Service Manual

3Troubleshooting

Table 3F (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface

FAULT

 

DESCRIPTION

 

CORRECTIVE ACTION

 

 

 

 

 

The unit was running and lost the flame

• Inspect spark electrode and associated wiring for

 

signal.

This condition occurred four (4)

damage and connection.

Reference page 26 of this

 

straight times on the 399 model or twice on

manual for removal and cleaning procedures. Replace

 

the 500 - 800 models .

if necessary.

 

 

 

 

 

 

 

 

• Check for proper electrical grounding of unit.

 

 

 

 

• Check incoming supply gas pressure. Natural gas

 

 

 

pressures should be between 4 -

14 inches

w.c.

 

 

 

(1.0 - 3.5 kPa) and LP gas pressures should be

 

 

 

between 8 - 14 inches w.c. (2.0 -

3.2

kPa).

 

 

 

Refer to Section 7 - Gas Connections of the Knight

 

 

 

XL Installation and Operation Manual for detailed

 

 

 

information concerning the gas supply.

 

 

 

 

 

• Verify that the plastic hose from the gas valve to the air

 

 

 

inlet is connected and is not damaged.

 

 

 

 

 

• Verify that the vent/air intake pipes are installed

 

 

 

correctly and there are no obstructions.

 

 

No Flame

 

 

• Check for 24 VAC to the gas valve at the 2-pin

 

 

connection on the side of the main control board during

Running

 

 

the ignition attempt. If no voltage is present, replace the

(will require a manual

 

 

main control board.

 

 

 

 

reset once the condition

 

 

• If 24 VAC is present at the main control board, check

has been corrected.

 

 

Press the RESET button

 

 

the wiring between the main control board and the gas

on the SMART

 

 

valve.

Replace

the wiring if

necessary.

Do not

SYSTEM display to

 

 

disconnect the wiring from the gas valve and attempt to

 

 

measure voltage at that point. The main control board

reset.)

 

 

 

 

can detect if the gas valve is not connected and will

 

 

 

 

 

 

display the Gas Valve Fail fault.

 

 

 

 

 

 

• If 24 VAC is present, check the outlet of the valve to

 

 

 

ensure the valve is flowing gas. With a manometer

 

 

 

connected to the outlet tap of the gas valve, when the

 

 

 

unit is in the prepurge period, there should be a

 

 

 

negative pressure present. When the valve is

 

 

 

energized a change in pressure should occur. If the

 

 

 

pressure change does not occur, the gas valve is not

 

 

 

opening. Replace the gas valve.

 

 

 

 

 

 

• Inspect

flame

sensor

and

associated

wiring.

 

 

 

Reference page 26 of this manual for removal and

 

 

 

cleaning procedures. Replace if necessary.

 

 

 

 

 

• Inspect the burner. Reference page 26 of this manual

 

 

 

for removal and cleaning procedures. Replace if

 

 

 

necessary.

 

 

 

 

 

 

 

 

• Replace the main control board.

 

 

 

 

 

 

 

 

 

 

 

 

 

34

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Image 34
Lochinvar 399 - 800 service manual No Flame, Running

399 - 800 specifications

Lochinvar is known for its cutting-edge water heating and boiler systems, and the Lochinvar 399 - 800 series is no exception. Specifically designed for commercial applications, this series brings advanced technology and engineering to the forefront of hydronic heating solutions.

One of the standout features of the Lochinvar 399 - 800 series is its impressive efficiency. Equipped with a condensing design, these boilers utilize high-efficiency stainless steel heat exchangers that allow for maximum heat transfer while minimizing energy consumption. With an impressive thermal efficiency of up to 96%, the Lochinvar 399 - 800 series stands out in its class, offering significant energy savings and reduced operational costs over time.

Another key characteristic of this series is its robust construction. Designed with longevity in mind, the boilers are built using high-quality materials that withstand extreme temperatures and pressures. The stainless steel design not only enhances durability but also combats corrosion, ensuring a long service life and reduced maintenance costs for users.

The Lochinvar 399 - 800 series also incorporates advanced control technologies. With its intuitive control system, users can easily adjust and monitor heating parameters, ensuring optimal performance and comfort. The integrated Control Wizard feature simplifies the setup process, allowing for quick commissioning and troubleshooting. Additionally, the optional Lochinvar SMART CONTROL technology provides remote monitoring capabilities, allowing operators to keep track of system performance from anywhere.

Versatility is another hallmark of the Lochinvar 399 - 800 series. These boilers come in a range of sizes, with the ability to modulate output based on real-time heating demands. This flexibility ensures that systems can operate efficiently under varying load conditions, making them ideal for schools, hospitals, and commercial buildings requiring consistent hot water availability.

In summary, the Lochinvar 399 - 800 series exemplifies modern boiler technology, combining energy efficiency, durability, advanced controls, and versatility. As businesses and facilities seek to enhance their heating systems, the Lochinvar 399 - 800 offers a reliable and forward-thinking solution for today's energy-conscious environment. Investing in this state-of-the-art boiler system not only improves comfort but also fosters sustainability and cost-effectiveness in commercial heating applications.