Contents | Lochinvar SNA285-125, SNA500-125, SNR200-100, SNR150-100

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

SNA400-125, SNR150-100, SNA285-125, SNR200-100, SNA500-125 specifications

Lochinvar has established itself as a leader in the realm of high-efficiency heating solutions, and its line of condensing boilers, including the SNA500-125, SNR200-100, SNA400-125, SNA285-125, and SNR150-100, exemplifies the brand’s commitment to innovation, efficiency, and reliability.

The SNA500-125 model stands out with its impressive heating capacity, designed for larger commercial applications. Featuring advanced modulating burners, it can precisely adjust its output based on real-time demand, significantly enhancing energy efficiency. The stainless steel heat exchanger ensures robust durability and improved thermal performance, while the integrated controls offer advanced diagnostic capabilities and user-friendly operation.

Next in the lineup, the SNR200-100 serves as a versatile option for mid-sized applications. Its compact design allows for flexible installation, making it a valuable choice for facilities with limited space. The boiler incorporates a high-efficiency combustion system that maximizes fuel utilization, while its low NOx emissions technology aligns with environmental standards, reducing the carbon footprint of users.

The SNA400-125 delivers a robust solution for diverse heating needs, equipped with state-of-the-art modulation technology that not only optimizes efficiency but also offers quiet operation – a crucial feature for facilities where noise reduction is paramount. This model also includes built-in redundancy options, enhancing reliability during peak operational periods.

The SNA285-125 provides a balance of performance and efficiency for smaller commercial settings. Its innovative control system offers precise temperature management and easy integration with existing systems. Energy Star certified, this model is not only cost-effective but supports sustainability efforts in various industries.

Lastly, the SNR150-100 is ideally suited for light commercial applications, featuring a compact footprint and excellent heat transfer capabilities. The user-friendly interface and robust safety features make it an excellent choice for operators prioritizing both ease of use and reliability.

All these models incorporate Lochinvar's commitment to superior design and advanced technologies, setting a benchmark in the high-efficiency heating market. With a focus on long-term performance and compliance with modern environmental standards, Lochinvar continues to deliver top-tier solutions tailored to meet diverse customer needs. Whether for large-scale operations or smaller settings, these boilers represent a significant advancement in commercial heating technology.