HTP MC120 - Manual (Page 4)

4
LP-171 Rev. 4.10.14
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 specified in ANSI
Z21.10.3
– latest edition.
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.
TABLE OF CONTENTS
PART 1 – GENERAL SAFETY INFORMATION .......................................................................................................................... 6
A. PRECAUTIONS .......................................................................................................................................................................... 6
B. IMPROPER COMBUSTION ........................................................................................................................................................ 7
C. GAS ............................................................................................................................................................................................ 7
D. WHEN SERVICING THE HEATER ............................................................................................................................................. 7
E. HEATER SYSTEM ...................................................................................................................................................................... 7
F. WATER CHEMISTRY* ................................................................................................................................................................ 7
G. WINTERIZING ............................................................................................................................................................................ 8
PART 2 – BEFORE YOU START ................................................................................................................................................ 8
A. WHAT’S IN THE BOX ................................................................................................................................................................. 8
B. HOW THE HEATER OPERATES ............................................................................................................................................... 8
C. OPTIONAL EQUIPMENT ......................................................................................................................................................... 10
PART 3 – PREPARE HEATER LOCATION .............................................................................................................................. 10
A. BEFORE LOCATING THE HEATER ........................................................................................................................................ 10
B. LEVELING ................................................................................................................................................................................ 11
C. CLEARANCES FOR SERVICE ACCESS ................................................................................................................................. 12
D. RESIDENTIAL GARAGE, CLOSET, AND ALCOVE INSTALLATIONS .................................................................................... 12
E. EXHAUST VENT AND INTAKE PIPE ....................................................................................................................................... 13
F. PREVENT COMBUSTION AIR CONTAMINATION .................................................................................................................. 13
G. REMOVING AN EXISTING HEATER FROM AN EXISTING COMMON VENT SYSTEM ........................................................ 13
PART 4 – PREPARE HEATER .................................................................................................................................................. 14
A. REMOVE HEATER FROM BOX ............................................................................................................................................... 14
B. WALL MOUNTING CONSIDERATIONS ................................................................................................................................... 14
C. WALL MOUNTING INSTRUCTIONS ........................................................................................................................................ 14
D. INSTALLATION STEPS ............................................................................................................................................................ 15
PART 5 – HEATER PIPING ....................................................................................................................................................... 15
A. GENERAL PIPING INFORMATION .......................................................................................................................................... 15
B. RELIEF VALVE ......................................................................................................................................................................... 16
C. SEPARATE LOW WATER CUTOFF ........................................................................................................................................ 17
D. BACKFLOW PREVENTER ....................................................................................................................................................... 17
E. SYSTEM WATER PIPING METHODS ..................................................................................................................................... 17