Boiler temperature regulation

11 Operating information

Monitor external limits

Connections are provided on the connection board for external limits such as flow switch, low water cutoff, gas pressure switches, and a louver proving switch. The SMART SYSTEM will shut off the burner and inhibit relighting whenever any of these external limits open.

Run-time and alarm outputs

The boiler provides dry contacts for indicating when the boiler is running, and when it is unable to operate.

Run-time and cycle counting

The control uses two timers to monitor the total hours of burner operation. One timer monitors the time the boiler is firing in the Space Heating Mode. The other timer monitors the time the boiler is in the DHW Mode.

The control uses two (2) ignition counters to monitor the amount of boiler cycles. The first counter counts all ignitions of the control. The second counter counts only ignition attempts that have failed.

Service reminder

The control can be programmed for service reminder notification. This notification will become active when either a set time frame has expired, or a set amount of running hours or cycles has expired (all adjustable by the installer). The display will show a Maintenance Required screen. The installer's name and phone number can be programmed into the control. This information will appear on the Maintenance Required screen. The service reminder notification can be reset or disabled by the installer.

Error logging

The control will hold in memory the last 10 lockouts as well as the last 10 blockings. The date and time of the occurrence will be recorded as well. Only the 10 most current occurrences of each will be held in memory.

Operating temperature (target)

The SMART SYSTEM control module senses water temperature and regulates boiler firing and firing rate to achieve a target temperature. The target temperature can be set between 32°F and 190°F.

•Target temperature is fixed when the outdoor sensor is not installed.

•Target temperature is calculated as described in this section under “Outdoor Reset Operation” and “Target Temperature Boost” when the outdoor sensor is connected.

Installation & Operation Manual

High limit operations

The Knight wall mount is equipped with adjustable automatic reset and manual reset high limits. The automatic reset high limit has a maximum set point of 200°F and the manual reset high limit has a maximum set point of 210°F.

When the outlet temperature exceeds 200°F, the automatic high limit action occurs. The boiler shuts down until the outlet water temperature cools below 190°F, and a 60 second timer has expired. If the outlet temperature continues to increase, the manual reset high limit action will occur at 210°F.

High limit test procedure

NOTICE	Please note that the brackets ([]) denote
	screen status.
	screen status.

1.Turn ON the main power to the boiler by placing the ON/OFF switch in the ON position.

2.From the Status Screen, press the NAVIGATION dial to access the Set Points Screen.

3.Press the LEFT SELECT (LIMITS) key.

4.Select the manual reset high limit (MRHL) by rotating the NAVIGATION dial counterclockwise, then press the NAVIGATION dial.

5.Decrease the set point of the MRHL to below the current outlet temperature (or to its minimum setting, whichever is higher) by turning the NAVIGATION dial counterclockwise.

6.Press the RIGHT SELECT [SAVE] key.

7.Press the RIGHT SELECT [HOME] key. The new parameter will upload to the control.

8.If the current outlet temperature is above the new MRHL set point, the MRHL will function causing boiler lockout. If this occurs, skip to Step 11.

9.If the current outlet temperature is below the new MRHL set point, locate the pinhole (SERVICE button) below the RESET button on the display board. Insert a thin probe (such as a paper clip) into the hole and press the button continuously for five (5) seconds to place the boiler into Service Mode. In Service Mode, the boiler will fire at ignition speed and will then modulate up to full fire.

10.Once the outlet temperature rises up to the MRHL set point, the MRHL will function, causing the boiler to shut down and lock out.

11.Repeat Steps 2, 3 and 4.

12.Set the MRHL to the appropriate set point by turning the NAVIGATION dial clockwise.

13.Repeat Steps 6 and 7.

14.Press the RESET button to clear the lockout.

15.If needed, press the RIGHT SELECT [STOP] key to exit Service Mode.

WH 55-399 specifications

The Lochinvar WH 55-399 is a high-efficiency water heater designed for residential and commercial applications, offering a reliable solution for hot water needs. This model represents an advanced approach to water heating, combining cutting-edge technologies and features that ensure optimal performance and energy efficiency.

One of the standout features of the Lochinvar WH 55-399 is its high thermal efficiency, which is a key factor in reducing energy consumption and operating costs. With an efficiency rating exceeding 90%, this water heater ensures that more energy is converted into usable hot water, making it an environmentally friendly choice.

The WH 55-399 utilizes advanced condensing technology, which allows it to extract additional heat from the exhaust gases before they are expelled. This process not only increases efficiency but also significantly decreases greenhouse gas emissions. The unit is also equipped with an intelligent control system that allows for precise temperature adjustments, ensuring that the user has an optimal supply of hot water while maintaining energy savings.

Another important aspect of this model is its impressive recovery rate. The ability to quickly heat water after a significant draw ensures that users will not experience interruptions in their hot water supply, making it ideal for busy households or commercial environments. This is particularly beneficial in applications requiring consistent hot water availability, such as restaurants or athletic facilities.

The Lochinvar WH 55-399 is designed with durability in mind. Constructed from high-quality materials, this water heater boasts a robust tank lined with corrosion-resistant coatings, extending the lifespan of the unit and reducing maintenance needs. Additionally, it features a reliable gas burner and a well-insulated tank, contributing to its overall efficiency and performance.

Safety is also a priority with the WH 55-399. The unit incorporates multiple safety features, including a flame sensor, automatic shut-off valve, and over-temperature protection, ensuring peace of mind for users.

In summary, the Lochinvar WH 55-399 stands out with its combination of high efficiency, advanced technology, and durable construction. Whether for residential or commercial use, this water heater provides a dependable and cost-effective solution for all hot water needs. Its innovative design and performance characteristics make it a top choice for anyone seeking a premium water heating option.