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WARNINGS 4
BEFORE INSTALLATION 5
Product Receipt 5
Model Identification 5
Ratings and Certifications 5
Installations at Elevation 5
Component Locations 6
General Information 6
GENERAL SAFETY 7
Time/Temperature Relationships in
Scalds 7
INSTALLATION 8
Installation Codes 8
Equipment Base 8
Clearances 8
Combustion and Ventilation Air 9
Conventional Combustion Air Supply 11
Water Piping 12
Hydronic Heating 14
Gas Supply 19
Electrical Power Connections 20
Field Wiring Connection 22
Venting 22
Venting Installation Tips 24
Venting Configurations 24
Outdoor Installation 29
Controls 30
Heater Sequence of Operation 36
WIRING DIAGRAMS 41
START-UP 43
Pre Start-up 43
Start-Up 44
OPERATION 47
Lighting Instructions 47
To Turn Off Gas To Appliance 48
TROUBLESHOOTING 49
UDB Fault History 50
MAINTENANCE 50
Suggested Minimum
Maintenance Schedule 50
Preventative Maintenance Schedule 51
APPENDIX 52
Inside Air Contamination 52
CONTENTS
3
Important Instructions for the
Commonwealth of Massachusetts 53
WARRANTY 54
START-UP CHECKLIST 56