Lochinvar SNA285-125, SNA500-125, SNR200-100, SNR150-100, SNA400-125 service manual Contents

Contents

PLEASE READ BEFORE PROCEEDING . . . . . . . . . . . 3 Hazard Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

THE SHIELD -- HOW IT WORKS . . . . . . . . . . . . . . . . . 4-6 RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1. DETERMINE WATER HEATER LOCATION

Closet and Alcove Installations . . . . . . . . . . . . . . . . . . . . 8 Provide Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Flooring and Foundation . . . . . . . . . . . . . . . . . . . . . . . . 10 Remove Water Heater from Wood Pallet . . . . . . . . . . . 10 Prevent Combustion Air Contamination . . . . . . . . . . . . 10 Removing Water Heater From Existing Common Vent . 11 Combustion & Ventilation Air Requirements . . . . . . . . . 11

2. GENERAL VENTING

Direct Venting Options . . . . . . . . . . . . . . . . . . . . . . . . . 14 Venting and Combustion Air . . . . . . . . . . . . . . . . . . . . . 15 Requirements for Installation in Canada . . . . . . . . . . . . 15 Air Intake/Vent Connections . . . . . . . . . . . . . . . . . . . . . 16 Vent & Air Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3. SIDEWALL DIRECT VENTING . . . . . . . . . . . . . . . . 18-24

4. VERTICAL DIRECT VENTING . . . . . . . . . . . . . . . . 25-28

5. CONVENTIONAL AND SIDEWALL VENTING . . . . 29

6. SYSTEM PIPING

General Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Scalding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Water Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Piping Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Piping Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . 32-34

7. GAS CONNECTIONS

Connecting Gas Supply Piping . . . . . . . . . . . . . . . . . . . 35

Natural Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Pipe Sizing for Natural Gas . . . . . . . . . . . . . . . . . . . 36

Natural Gas Supply Pressure Requirements . . . . . . 36

Propane Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Pipe Sizing for Propane Gas . . . . . . . . . . . . . . . . . . 36

Propane Supply Pressure Requirements . . . . . . . . 36

Check Inlet Gas Supply . . . . . . . . . . . . . . . . . . . . . . . . . 37

Gas Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Gas Valve Replacement . . . . . . . . . . . . . . . . . . . . . . . . 38

8. FIELD WIRING

Low Voltage Connections . . . . . . . . . . . . . . . . . . . . . . . . 39

Power Cord Connection . . . . . . . . . . . . . . . . . . . . . . . . . 39

Runtime Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Alarm Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

9. CONDENSATE DISPOSAL

Condensate Drain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

10. START-UP

Check for Gas Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Inspect/fill Condensate System . . . . . . . . . . . . . . . . . . . . 43 Final Checks Before Starting the Water Heater . . . . . . . 44-46

11. OPERATING INFORMATION

How the Water Heater Operates . . . . . . . . . . . . . . . . . . . 47

Temperature Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Protection Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Water Heater Temperature Regulation . . . . . . . . . . . . . . 48

Adjustable Control Parameters . . . . . . . . . . . . . . . . . . . . 48

Saving Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 49

The Shield Control Module . . . . . . . . . . . . . . . . . . . . . . . 50

Status Display Screens . . . . . . . . . . . . . . . . . . . . . . . . . . 51-52

12. MAINTENANCE
Maintenance and Annual Startup	53
Address Report Problems	54
Inspect Water Heater Interior	54
Clean Condensate Trap	54
Check All Piping for Leaks	54
Flue Vent System and Air Piping	55
Check Water System	55
Check Expansion Tank	55
Check Water Heater Relief Valve	55
Inspect Ignition & Flame Sense Electrodes	56
Check Ignition Ground Wiring	56
Check All Water Heating Wiring	56
Check Control Settings	56
Perform Startup & Checks	56
Check Burner Flames	56
Check Flame Signal	56
Review with Owner	56
Handling Ceramic Fiber Materials	57
Cleaning Water Heater Heat Exchanger	57
Oiled Bearing Circulators	57
13. TROUBLESHOOTING

Before Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Troubleshooting Chart - No Display . . . . . . . . . . . . . . 59

Checking Temperature Sensors . . . . . . . . . . . . . . . . . 60

Troubleshooting Chart - Noisy System . . . . . . . . . . . 61

Troubleshooting Chart - Fault Messages Displayed . 62-67

Combustion Analysis Procedure . . . . . . . . . . . . . . . . . . . 68

Gas Valve Adjustment Procedure . . . . . . . . . . . . . . . . . . 69

14. DIAGRAMS

Ladder Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

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