all related control 
information. It is important that this manual, all other documents 
included in this system, and additional publications including the 
National Fuel Gas Code - ANSI Z223.1 (latest versions), be reviewed in 
their entirety before beginning any work.
Installation should be made in accordance with the regulations of 
the Authority Having Jurisdiction, local code authorities, and utility 
companies which pertain to this type of water heating equipment.
For the Installer
This boiler must be installed by qualied and licensed personnel. 
The installer should be guided by the instructions furnished with the 
boiler, and by local codes and utility company requirements. In the 
absence of local codes, preference should be given to the National Fuel 
Gas Code - ANSI Z223.1, latest version.
Installations Must Comply With:
Local, state, provincial, and national codes, laws, regulations, and 
ordinances.
The latest version of the National Fuel Gas Code, ANSI Z223.1, from 
American Gas Association Laboratories, 8501 East Pleasant Valley 
Road, Cleveland, OH 44131.
In Canada - CGA No. B149 (latest version), from Canadian Gas 
Association Laboratories, 55 Scarsdale Road, Don Mills, Ontario, 
Canada M3B 2R3. Also, Canadian Electrical Code, C 22.1, from Canadian 
Standards Association, 5060 Spectrum Way, Suite 100, Mississauga, 
Ontario, Canada L4W 5N6.
The latest version of the National Electrical Code, NFPA No. 70.
NOTE: The gas manifold and controls met safe lighting and other 
performance criteria when undergoing tests specied in ANSI Z21.13 
- latest edition.
Authority Having Jurisdiction (AHJ) – The AHJ may be a federal, state, 
local government, or individual such as a re chief, re marshal, chief 
of a re prevention bureau, labor department or health department, 
building ocial or electrical inspector, or others having statutory 
authority. In some circumstances, the property owner or his/her agent 
assumes the role, and at government installations, the commanding 
ocer or departmental ocial may be the AHJ.
NOTE: HTP reserves the right to modify product technical specications 
and components without prior notice.










